section 03500 - unsuitable material

DIVISION 3 - EARTH WORKS Unsuitable Material - Section 03500

SECTION 03500 - UNSUITABLE MATERIAL

TABLE OF CONTENTS

1. DESCRIPTION........................................................................................................................................... 1

2. UNSUITABLE MATERIAL ..................................................................................................................... 1

3. WORK REQUIREMENTS........................................................................................................................ 1

4. MEASUREMENT AND PAYMENT ...................................................................................................... 2

4.1 MEASUREMENT ............................................................................................................................................ 2 4.2 PAYMENT...................................................................................................................................................... 2

Rehabilitation of Kabul-Dushi Highway, Afghanistan 02/04/03 03500 - i


SECTION 03500 - UNSUITABLE MATERIAL

1. DESCRIPTION

This Specification section address excavating, ripping, loading, hauling and spreading in waste areas, of soil material designated by the Engineer as “Unsuitable”

2. UNSUITABLE MATERIAL

(a) Material shall be classified as “Unsuitable” in the following cases:

♦ When the material resulting from the excavation made for the construction of the road or structure is declared in writing by the Engineer to be unsuitable for use in the embankment or other work. Such materials will generally include highly organic clays and silts, peat, soil containing large amounts of roots, grass and other vegetable matter, domestic or industrial waste.

♦ When the material resulting from the excavation made for the construction of the road is surplus to the amount required for the construction of the embankment, provided, however, it is not material rendered surplus by reason of the Contractor having opened borrow pits solely for his own convenience as provided under Specification section 03300.

(b) The material proposed for wasting shall not be wasted until approved or directed in writing by the Engineer.

(c) Materials that are soft or unsuitable merely because they are too wet or dry are not to be classified as unsuitable unless otherwise directed by the Engineer.

3. WORK REQUIREMENTS

(a) Unsuitable material shall be excavated below sub-grade level in cut and below embankment foundation level to the depth shown on the Drawings or directed by the Engineer. Where unsuitable material is excavated below the normal sub-grade level or below embankment foundation or for benching under embankments, the excavation shall be back filled with material and in a manner in conformance with the requirements of Specification section 03400 “Embankment Construction”.

(b) Unsuitable material shall be removed and disposed of in waste areas provided by the Contractor in such manner as to present a neat appearance and not to obstruct drainage to any highway nor to cause injury to highway

Rehabilitation of Kabul-Dushi Highway, Afghanistan 02/04/03 03500 - 1 of 2


works or property. If it becomes necessary for the Contractor to locate or relocate any waste areas, the Engineer prior to spreading any waste shall approve them.

(c) The relevant provisions of Specification section 01700 “Environmental Management” shall be adhered to for the hauling and disposal of unsuitable materials.

(d) Waste areas shall be left in a smooth, neat and drainable condition, as required by the Engineer, and all waste material shall be placed in such manner that adjacent property will not be damaged or endangered. Soil slopes shall not be steeper than 2:1, unless otherwise noted on the drawings or as directed by the Engineer.

4. MEASUREMENT AND PAYMENT

4.1 MEASUREMENT

The quantity of Unsuitable Material to be paid for shall be the number of cubic meters of material acceptably excavated in accordance with Specification requirements and approved by the Engineer, based on field measurements. The material shall be measured in the original position in the natural ground after Site Clearing

4.2 PAYMENT

The work measured as provided above shall be paid for in accordance with applicable Unit Price as indicated on the Bill of Quantities. Payment shall be full for all costs including excavating, ripping, loading, hauling and spreading in waste areas, soil material designated by the Engineer as “Unsuitable”

Pay Item Description

Unit

03500-1 Unsuitable Material m3


DIVISION 3 - EARTH WORKS Granular Backfill - Section 03700

SECTION 03700 - GRANULAR BACKFILL

TABLE OF CONTENTS

1. DESCRIPTION........................................................................................................................................... 1

2. MATERIAL ................................................................................................................................................. 1

3. CONSTRUCTION ..................................................................................................................................... 1

4. MEASUREMENT AND PAYMENT ...................................................................................................... 1

4.1 MEASUREMENT............................................................................................................................................ 1

4.2 PAYMENT ..................................................................................................................................................... 1



SECTION 03700 - GRANULAR BACKFILL

1. DESCRIPTION

This Specification section address supplying and placing and compacting granular back-fill adjacent to structures. The areas in which this material is to be placed shall be as indicated on the drawings or as required by the Engineer.

2. MATERIAL

The material shall be well-graded crushed or uncrushed gravel, stone, rock-fill or natural sand or a well-mixed combination of any of these. Grading requirements for Granular Backfill are as follows:

Maximum size 5 cm

Passing 4.75 mm sieve 25% to 90%

Passing 0.075 mm sieve 0% to 10%

Plasticity Index 6 max.

3. CONSTRUCTION

Granular back-fill shall be placed in uncompacted layers not exceeding 15 cm and compacted to a density of 95% of the maximum dry density determined according to AASHTO T180.


4.1 MEASUREMENT

(a) The quantity of granular back-fill to be measured and paid for will be the number of cubic meters of suitable material supplied and compacted to the Engineer’s satisfaction and in accordance with this Specification section. Materials placed in excess of requirements and dimensions given on the drawings or as required by the Engineer shall not be measured for payment.

(b) Any existing material within areas to receive Granular Backfill, which is removed because of the Contractor’s method of working, shall be replaced by granular back-fill at the Contractor’s expense.

4.2 PAYMENT

The accepted quantities of granular back-fill, measured as provided above shall be paid for in accordance with the applicable Unit Price indicated on the Bill of Quantities. Payment will be full compensation for the work described in this



Specification section, including furnishing, hauling, placing and compacting of material.

Pay Item Description Unit

03700-1 Granular Back-fill m3


DIVISION 3 - EARTH WORKS Aggregate Base - Section 03960

SECTION 03960 - AGGREGATE BASE

TABLE OF CONTENTS

1. DESCRIPTION......................................................................................................................................... 1 2. REFERENCE STANDARDS .................................................................................................................. 1 3. TOLERANCE AND GENERAL REQUIREMENTS .......................................................................... 1 4. SUBMITTALS........................................................................................................................................... 2 5. TRIAL SECTIONS................................................................................................................................... 3 6. RECTIFICATION OF UNSATISFACTORY AGGREGATE BASE................................................ 3 7. EQUIPMENT USED FOR AGGREGATE BASE................................................................................ 4 8. PLACING, SPREADING AND COMPACTING AGGREGATE BASE........................................ 4

8.1 PLACING ...................................................................................................................................................... 4

8.2 SPREADING .................................................................................................................................................. 5

8.3 COMPACTION .............................................................................................................................................. 6

9. CONTROL OF TRAFFIC ON BASE SURFACES .............................................................................. 7 10. TESTING ................................................................................................................................................... 7 11. MATERIALS REQUIREMENTS........................................................................................................... 8

11.1 MATERIAL SOURCES .................................................................................................................................... 8

11.2 STORAGE, MIXING AND HANDLING OF MATERIALS.................................................................................. 8

11.3 UNACCEPTABLE MATERIALS....................................................................................................................... 9

11.4 AGGREGATE BASE MATERIAL REQUIREMENTS .......................................................................................... 9

12. MEASUREMENT AND PAYMENT................................................................................................... 10

12.1 MEASUREMENT.......................................................................................................................................... 10

12.2 MEASUREMENT OF RECTIFIED WORK ....................................................................................................... 11

12.3 PAYMENT ................................................................................................................................................... 11



SECTION 03960 - AGGREGATE BASE

1. DESCRIPTION

This work shall consist of supplying, processing, hauling, spreading, watering and compacting graded aggregate on a prepared and accepted surface, (and in patches, including trimming and preparation of the hole), in accordance with details shown on the Drawings or as directed by the Engineer. Processing shall include, where necessary, crushing, screening, separation, blending, and any other operation necessary to produce a material conforming to the requirements of this Specification section.

2. REFERENCE STANDARDS

The most recent printing of the following AASHTO tests shall apply to the materials covered in this Section:

♦ T 89 - Determining the Liquid Limit of Soils

♦ T 90 - Determining the Plastic Limit and Plasticity Index of Soils

♦ T 96 - Resistance to Abrasion of Small Size Coarse Aggregate by use of the Los Angeles Machine

♦ T 112 - Clay Lumps and Friable Particles in Aggregate

♦ T 180 - Moisture Density Relations of Soils using a 4.54 kg Rammer and a 457 mm Drop

♦ T 191- Density of Soil In-Place by the Sand Cone Method

♦ T 193 -The California Bearing Ratio

♦ T104 - Soundness of Aggregate by use of Sodium or Magnesium Sulfate

3. TOLERANCE AND GENERAL REQUIREMENTS

(a) Tolerances

Aggregate base shall be spread with equipment that will provide a uniform layer which when compacted will conform to the designed thickness, level, longitudinal grade and cross fall or camber as shown on the Drawings. The allowable tolerance shall be as contained in Table 1.



TABLE 1

Tolerances for Aggregate Base

Characteristic Permitted Variation from Drawings

Base

THICKNESS OF LAYER

LEVEL OF SURFACE

LONGITUDINAL GRADE

Measured over 25 m length

CROSS FALL or CAMBER

SURFACE IRREGULARITY

Measured by 3-m straight-edge

+ 10 mm

-10mm to +0mm

+ 0.1 %

+ 0.2%

5mm

(b) The surface of all construction Aggregate Base layers shall not have any irregularities which can hold moisture and the camber of all such surfaces shall comply with that shown on the Drawings.

(c) When testing the irregularity of Aggregate Base surfaces to be treated with bituminous surfacing, all loose material shall be removed by hard brooming.

4. SUBMITTALS

The Contractor shall submit the following to the Engineer at least 21 days prior to the proposed date of first using any material proposed for use as Aggregate Base:

(a) One sample of 50 kg weight for every 500m3 of the material, one of which shall be retained by the Engineer for reference throughout the Contract Period;

(b) a statement of the origin and composition of any material proposed for use as Aggregate Base, together with laboratory test data for every 500m3 verifying that the material properties specified in this Section are met.

The Contractor shall submit the following in written form to the Engineer immediately following completion of each section of the work and before any



approval may be granted for the placing of other materials on top of the Aggregate Base:

(a) the results of testing as specified in Subsection 10(a) and 10(f) if this Specification Section.

(b) the results of surface measurement tests and survey data verifying that the surface and thickness tolerances shown on Table 1 are met.

5. TRIAL SECTIONS

(a) Before either subbase or base construction is started, the Contractor shall spread and compact trial sections as directed by the Engineer. The purpose of the trial section is to check the suitability of the materials and the efficiency of the equipment and construction method which is proposed to be used by the Contractor. Therefore, the Contractor must use the same materials, equipment and procedures that he proposes to use for the main work. One trial section about 500 m2 shall be made for every type of material and/or construction equipment/procedure proposed for use.

(b) Density tests and other tests required as directed by the Engineer.

(c) If in the Engineer’s opinion the materials are not suitable for base as appropriate to the trial, they shall be removed at the Contractor’s expense, and a new trial section shall be constructed.

(d) If the basic conditions regarding the type of material or procedure change during the execution of the work, new trial sections shall be constructed.

6. RECTIFICATION OF UNSATISFACTORY AGGREGATE BASE

(a) Areas with a thickness or surface uniformity not satisfying the tolerances specified in, or which develop irregularities in the surface during or after construction, shall be rectified by loosening the surface and removing or adding material as required, followed by reshaping and recompacting.

(b) Aggregate Base which is too dry for compaction, in terms of the moisture content limits as specified in or as directed by the Engineer, shall be corrected by scarifying the material followed by sprinkling with an adequate quantity of water and thoroughly mixing by means of equipment approved by the Engineer.

(c) Aggregate Base which is too wet for compaction, as defined by the moisture content limits specified in or as directed by the Engineer, shall be rectified by scarifying the material followed by intermittent working by motor grader or other approved equipment to air-dry the material under dry weather conditions. Alternatively, or if sufficient drying cannot be achieved by re-



working the loose material, the Engineer may direct that the material be removed from the work and replaced with suitably dry material.

(d) Aggregate Base which becomes saturated from rain or flooding or otherwise after it has already been satisfactorily compacted according to this Specification section will generally require no rectification work provided its material properties and surface uniformity meet the requirements of this Specification section.

(e) Rectification of Aggregate Base which does not meet the density or material property requirements of this Specification section shall be as directed by the Engineer and may include additional compaction, loosening followed by moisture content adjustment and recompaction, removal and replacement of the material, or the use of an additional thickness of material.

7. EQUIPMENT USED FOR AGGREGATE BASE

(a) Equipment and method used shall place the Aggregate Base to the line, levels, grades, dimensions and cross-section shown in the Drawings and as directed by the Engineer.

(b) The Engineer has the right to stop the use of any equipment or plant which he deems to be inferior to the quality required and to instruct the removal of such equipment and to have it replaced by suitable equipment or to alter the method of operation at any time.

(c) The Contractor shall immediately comply with such instructions without being entitled to any indemnities or extensions as a result of such instructions. The Contractor shall not be allowed to use any equipment or plant before obtaining the approval of the Engineer, and the Contractor shall undertake to follow sound technical methods in operation and to engage skilled and trained operators, mechanics and labor to carry out the Works. The Engineer has the right to expel any operators, mechanics or labor and to instruct suitable replacement thereof at any time he deems such action is necessary.

8. PLACING, SPREADING AND COMPACTING AGGREGATE BASE

Aggregate Base shall not be placed, spread or compacted while rain is falling, and no compaction shall be carried out when moisture content of the material falls outside the specified range.

8.1 PLACING

(a) The aggregate base material shall be placed in accordance with Drawing requirements as a uniform mixture in a quantity which will provide the required compacted thickness. In locations where base materials are to be



placed on a prepared subgrade, the subgrade shall be prepared in accordance with Specification section 03210 “Subgrade Preparation” prior to base and/or subbase placement.

(b) When more than one layer is required, each layer shall be compacted as specified in Sub-Section 8.3(e) of this Specification section, before the succeeding layer is placed.

(c) The placing of material shall begin at the point designated by the Engineer.

(d) The area being prepared for laying the base material shall be completed and the approval of the Engineer obtained for at least 200m ahead of the placing of the subbase and base at all times.

(e) Hauling equipment may be routed over completed portions of the base courses provided no damage results and provided that such equipment is routed over the full width of the course to avoid rutting or uneven compaction. The Engineer has the right to stop all hauling over completed or partially completed base courses when in his opinion such hauling is causing damage.

8.2 SPREADING

(a) Where the required thickness is 150mm or less, the material may be spread and compacted in one layer. Where the required thickness is more than 150mm, the aggregate base shall be spread and compacted into two or more layers of approximately equal thickness, and the maximum compacted thickness of any one layer shall not exceed 150mm unless otherwise directed by the Engineer. All subsequent layers shall be spread and compacted in a similar manner.

(b) Aggregate Base shall be delivered to the roadbed as a uniform mix and shall be spread at a moisture content within the range specified in this Specification section. The moisture shall be uniformly distributed throughout the material.

(c) Aggregate Base shall be spread and shaped by self-propelled pavers only, which do not cause segregation of the fine and coarse aggregate particles. Segregated material shall be corrected or removed and replaced with graded material.

(d) Immediately following final spreading and smoothening, each layer shall be compacted to the full width by means of approved compaction equipment. Rolling operations shall begin along the edges and progress gradually towards the center, in a longitudinal direction. On super-elevated sections rolling shall begin at the low side and progress towards the high side. The



rolling operation shall continue until all roller marks are eliminated and the layer is uniformly compacted and the aggregates firmly keyed. Any irregularities or depressions that develop shall be corrected by loosening the material at these places and adding or removing material until the surface is smooth and uniform. Along curbs, headers, and walls, and at all places not accessible to the roller, the subbase and base material shall be compacted thoroughly with approved tampers or compactors. At the end at each shift, the surface of the base and subbase shall be shaped and sloped to prevent ponding of rain water.

Aggregate Base surfaces which are to receive a prime coat shall then be further compacted to produce a stable, tightly locked surface, without open pores, suitable for priming. All coarse aggregate shall be tightly locked in place. Under no circumstances shall any form of soil or fine aggregate be added to the surface to assist the locking process, which shall be achieved by compaction only. Vibration shall not be used in the final stages of the compaction of the surface. The Engineer may direct that pneumatic rollers be used for the final surface compaction, if static steel wheeled rollers are considered likely to cause excessive breakdown or degradation of the aggregate base.

8.3 COMPACTION

(a) Compaction shall be carried out only when the moisture content of the material is within the range of 3% less than optimum moisture content to 2% more than optimum moisture content, where the optimum moisture content is as defined by the maximum modified dry density determined by AASHTO T 180, Method D.

(b) When the underlying material is soft or yielding the base course, compaction shall be stopped and the underlying materials rectified as directed by the Engineer.

(c) During all the operations of spreading, compacting and leveling of subbase and base course material, care must be taken so that layers already compacted under the layer being executed are not affected, or that the finished subgrade or base surface is also not affected. Special attention must be given in places where equipment makes turns in going back and forth. Any such damage resulting in mixing the various layers constituting the different subgrades and base courses shall be carefully made good by the Contractor and at his expense and to the satisfaction of the Engineer.

(d) If the layer of base material, or part thereof, does not conform to the required finish, the Contractor shall, at his own expense, make the necessary corrections.



(e) Compaction of each layer shall continue until a field density of at least 100 percent of the maximum dry density determined in accordance with AASHTO T180, Method D, has been achieved. In place density determination shall be made in accordance with AASHTO T 191.

9. CONTROL OF TRAFFIC ON BASE SURFACES

(a) Construction or other traffic shall not be permitted to travel on any aggregate layers, prior to the construction of the final surfacing, except where directed or permitted by the Engineer.

(b) The aggregate base shall not be opened to traffic until shaping and compaction is substantially complete.

(c) Pending the construction of the final surfacing, the Aggregate Base shall be maintained as follows:

♦ The aggregate base shall be maintained at all times by drag brooming. The traffic shall be controlled by temporary speed restrictions and, during working hours, it shall be channeled by suitably defined traffic lanes, with frequent transverse shift of the defined lanes to obtain an even spread of traffic over the entire surface.

♦ Where the pavement course is too dry, so that surface stability does not or is unlikely to improve under the effect of traffic and/or rolling and where rain is not imminent or has been insufficient, a uniform application of water shall be applied to the entire surface. Up to 4 liters/square meter shall be applied in gradual increments so as to avoid flooding or scouring the surface.

10. TESTING

(a) The amount of supporting test data required for initial approval of the quality of the material will be as directed by the Engineer, but will include all the tests specified in this Section on at least three representative samples from the proposed material source, selected to represent the range of material quality likely to be obtained from the source.

(b) Following approval of the quality of a proposed material, the full range of material quality tests performed will be repeated subsequently, at the discretion of the Engineer, in the event of observed changes in the material or in its source or in its method of production.

(c) A program of routine material quality control testing will be carried out to control variability of the material being brought on site. The extent of the testing shall be directed by the Engineer, but for every 3000 cubic metres of



material produced the testing shall include no less than five (5) plasticity index tests, five (5) particle grading tests, and one (1) maximum dry density determination using AASHTO T 180, Method D. CBR tests shall be carried out from time to time as directed by the Engineer.

(d) The density and moisture content of the compacted material shall be routinely determined, using AASHTO T 191. The test shall be made to the full depth of the layer at locations as directed by the Engineer, but not more than 200 m apart.

(e) All holes in the finished work made by density testing or otherwise shall be backfilled with the specified material by the Contractor without delay and compacted to the density and surface tolerance requirements of this Specification section.

11. MATERIALS REQUIREMENTS

11.1 MATERIAL SOURCES

All materials shall be tested and approved by the Engineer before use. The Contractor shall notify the Engineer of the sources of materials and the Engineer will approve the sources prior to delivery of materials to the Site. Where the source of material does not meet Specification requirements, the Contractor shall furnish material from other sources. Delivery of materials produced from commercial manufacturing processes shall be accompanied by the manufacturer’s certification and test report showing the materials comply with the Specification requirements. The Engineer’s approval of a source does not imply that all the material in that source is approved.

11.2 STORAGE, MIXING AND HANDLING OF MATERIALS

(a) Materials shall be so stored and handled as to assure the preservation of their quality and fitness for construction. Materials, even though approved before storage or handling, may again be inspected and tested prior to use. Stored material shall be located to facilitate prompt inspection.

(b) Handling and stockpiling of aggregates shall be to the approval of the Engineer and at all times be such as to eliminate segregation of the various sizes and contamination.

(c) Aggregate stockpiles for base course shall be protected from rain to prevent saturation of the aggregates which would result in a reduction in the quality of the placed material or adversely affect the placement of the material

(d) Where separate size materials are to be blended to meet the gradation, such blending shall be as directed by the Engineer and shall be accomplished



prior to delivery to the roadway. Mixing of separate materials on the roadway by motor grader will not be permitted by the Engineer.

11.3 UNACCEPTABLE MATERIALS

Materials that do not comply with the requirements of this Specification section shall be rejected and removed immediately from the site of the Works unless otherwise instructed by the Engineer. No rejected materials, the defects of which have been corrected, shall be used until approval has been given by the Engineer.

11.4 AGGREGATE BASE MATERIAL REQUIREMENTS

Aggregate Base shall consist of hard, durable particles of fragments of stone or gravel crushed to the size and of the quality requirements of this Specification section. Aggregate Base shall be cleaned and free from vegetable matters, lumps or balls of clay and other deleterious substances. The material shall be of such nature that it can be compacted readily to form a firm, stable base. Aggregate Base shall conform, using wet sieve testing, to the properties given in Table 2.

TABLE 2

Aggregate Base Properties

Properties Base

Abrasion of Aggregate retained on 2.00 mm (No.10) sieve (AASHTO T 96)

35% max.

Plasticity Index of Aggregate passing the 0.425 mm (No. 40) sieve (AASHTO T 90)

Non-plastic.

Percent by weight of Aggregate retained on 2mm (No.10) sieve with one fractured face

90% min.

Liquid Limit of Aggregate passing the 0.425 (No. 40) sieve (AASHTO T 89)

Non-plastic

Soaked CBR (AASHTO T 193) at maximum dry density according to AASHTO T 180 Method D

for material passing 19 mm sieve 80% min.

The base material shall conform to the grading requirements of Table 3.

TABLE 3

Grading Requirements for Aggregate Base

Sieve Designation

Standard (mm) Alternative US Standard Mass Percent Passing



37.5 1 ½ inch 100

25 1 inch 80 – 100

19 ¾ inch 50-85

4.75 No. 4 25-45

0.425 No. 40 8-22

0.075 No. 200 2-9

The portion of the material passing the 0.075 mm (No. 200) sieve shall not be greater than 0.66 (two thirds) of the fraction passing the 0.425 (No. 40) sieve.

(e) If filler, in addition to that naturally present, is necessary for meeting the grading requirements or for satisfactory bonding, it shall be uniformly blended with the crushed base course material as approved by the Engineer. Filler shall be obtained from sources approved by the Engineer, free from hard lumps and shall not contain more than 15 percent of material retained on the 4.75 mm (No.4) sieve according to AASHTO T 112.

Aggregate base shall conform, using wet sieve testing, to the properties given in Tables 2 and 3.


12.1 MEASUREMENT

(a) Aggregate Base shall be measured as the number of cubic meters of compacted material required, complete in place and accepted. The volumes to be measured shall be based on the cross sections shown on the drawings and approved by the Engineer and lengths measured horizontally along the road centerline. No allowance will be given for materials placed outside the design limits shown on the cross-sections. Trial sections shall not be measured separately but shall be included in the quantity of subbase and base measured.

(b) The work of preparing and maintaining the subbase on which the aggregate base is to be placed shall be addressed in accordance with requirements and stipulations of Specification section 03400 “Subgrade Preparation”.

(c) No separate measurement for payment will be made for any Running Course gravel used for temporary protection of the surface of Aggregate Base exposed to traffic.

(d) No additional measurement for payment will be made for repairs to layers caused by traffic or natural conditions.

(e) No additional measurement for payment will be made for extra material provided in the next course for a deficiency in the subbase or base course.



12.2 MEASUREMENT OF RECTIFIED WORK

(a) Where rectification of unsatisfactory base has been directed by the Engineer, the quantities to be measured for payment shall be those, which would have, been paid if the original work had been acceptable. No additional payment will be made for the extra work or quantities necessitated by the rectification.

(b) Where adjustment of moisture content has been directed by the Engineer prior to compaction, no additional payments will be made for adding water or drying out the material or for any other work required to obtain a satisfactory moisture content.

12.3 PAYMENT

The quantities determined, as provided above, shall be paid for in accordance with Unit Prices as indicated on the Bill of Quantities for each of the particular Pay Items. Payment shall be full compensation for hauling, supplying, placing, compacting, finishing and testing the materials, the supply and placing of running course and maintenance of the surface under traffic, and all other costs necessary or usual to the proper completion of the work prescribed in this Specification section.


Unit

R-03960-1 Aggregate Sub Base m3

R-03960-2 Aggregate Base m3


DIVISION 3 - EARTH WORKS Granular Subbase - Section 03965

SECTION 03965 - GRANULAR SUBBASE AND SHOULDER

TABLE OF CONTENTS

1. DESCRIPTION......................................................................................................................................... 1 2. REFERENCE STANDARDS .................................................................................................................. 1 3. TOLERANCE AND GENERAL REQUIREMENTS .......................................................................... 1 4. SUBMITTALS........................................................................................................................................... 2 5. RECTIFICATION OF UNSATISFACTORY GRANULAR SUBBASE .......................................... 3 6. EQUIPMENT USED FOR GRANULAR SUBBASE .......................................................................... 4 7. PLACING, SPREADING AND COMPACTING GRANULAR SUBBASE .................................. 4

7.1 PLACING ...................................................................................................................................................... 4

7.2 SPREADING .................................................................................................................................................. 5

7.3 COMPACTION .............................................................................................................................................. 6

8. CONTROL OF TRAFFIC ON GRANULAR SUBBASE SURFACES ............................................. 6 9. TESTING ................................................................................................................................................... 7 10. MATERIALS REQUIREMENTS........................................................................................................... 7

10.1 MATERIAL SOURCES .................................................................................................................................... 7

10.2 STORAGE, MIXING AND HANDLING OF MATERIALS.................................................................................. 8

10.3 UNACCEPTABLE MATERIALS....................................................................................................................... 8

10.4 GRANULAR SUBBASE MATERIAL REQUIREMENTS...................................................................................... 8

11. MEASUREMENT AND PAYMENT..................................................................................................... 9

11.1 MEASUREMENT............................................................................................................................................ 9

11.2 MEASUREMENT OF RECTIFIED WORK ....................................................................................................... 10

11.3 PAYMENT ................................................................................................................................................... 10



SECTION 03965 – GRANULAR SUBBASE AND SHOULDER

1. DESCRIPTION

This work shall consist of supplying, processing, hauling, spreading, watering and compacting granular subbase and shoulder material on a prepared and accepted surface (and in patches, including trimming and preparation of the hole), in accordance with details shown on the Drawings or as directed by the Engineer. Processing shall include, where necessary, crushing, screening, separation, blending, and any other operation necessary to produce a material conforming to the requirements of this Specification section. All references in this Specification to subbase also apply to shoulder material


The most recent printing of the following AASHTO tests shall apply to the materials covered in this Section:

♦ T 89 - Determining the Liquid Limit of Soils

♦ T 90 - Determining the Plastic Limit and Plasticity Index of Soils

♦ T 96 - Resistance to Abrasion of Small Size Coarse Aggregate by use of the Los Angeles Machine

♦ T 112 - Clay Lumps and Friable Particles in Aggregate

♦ T 180 - Moisture Density Relations of Soils using a 4.54 kg Rammer and a 457 mm Drop

♦ T 191- Density of Soil In-Place by the Sand Cone Method

♦ T 193 -The California Bearing Ratio

♦ T104 - Soundness of Aggregate by use of Sodium or Magnesium Sulfate

3. TOLERANCE AND GENERAL REQUIREMENTS

(a) Tolerances

Granular subbase shall be spread with equipment that will provide a uniform layer which when compacted will conform to the designed thickness, level, longitudinal grade and cross fall or camber as shown on the Drawings. The allowable tolerance shall be as contained in Table 1.



Table 1

Tolerances for Granular Subbase

Characteristic Permitted Variation from Drawings

THICKNESS OF LAYER

LEVEL OF SURFACE

LONGITUDINAL GRADE

Measured over 25 m length

CROSS FALL or CAMBER

SURFACE IRREGULARITY

Measured by 3-m straight-edge

+ 20mm

-20mm to +0 mm

+ 0.1%

+ 0.3%

20 mm

(b) The surface of all constructed Granular Subbase layers shall not have any irregularities that can hold moisture. The camber of all such surfaces shall comply with that shown on the Drawings.

(c) When testing the irregularity of Granular Subbase surfaces to be treated with bituminous surfacing, all loose material shall be removed by hard brooming.

4. SUBMITTALS

The Contractor shall submit the following to the Engineer at least 21 days prior to the proposed date of first using any material proposed for use as Granular Subbase:

(a) One sample of 50 kg weight of the material for every 500m3 of material, one of which shall be retained by the Engineer for reference throughout the Contract Period;



(b) a statement of the origin and composition of any material proposed for use, together with laboratory test data for every sample verifying that the material properties specified in this Section are met.

The Contractor shall submit the following in written form to the Engineer immediately following completion of each section of the work and before any approval may be granted for the placing of other materials on top of the Granular Subbase:

(a) the results of testing as specified in Subsection 9 of this Specification Section.

(b) the results of surface measurement tests and survey data verifying that the surface and thickness tolerances shown on Table 1 are met.

5. RECTIFICATION OF UNSATISFACTORY GRANULAR SUBBASE

(a) Areas with thickness or surface uniformity not satisfying the tolerances specified in, or that develop irregularities in the surface during or after construction, shall be rectified by loosening the surface and removing or adding material as required, followed by reshaping and recompacting.

(b) Granular Subbase which is too dry for compaction, in terms of the moisture content limits as specified in or as directed by the Engineer, shall be corrected by scarifying the material followed by sprinkling with an adequate quantity of water and thoroughly mixing by means of equipment approved by the Engineer.

(c) Granular Subbase which is too wet for compaction, as defined by the moisture content limits specified in or as directed by the Engineer, shall be rectified by scarifying the material followed by intermittent working by motor grader or other approved equipment to air-dry the material under dry weather conditions. Alternatively, or if sufficient drying cannot be achieved by re-working the loose material, the Engineer may direct that the material be removed from the work and replaced with suitably dry material.

(d) Granular Subbase which becomes saturated from rain or flooding or otherwise after it has already been satisfactorily compacted according to this Specification section will generally require no rectification work provided its material properties and surface uniformity meet the requirements of this Specification section.

(e) Rectification of Granular Subbase, which does not meet the density or material property requirements of this Specification section shall be as directed by the Engineer and may include additional compaction, loosening followed by moisture content adjustment and recompaction, removal and replacement of the material, or the use of an additional thickness of material.



6. EQUIPMENT USED FOR GRANULAR SUBBASE

(a) Equipment and method used shall place the Granular Subbase to the line, levels, grades, dimensions and cross-section shown in the Drawings and as directed by the Engineer.

(b) The Engineer has the right to stop the use of any equipment or plant which he deems to be inferior to the quality required and to instruct the removal of such equipment and to have it replaced by suitable equipment or to alter the method of operation at any time.

(c) The Contractor shall immediately comply with such instructions without being entitled to any indemnities or extensions as a result of such instructions. The Contractor shall not be allowed to use any equipment or plant before obtaining the approval of the Engineer, and the Contractor shall undertake to follow sound technical methods in operation and to engage skilled and trained operators, mechanics and labor to carry out the Works. The Engineer has the right to expel any operators, mechanics or labor and to instruct suitable replacement thereof at any time he deems such action is necessary.

7. PLACING, SPREADING AND COMPACTING GRANULAR SUBBASE

Granular Subbase shall not be placed, spread or compacted while rain is falling, and no compaction shall be carried out when moisture content of the material falls outside the specified range.

7.1 PLACING

(a) The Granular Subbase material shall be placed in accordance with Drawing requirements as a uniform mixture in a quantity, which will provide the required, compacted thickness. Where shoulder material thickness is less than 100mm, the underlying surface shall be lightly scarified at no additional cost to ensure the total thickness of compacted material is at least 100mm.

(b) When more than one layer is required, each layer shall be compacted as specified in Sub-Section 7.3(e) of this Specification section, before the succeeding layer is placed.

(c) The placing of material shall begin at the point designated by the Engineer.

(d) Hauling equipment may be routed over completed portions of the subbase and provided no damage results and provided that such equipment is routed over the full width of the course to avoid rutting or uneven compaction. The Engineer has the right to stop all hauling over completed or partially completed subbase when in his opinion such hauling is causing damage.



7.2 SPREADING

(a) Where the required thickness is 150mm or less, the material may be spread and compacted in one layer. Where the required thickness is more than 150mm, the Granular Subbase shall be spread and compacted into two or more layers of approximately equal thickness, and the maximum compacted thickness of any one layer shall not exceed 150mm unless otherwise directed by the Engineer. All subsequent layers shall be spread and compacted in a similar manner.

(b) Granular Subbase shall be delivered to the roadbed as a uniform mix and shall be spread at moisture contents within the range specified in this Specification section. The moisture shall be uniformly distributed throughout the material.

(c) Granular Subbase shall be spread and shaped by any approved method, which does not cause segregation of the fine and coarse aggregate particles. Segregated material shall be corrected or removed and replaced with graded material.

(d) Immediately following final spreading and smoothening, each layer shall be compacted to the full width by means of approved compaction equipment. Rolling operations shall begin along the edges and progress gradually towards the center, in a longitudinal direction. On super-elevated sections rolling shall begin at the low side and progress towards the high side. The rolling operation shall continue until all roller marks are eliminated and the layer is uniformly compacted and the aggregates firmly keyed. Any irregularities or depressions that develop shall be corrected by loosening the material at these places and adding or removing material until the surface is smooth and uniform. Along curbs, headers, and walls, and at all places not accessible to the roller, the subbase and base material shall be compacted thoroughly with approved tampers or compactors. At the end at each shift, the surface of the base and subbase shall be shaped and sloped to prevent ponding of rainwater.

(e) Surfaces, which are to receive a prime coat, shall then be further compacted to produce a stable, tightly locked surface, without open pores, suitable for priming. All coarse aggregate shall be tightly locked in place. Under no circumstances shall any form of soil or fine aggregate be added to the surface to assist the locking process, which shall be achieved by compaction only. Vibration shall not be used in the final stages of the compaction of the surface. The Engineer may direct that pneumatic rollers be used for the final surface compaction, if static steel wheeled rollers are considered likely to cause excessive breakdown or degradation of the granular subbase.



7.3 COMPACTION

(a) Compaction shall be carried out only when the moisture content of the material is within the range of 3% less than optimum moisture content to 2% more than optimum moisture content, where the optimum moisture content is as defined by the maximum modified dry density determined by AASHTO T 180, Method D.

(b) When the underlying material is soft or yielding the subbase and base course, compaction shall be stopped and the underlying materials rectified as directed by the Engineer.

(c) During all the operations of spreading, compacting and leveling of Granular Subbase, care must be taken so that layers already compacted under the layer being executed are not affected, or that the finished subgrade or base surface is also not affected. Special attention must be given in places where equipment makes turns in going back and forth. Any such damage resulting in mixing the various layers constituting the different subgrades and base courses shall be carefully made good by the Contractor and at his expense and to the satisfaction of the Engineer.

(d) If the layer of Granular Subbase material, or part thereof, does not conform to the required finish, the Contractor shall, at his own expense, make the necessary corrections.

(e) Compaction of each layer shall continue until a field density of at least 98 percent of the maximum dry density determined in accordance with AASHTO T180, Method D, has been achieved. In-place density determination shall be made in accordance with AASHTO T 191.

8. CONTROL OF TRAFFIC ON GRANULAR SUBBASE SURFACES

(a) Construction or other traffic shall not be permitted to travel on any Granular Subbase layers, prior to the construction of the final surfacing, except where directed or permitted by the Engineer.

(b) The Granular Subbase shall not be opened to traffic until shaping and compaction is substantially complete.

(c) Pending the construction of the final surfacing, the Granular Subbase shall be maintained as follows:

♦ The Granular Subbase shall be maintained at all times by drag brooming. The traffic shall be controlled by temporary speed restrictions and, during working hours, it shall be channeled by



suitably defined traffic lanes, with frequent transverse shift of the defined lanes to obtain an even spread of traffic over the entire surface.

♦ Where the pavement course is too dry, so that surface stability does not or is unlikely to improve under the effect of traffic and/or rolling and where rain is not imminent or has been insufficient, a uniform application of water shall be applied to the entire surface. Up to 4 liters/square meter shall be applied in gradual increments so as to avoid flooding or scouring the surface.

9. TESTING

(a) The amount of supporting test data required for initial approval of the quality of the material will be as directed by the Engineer, but will include all the tests specified in this Section on at least three representative samples from the proposed material source, selected to represent the range of material quality likely to be obtained from the source.

(b) Following approval of the quality of a proposed material, the full range of material quality tests performed will be repeated subsequently, at the discretion of the Engineer, in the event of observed changes in the material or in its source or in its method of production.

(c) A program of routine material quality control testing will be carried out to control variability of the material being brought on site. The extent of the testing shall be directed by the Engineer, but for every 3000 cubic meters of material produced the testing shall include no less than five (5) plasticity index tests, five (5) particle grading tests, and one (1) maximum dry density determination using AASHTO T 180, Method D. CBR tests shall be carried out from time to time as directed by the Engineer.

(d) The density and moisture content of the compacted material shall be routinely determined, using AASHTO T 191. The test shall be made to the full depth of the layer at locations as directed by the Engineer, but not less than 200 m apart.

(e) All holes in the finished work made by density testing or otherwise shall be backfilled with the specified material by the Contractor without delay and compacted to the density and surface tolerance requirements of this Specification section.

10. MATERIALS REQUIREMENTS

10.1 MATERIAL SOURCES

All materials shall be tested and approved by the Engineer before use. The Contractor shall notify the Engineer of the sources of materials and the Engineer



will approve the sources prior to delivery of materials to the Site. Where the source of material does not meet Specification requirements, the Contractor shall furnish material from other sources. Delivery of materials produced from commercial manufacturing processes shall be accompanied by the manufacturer’s certification and test report showing the materials comply with the Specification requirements. The Engineer’s approval of a source does not imply that all the material in that source is approved.

10.2 STORAGE, MIXING AND HANDLING OF MATERIALS

(a) Materials shall be so stored and handled as to assure the preservation of their quality and fitness for construction. Materials even though approved before storage or handling, may again be inspected and tested prior to use. Stored material shall be located to facilitate prompt inspection.

(b) Handling and stockpiling of aggregates shall be to the approval of the Engineer and at all times be such as to eliminate segregation of the various sizes and contamination.

(c) Aggregate stockpiles for Granular Subbase shall be protected from rain to prevent saturation of the aggregates which would result in a reduction in the quality of the placed material or adversely affect the placement of the material

(d) Where separate size materials are to be blended to meet the gradation, such blending shall be as directed by the Engineer and shall be accomplished prior to delivery to the roadway. Mixing of separate materials on the roadway by motor grader will not be permitted.

10.3 UNACCEPTABLE MATERIALS

Materials that do not comply with the requirements of this Specification section shall be rejected and removed immediately from the site of the Works unless otherwise instructed by the Engineer. No rejected materials, the defects of which have been corrected, shall be used until the Engineer has given approval.

10.4 GRANULAR SUBBASE MATERIAL REQUIREMENTS

(a) Granular Subbase shall consist of hard, durable particles or fragments of crushed stone, crushed slag, or crushed or natural gravel and filler of natural or crushed sand or other finely divided mineral matter. The composite material shall be free from vegetable matter and lumps or balls of clay, and shall be of such nature that it can be compacted readily to form a firm, stable base.

(b) Granular Subbase material gradation shall conform to Table 2.



Table 2

Grading Requirements for Granular Subbase

Sieve Designation Mass Percent Passing

Standard (mm) Alternate US Standard

50 2 inch 100

25 1 inch 55-85

9.5 3/8 inch 40-75

0.075 No.200 0-12

Granular Subbase shall conform to the properties given in Table 3.

Table 3

Granular Subbase Properties Properties Granular Subbase

Abrasion of Aggregate retained on 2.00 mm (No.10) sieve (AASHTO T 96)

50% max.

Plasticity Index of Aggregate passing the 0.425 mm (No. 40) sieve (AASHTO T 90)

6 max*

(5-6 for shoulder).

Percent by weight of Aggregate retained on 2mm (No.10) sieve with one fractured face

-

Liquid Limit of Aggregate passing the 0.425 (No. 40) sieve (AASHTO T 89)

35 max.

Soaked CBR (AASHTO T 193) at maximum dry density according to AASHTO T 180 Method D

30% min.


11.1 MEASUREMENT

(a) Granular Subbase shall be measured as the number of cubic meters of compacted material required, complete in place and accepted. The volumes to be measured shall be based on the cross sections shown on the drawings and approved by the Engineer and lengths measured horizontally along the road centerline. No allowance will be given for materials placed outside the design limits shown on the cross-sections.



(b) The work of preparing and maintaining the subgrade on which the granular subbase is to be placed shall be addressed in accordance with requirements and stipulations of Specification section 03400 “Subgrade Preparation”.

(c) No separate measurement for payment will be made for any Running Course gravel used for temporary protection of the surface of Granular Subbase exposed to traffic.

(d) No additional measurement for payment will be made for repairs to layers caused by traffic or natural conditions.

(e) No additional measurement for payment will be made for extra material provided in the next course for a deficiency in the subbase or base course.

11.2 MEASUREMENT OF RECTIFIED WORK

(a) Where rectification of unsatisfactory Granular Subbase has been directed by the Engineer, the quantities to be measured for payment shall be those, which would have, been paid if the original work had been acceptable. No additional payment will be made for the extra work or quantities necessitated by the rectification.

(b) Where adjustment of moisture content has been directed by the Engineer prior to compaction, no additional payments will be made for adding water or drying out the material or for any other work required to obtain a satisfactory moisture content.

11.3 PAYMENT

The quantities determined, as provided above, shall be paid for in accordance with Unit Prices as indicated on the Bill of Quantities for each of the particular Pay Items. Payment shall be full compensation for hauling, supplying, placing, compacting, finishing and testing the materials, the supply and placing of running course and maintenance of the surface under traffic, and all other costs necessary or usual to the proper completion of the work prescribed in this Specification section.


Unit

R-03965-1 Granular Subbase m3


DIVISION 4 - DRAINAGE WORKS Ditches and Paved Waterways - Section 04100

SECTION 04100 - DITCHES AND PAVED WATERWAYS

TABLE OF CONTENTS

1. GENERAL.................................................................................................................................................. 1

1.1 DESCRIPTION ............................................................................................................................................... 1

1.2 SHOP DRAWINGS......................................................................................................................................... 1

1.3 DIMENSIONAL TOLERANCES....................................................................................................................... 1

1.4 SUBMITTALS ................................................................................................................................................. 1

1.5 WORK SCHEDULING.................................................................................................................................... 2

1.6 RECTIFYING UNSATISFACTORY WORK ....................................................................................................... 2

1.7 MAINTENANCE OF ACCEPTED WORK ........................................................................................................ 2

2. MATERIALS ............................................................................................................................................. 3

2.1 FILL .............................................................................................................................................................. 3

2.2 MORTARED STONEWORK ............................................................................................................................ 3

2.3 GRANULAR BEDDING MATERIAL................................................................................................................ 3

2.4 CRUSHED STONE ......................................................................................................................................... 3

2.5 CONCRETE WORK........................................................................................................................................ 4

3. EXECUTION OF THE WORK ............................................................................................................... 4

3.1 SETTING OUT ROADSIDE DITCHES.............................................................................................................. 4

3.2 ROADSIDE DITCHES CONSTRUCTION.......................................................................................................... 4

3.3 PRESERVATION OF EXISTING WATERWAYS................................................................................................. 4

3.4 PRESERVATION OF WATER CONTROL STRUCTURES ................................................................................... 5

3.5 REALIGNING EXISTING WATERWAYS ......................................................................................................... 5

3.6 IRRIGATION CHANNEL RELOCATION ......................................................................................................... 5


4.1 PAYMENT ..................................................................................................................................................... 5

4.2 BASIS OF PAYMENT...................................................................................................................................... 6



SECTION 04100 - DITCHES AND PAVED WATERWAYS

1. GENERAL

1.1 DESCRIPTION

This work shall consist of constructing new lined and unlined waterways and roadway drainage ditches. This work shall be in accordance with the lines, levels, and details shown on the Drawings or as directed by the Engineer. The Contractor shall construct lined roadside ditches using mortared stonework or reinforced concrete as shown in the Drawings, unless otherwise directed by the Engineer.

1.2 SHOP DRAWINGS

The Contractor shall furnish shop drawings containing the construction details for lined and unlined waterways indicated on the Drawings and as directed by the Engineer. Shop drawings shall be submitted to the Engineer prior to the start of the construction. Construction of the waterways and ditches shall begin only after the Engineer has given his approval.

1.3 DIMENSIONAL TOLERANCES

(a) Finished grades on new roadside ditches inverts shall not vary from those specified or approved by more than 5 mm at any point.

(b) Finished new roadside ditches alignments and the shape of cross sections shall not vary from those specified in the drawings by more than 2 cm at any point.

(c) Finished grades on realigned waterway inverts shall not vary by more than 1 cm from the existing invert levels. The finish shall be sufficiently smooth and uniform to ensure the free flow of water without ponding during periods of low flow.

(d) The alignment and shape of cross sections for realigned existing waterways shall not vary from those specified in the drawings by more than 5 cm at any point.

(e) The Contractor shall notify the Engineer after completing all waterway formations. No lining work shall begin until the Engineer approves the formation.

1.4 SUBMITTALS

The Contractor shall submit samples of materials he intends to use for waterway lining to the Engineer for approval.



1.5 WORK SCHEDULING

(a) The Contractor shall schedule waterway construction work to ensure adequate drainage of the Works. Temporary drainage work shall be in place and operating before beginning embankment works, or as directed by the Engineer.

(b) The Contractor shall first trim roadside drains short of the approved cross sections.

(c) The Contractor shall complete the final trimming as well as any repair or damage that may have occurred during construction after completing all other immediately adjacent or interfacing work.

1.6 RECTIFYING UNSATISFACTORY WORK

(a) The Contractor shall rectify all waterway construction work that does not meet the tolerance criteria given in Subsection 1.3 of this Specification section or that the Engineer rejects as unacceptable. The Contractor shall rectify unacceptable work as directed by the Engineer.

(b) The Contractor shall repeat survey work defining existing or constructed surface profiles as often as necessary to obtain an accurate record of the physical conditions.

(c) Rectification work may include:

♦ additional excavation or fill, which could include backfilling new work and re-excavating it to the specified dimensions, lines, and grades, and

♦ repairing or replacing defective mortared stonework or reinforced concrete work.

No additional payment will be made for the extra work or quantities necessitated by the rectification.

1.7 MAINTENANCE OF ACCEPTED WORK

Notwithstanding the Contractor’s obligation to rectify unsatisfactory or failed work in accordance with sub-section 1.6 of this Specification section, the Contractor shall also be responsible for routine maintenance of all completed and accepted new waterways throughout the Contract Period. No separate measurement or payment shall be made for such routine maintenance.



2. MATERIALS

2.1 FILL

Fill shall conform to the requirements for material properties, placing, compacting and quality assurance specified in Specification section 03400 “Embankment Construction”. Erosion resistant material approved by the Engineer shall be used.

2.2 MORTARED STONEWORK

Mortared stone lining shall conform to the requirements for material properties, placing, compacting and quality assurance specified in Specification section 04200 “Mortared Stone Work”.

2.3 GRANULAR BEDDING MATERIAL

Granular bedding material shall consist of natural sand or crushed sand, having hard, strong, durable particles meeting the following grading requirements:

Sieve Size (mm) Percent Passing by weight

9.5

4.75

2.36

1.18

0.600

0.300

0.150

100

95 - 100

80 - 100

50 - 85

25 - 60

5 - 30

2 - 10

2.4 CRUSHED STONE

Crushed stone shall be crushed aggregate free from extraneous materials, clay lumps, and organic matter. It shall meet the following grading requirements.

Sieve Size (mm) Percent Passing by weight

25 100

19 90 - 100

12.5 30 - 70

4.75 0 - 10



2.5 CONCRETE WORK

Concrete work shall conform to the requirements for material properties, placing, curing, and quality assurance specified in Specification Section 06100 “Concrete and Concrete Structures”. Concrete shall be the class as indicated on the drawings. Reinforcing steel if required shall be in accordance with Specification section 06400 “Reinforcing Steel”.

3. EXECUTION OF THE WORK

3.1 SETTING OUT ROADSIDE DITCHES

The Contractor shall set out the required locations, lengths, direction of fall, and grades of all ditches, whether lined or unlined. Setting out shall include locating all associated catch pits and out falls.

3.2 ROADSIDE DITCHES CONSTRUCTION

(a) The Contractor shall excavate, fill, and trim the realigned and new roadside drains to the grades shown on the construction drawings and to the profiles shown on the typical drawings of side drains or as otherwise directed by the Engineer.

(b) The Contractor shall construct the linings for roadside drains after the Engineer approves the prepared roadside drain formations.

(c) The Contractor shall remove and dispose of all excavation material to at least 10 meters from the waterway area to prevent any surplus material from falling into the excavated waterway.

3.3 PRESERVATION OF EXISTING WATERWAYS

(a) The Contractor shall not disturb natural streams or channels as well as irrigation canals and drains adjacent to the works of this Contract without the approval of the Engineer and local authorities. Irrigation canals shall not be disturbed without the permission of the local People’s Committee or Irrigation Company that is responsible for their operation and maintenance.

(b) If the Contractor cannot avoid excavating or dredging in an existing waterway for the proper execution of the works, he shall backfill all such excavation to the original ground elevations and shapes with material approved by the Engineer after completing construction.

(c) The Contractor shall remove material deposited within the waterway area resulting from foundation excavation, constructing cofferdams, or other related works following construction.



3.4 PRESERVATION OF WATER CONTROL STRUCTURES

The Contractor shall not disturb existing water control structures adjacent to the works of this Contract without the approval of the Engineer and local authorities. These structures shall include existing culverts, canal inlets, regulators, gates, pumping stations, etc. Water regulation structures for irrigation shall not be disturbed without the permission of the local People’s Committee or Irrigation Company that is responsible for their operation and maintenance.

3.5 REALIGNING EXISTING WATERWAYS

(a) Where embankment stabilization or other permanent works of the Contract will unavoidably block, or partially block, any existing waterway, the waterway shall be relocated to ensure unrestricted flow past the works at all usual irrigation supply and flood control levels.

(b) Waterway realignments, whether temporary or permanent, shall preserve the existing channel invert levels. Realigned waterways shall be located so that expected flows will not cause detrimental scour or erosion of the works or nearby property.

(c) The Contractor shall be responsible for maintaining the design flow and water levels in all temporarily relocated irrigation canals throughout the Contract period. The Contractor shall be responsible for any additional pumping or other related works for maintaining these irrigation facilities at his own expense.

3.6 IRRIGATION CHANNEL RELOCATION

In accordance with the drawing requirements ditches shall be constructed for the relocation of channels. Such work shall include excavation of ditches to the depth and shape required, along with the deposition and shaping of excavated materials along the edge as shown on the drawings.


4.1 PAYMENT

Ditches shall be measured for payment based on the length, in linear meters, of competed and approved ditch in accordance with drawing requirements or as required by the Engineer.

Concrete ditch lining plates (50 x 50 x 6cm) shall be measured in cubic meters based on the required thickness of the plates and completed and accepted area of placement, measured across mortared joints.



4.2 BASIS OF PAYMENT

There will be no separate payment for excavation, backfill, bedding, mortar and lining of ditches under this Specification section, except for concrete lining plates. Ditches and irrigation ditch relocation shall be paid for in accordance with applicable Unit Prices as indicated on the Bill of Quantities. The Unit Price for each Pay Item shall be full compensation for all preparatory works, labor, equipment, supplying, transporting and placing and compacting all materials necessary to complete the work.

Pay Item Description Unit

D-04100-2 Stone masonry to drain m3

D-04100-3 Concrete drain m3


DIVISION 4 - DRAINAGE WORKS Mortared Stonework - Section 04200

SECTION 04200 - MORTARED STONEWORK

TABLE OF CONTENTS

1. GENERAL.................................................................................................................................................. 1

1.1 DESCRIPTION ............................................................................................................................................... 1

1.2 SHOP DRAWINGS......................................................................................................................................... 1

1.3 DIMENSIONAL TOLERANCES....................................................................................................................... 1

1.4 SUBMITTALS AND APPROVALS.................................................................................................................... 1

1.5 WORK SCHEDULING.................................................................................................................................... 2

1.6 WORK SITE CONDITIONS............................................................................................................................. 2

1.7 RECTIFYING UNSATISFACTORY OR FAILED WORK ..................................................................................... 2

1.8 MAINTAINING ACCEPTED WORK ............................................................................................................... 2

2. MATERIALS ............................................................................................................................................. 2

2.1 STONE .......................................................................................................................................................... 2

2.2 MORTAR....................................................................................................................................................... 3

2.3 SAND BEDDING............................................................................................................................................ 3


3.1 PREPARING FORMATIONS OR FOUNDATIONS............................................................................................. 4

3.2 PREPARING STONE....................................................................................................................................... 4

3.3 PLACING STONE LINING ............................................................................................................................. 4

3.4 CONSTRUCTING MORTARED STONEWORK STRUCTURES ........................................................................... 5


4.1 MEASUREMENT............................................................................................................................................ 5

4.2 PAYMENT ..................................................................................................................................................... 5



SECTION 04200 - MORTARED STONEWORK

1. GENERAL

1.1 DESCRIPTION

This work shall consist of lining the sides and bottoms of roadside drains and waterways, as well as, constructing aprons, catch pits, and other similar small water control structures with mortared stone. All work constructed on prepared beds shall be in accordance with this Specification Section and conform with the lines, grades, and dimensions shown on the Drawings or otherwise directed by the Engineer.

1.2 SHOP DRAWINGS

The Contractor shall furnish shop drawings containing the constructions details for mortared stonework indicated on the Drawings and as directed by the Engineer. Shop drawings shall be submitted to the Engineer prior to the start of the construction of mortared stonework. Construction of mortared stonework shall begin only after the Engineer gives approval of the shop drawings to the Contractor.

1.3 DIMENSIONAL TOLERANCES

(a) The surface of each face stone shall not vary from the average profile of the surrounding stonework by more than 3 cm.

(b) The average surface profile for waterway lining formed by placed stonework shall not vary from the specified or approved channel invert profile by more than 2 cm.

(c) The minimum thickness of any mortared stonework lining shall be 10 cm.

(d) The finished profiles for minor, non-load bearing structures such as catch pits and spillway aprons shall not vary from the specified or approved profiles by more than 2 cm.

1.4 SUBMITTALS AND APPROVALS

The Contractor shall submit to the Engineer two representative stone samples for each class before using any stone material in mortared stonework. The Engineer will retain one of these samples for reference throughout the Contract Period. The Contractor shall only use stone for the works that the Engineer approves.



1.5 WORK SCHEDULING

The Contractor shall limit the extent of mortared stonework he carries out at any time to ensure that all stones are placed only in fresh mortar.

Where mortared stonework paving is to be constructed on slopes or as roadside drain lining, the Contractor shall first form the slopes as if there were to be no paving. The Contractor shall shape the work to the final lines only immediately before placing the stonework.

1.6 WORK SITE CONDITIONS

A dry work site should be maintained and adequate sanitation facilities should be available for the workmen.

1.7 RECTIFYING UNSATISFACTORY OR FAILED WORK

The Contractor shall rectify at his own expense mortared stonework which does not meet the tolerances given in this Specification Section or as directed by the Engineer.

The Contractor shall be responsible for the stability and integrity of all finished work. The Contractor shall replace at his own expense any damaged or displaced portions due (in the opinion of the Engineer) to the Contractor’s carelessness or neglect.

1.8 MAINTAINING ACCEPTED WORK

Notwithstanding the Contractor’s obligation to rectify unsatisfactory or failed work. The Contractor shall also be responsible for routine maintenance of all completed and accepted mortared stonework throughout the Contract Period and the Defect Liability Period. No separate measurement or payment shall be made for such routine maintenance.

2. MATERIALS

2.1 STONE

Stones shall consist of angular fieldstone or rough quarry stone which is sound, tough, durable, dense, resistant to the action of air and water, and suitable in all respects for the purpose intended. If the contractor wishes to use rounded material, this shall be restricted to 30% of total material and broken on at least two faces.

The Engineer shall approve the quality and dimensions of the stones prior to use. Stones for paving roadside drains shall be as nearly rectangular in shape as practicable. Unless otherwise indicated in the Drawings or directed by the Engineer, the stone should meet the gradation requirements in Table below 1.



TABLE 1

Gradation Requirement for Stones

Approximate Given Size Nominal

Thickness

(mm)

Weight

(kg)

Volume

(cu.m.)

Equivalent Cubic

Dimension

(mm)

Total Size Smaller

than Given Size

(%)

15 .006 175 100

10 .004 150 80

5 .002 125 50

150

0.5 .0003 50 10*

45 .018 250 100

27 .011 225 80

11 .005 165 50

250

2 .0003 75 10*

*Material shall consist of spalls and rock fragments graded to provide a stable compact mass.

For larger thicker masonry sections, at least 10% of stones shall be bond stones of at least 20x20x50cm, uniformly distributed and laid from the front/rear faces, perpendicular to the long axis of the structure or as directed by the Engineer.

2.2 MORTAR

Mortar shall be in accordance with the provisions and requirements of Specification Section 08010 “Cement Mortar”.

2.3 WEEPHOLE PIPES

Pipes shall be 150mm nominal dia. Heavy duty PVC (minimum wall thickness 5mm), wrapped at the inner end with one layer of geotextile to Specification 04500.

2.4 SAND BEDDING

Materials for forming bedding, weep holes or filter pockets for mortared stonework shall conform to the requirements conforming to the gradations of ASTM C33.




3.1 PREPARING FORMATIONS OR FOUNDATIONS

(a) The Contractor shall prepare formations for mortared stonework paving in accordance with the provisions of Specification Section 04100, “Ditches and Paved Waterways”.

(b) The Contractor shall prepare foundations and trenches for cut-off walls or other structures made of mortared stonework in accordance with the provisions of Specification Section 03200, “Structure Excavation” and Specification Section 03400 “Embankment Construction”.

3.2 PREPARING STONE

(a) The Contractor shall clean the stones of all defects that may impair the bond with the mortar.

(b) The Contractor shall thoroughly wet the stones long enough for the stones to absorb water to near saturation prior to laying.

3.3 PLACING STONE LINING

(a) The Contractor shall place a bedding of fresh mortar at least 3 cm thick on the prepared formation. The Contractor shall construct this mortar bedding progressively by laying the surface stones in such a manner that the stones are always securely bedded in the mortar before it hardens.

(b) The Contractor shall place the stones firmly against each other to provide the required paving thickness measured perpendicular to the slope. The Contractor shall then place additional mortar to fill ALL spaces between the stones completely. The finish shall be almost flush with the surface of the lining but the mortar shall not cover the stones.

(c) PVC weepholes with outward fall are to be incorporated into the masonry at 2m c/c triangular grid or as otherwise directed.

(d) The work shall progress from the bottom of the slopes towards the top. The Contractor shall finish the surface immediately following the initial set of the mortar by sweeping the surface with a stiff broom.

(e) The Contractor shall cure the finished surfaces as specified for concrete work in Specification Section 06100 “Concrete and Concrete Structures”.

(f) The Contractor shall trim and finish adjacent slopes and shoulders to ensure a tight and smooth interface with the mortared stonework. The interfaces



shall allow unobstructed drainage and prevent scour at the edges of the work.

3.4 CONSTRUCTING MORTARED STONEWORK STRUCTURES

(a) The Contractor shall construct the cut-off walls by filling the trench or forms with mortar to a depth of 60% of the maximum dimension of the stones. The Contractor shall then place the stones in the unset mortar immediately. The Contractor shall add additional mortar and repeat the process until the form is filled. The Contractor shall then add mortar to the top of the cut-off until he obtains a screeded level top surface.

(b) The Contractor may construct mortared stonework structures without forms if the stone can interlock sufficiently and if he uses stiff mortar.

(c) The Contractor shall finish and cure exposed surfaces of mortared stonework structures as specified in Specification Section 06100 “Concrete and Concrete Structures”.

(d) The Contractor shall backfill around the finished and cured stone masonry structures in accordance with the provisions of Specification Section 03400 “Embankment Construction”.


4.1 MEASUREMENT

(a) Mortared Stone, when used in ditches, shall not be measured for payment. Instead, the cost shall be incorporated for the unit price of paved ditches as provided for in Specification Section 04100 “Ditches and Paved Waterways”.

(b) When used in aprons, headwalls and catch pits for culverts and other water control structures other than roadside ditches, Mortared Stone shall measured by cubic meters of nominal volume of completed and accepted work. The nominal volume is defined as the product of the area of exposed surface and the nominal thickness of lining as shown in the drawings.

(c) Excavations for aprons and catch pits lined with mortared stonework shall be measured and paid in accordance with provisions of Specification Section 03200 “Structural Excavation”.

4.2 PAYMENT

The quantity of mortared stonework shall be paid for in accordance with applicable Unit Price as indicated on the Bill of Quantities. Payment shall be full compensation for supplying, transporting, and placing all materials for mortared stonework including:



♦ forming and preparing foundations;

♦ constructing weep holes;

♦ dewatering works;

♦ finishing; and

♦ all other works necessary or usual for completing mortared stonework described in this Specification section.


DIVISION 4 - DRAINAGE WORKS Pipe Culverts, Box Culverts & Drainage Structures - Section 04330

SECTION 04330 – PIPE CULVERTS, BOX CULVERTS AND DRAINAGE STRUCTURES

TABLE OF CONTENTS

1. DESCRIPTION......................................................................................................................................... 1

2. SHOP DRAWINGS ................................................................................................................................. 1

3. SUBMITTALS........................................................................................................................................... 1

4. SCHEDULING AND SPECIAL SEQUENCING REQUIREMENT................................................ 1

5. RECTIFYING UNSATISFACTORY WORK....................................................................................... 2

6. MAINTAINING ACCEPTED WORK.................................................................................................. 2

7. MATERIALS ............................................................................................................................................. 2

7.1 BEDDING ..................................................................................................................................................... 2

7.2 CONCRETE ................................................................................................................................................... 2

7.3 REINFORCING STEEL FOR CONCRETE.......................................................................................................... 2

7.4 REINFORCED CONCRETE CULVERT PIPES ................................................................................................... 2

7.5 MORTAR ..................................................................................................................................................... 3

7.6 POROUS BACKFILL OR FILTER MATERIAL ................................................................................................... 3

7.7 BACKFILL ..................................................................................................................................................... 3

7.8 RIP-RAP ..................................................................................................................................................... 3

7.9 WATER STOPS .............................................................................................................................................. 3

7.10 MANHOLE COVERS, CATCH BASINS, AND FRAMES................................................................................... 4

7.11 MANHOLE LADDER RUNGS ........................................................................................................................ 4


8.1 HANDLING................................................................................................................................................... 4

8.2 SITE PREPARATION ...................................................................................................................................... 4

8.3 PLACING REINFORCED CONCRETE CULVERT PIPES ................................................................................... 4

8.4 CONSTRUCTING BOX CULVERTS ................................................................................................................. 6

8.5 EXTENSION OF EXISTING CULVERTS ........................................................................................................... 6



8.5.1 PIPE CULVERT EXTENSIONS ..........................................................................................................................6

8.5.2 BOX CULVERT EXTENSIONS.........................................................................................................................7

8.6 CLEANING CULVERTS..................................................................................................................................7

8.7 CULVERT HEADWALLS, INLETS, AND OUTLETS .........................................................................................7

8.8 PLACING WATER STOPS ..............................................................................................................................8

9. MEASUREMENT AND PAYMENT.....................................................................................................8

9.1 MEASUREMENT............................................................................................................................................8

9.1.1 CONCRETE PIPE CULVERTS ...........................................................................................................................8

9.1.2 CONCRETE BOX CULVERTS...........................................................................................................................8

9.1.3 CATCH BASINS..............................................................................................................................................9

9.1.4 MANHOLES ...................................................................................................................................................9

9.2 PAYMENT .....................................................................................................................................................9

Rehabilitation of Kabul-Dushi Highway, Afghanistan 02/04/03 04330 - ii


SECTION 04300 – PIPE CULVERTS, BOX CULVERTS AND DRAINAGE STRUCTURES

1. DESCRIPTION

This work shall consist of constructing new reinforced concrete pipe and box culverts and drainage structures and extensions of existing pipe and box culverts. This work shall include drainage catch basins, headwalls, inlet and outlet structures as well as associated erosion and scour protection. All of these works shall be in accordance with the drawings and this Specification and at the locations noted on the drawings or indicated by the Engineer.

The work shall include furnishing and constructing joints and such connections to other pipes, catch basins, walls and/or other items as shown on the drawings or as required by the Engineer.

2. SHOP DRAWINGS

The Contractor shall furnish shop drawings containing the construction details for culverts and concrete drains indicated on the drawings and as directed by the Engineer. Shop drawings shall be submitted to the Engineer prior to the start of the construction of culverts and concrete drains. Construction of the culverts and drains shall begin only after the Engineer gives his approval.

3. SUBMITTALS

Certifications from the manufacturers attesting that material meets specification requirements shall be submitted to the Engineer for approval no later than 60 days prior to the intended commencement of work. Certificates are required for all drainpipe, fittings, manhole covers and frames, and drainage grates and frames.

4. SCHEDULING AND SPECIAL SEQUENCING REQUIREMENT

(a) The Contractor shall not begin culvert work until the Engineer issues the written approval and scope of works. The Contractor shall schedule waterway construction work to ensure adequate drainage of the Works. Temporary drainage work shall be in place and operating before beginning embankment works, or as directed by the Engineer

(b) No subgrade preparation or pavement overlay work (either in the road or the shoulder areas) shall commence until the culverts, headwalls, and other minor structures below the subgrade level along that particular section of the project are complete.



5. RECTIFYING UNSATISFACTORY WORK

All work and materials for constructing culverts and drains shall conform to the dimensional tolerances and to the various provisions for rectifying unsatisfactory work that are given in the Specifications relevant to the work or material concerned.

6. MAINTAINING ACCEPTED WORK

Notwithstanding the Contractor’s obligation to rectify unsatisfactory or failed work, the Contractor shall also be responsible for routine maintenance of all completed and accepted culverts and drains throughout the Contract Period and the Defect Liability Period. No separate measurement or payment shall be made for such routine maintenance

7. MATERIALS

7.1 BEDDING

(a) Bedding material for pipes and concrete drains (including sand bedding as indicated on the drawings) shall “Bedding Material for Pipes and Concrete Drains” in accordance with requirements and provisions of Specification section 04500 “Porous Drainage and Backfill”.

(b) Unless otherwise indicated, lean concrete or concrete bedding or blinding concrete shall be Class G concrete in accordance with the requirements and stipulations of Specification section 06100 “Concrete and Concrete Structures”.

7.2 CONCRETE

Concrete used for all structural work described in this Specification section shall be the class as indicated on the drawings and conform to the requirements stipulations of Specification section 06100, “Concrete and Concrete Structures”.

7.3 REINFORCING STEEL FOR CONCRETE

All reinforcing steel used shall conform to the requirements and stipulations of Specification section 06400, “Reinforcing Steel”.

7.4 REINFORCED CONCRETE CULVERT PIPES

(a) Unless otherwise approved by the Engineer reinforced concrete pipes shall be of precast reinforced concrete and shall conform to AASHTO Specification M 170 Class III. Unless otherwise approved by the Engineer or required by drawings, the Contractor shall use pipes with tongue and groove joints. Reinforcement in all pipes shall consist of circular bars.



(b) If the Engineer approves the use of bell and spigot joint pipes, the pipe shall be in accordance AASHTO M 170 Class III and rubber gaskets shall comply with the requirements of AASHTO M198.

(c) The Engineer may inspect the pipe manufacturing plants periodically to ensure compliance with accepted manufacturing methods. The Contractor will supply material samples for laboratory testing to ensure quality compliance. The Engineer will inspect all reinforced concrete pipes before permitting the Contractor to lay any pipe.

7.5 MORTAR

Mortared joints shall only be used if required by the Engineer or so indicated on the drawings. If/when required mortar for pipe joints and collars shall be in accordance with the provisions of Specification section 08010 “Cement Mortar”.

7.6 POROUS BACKFILL OR FILTER MATERIAL

Porous Backfill or Filter Material shall be in accordance with the provisions of Specification section 03700 “Granular Backfill” or as directed by the Engineer.

7.7 BACKFILL

Fill material used in the works shall conform to the requirements specified in Specification section 03400, “Embankment Construction”.

7.8 RIP-RAP

Stone used in the works for riprap shall conform to the requirements specified in Specification section 04400, “Mortared Riprap”.

7.9 WATER STOPS

(a) When water stops are required by drawings, fabricated plastic water stop with a uniform cross section that is free from porosity and other defects, shall be used with the prior approval of the Engineer. If approved, an equivalent standard shape may be furnished.

(b) Water stops shall be fabricated from a homogeneous, elastomeric, plastic compound of basic polyvinyl chloride and other material. Reclaimed material shall not be used.

(c) The Contractor shall furnish a certification from the producer showing test values for the following properties:

♦ Tensile strength, ASTM D 638 - 9.65 Mpa

♦ Elongation at breaking, ASTM D 638- 250% min



♦ Hardness (shore), ASTM D 2240 - 60 –75

♦ Resistance to alkali, ASTM D 543 - Max. % change –0.10 to +0.25

♦ Max. Change in hardness +/-5 shore

♦ Min. Decrease in tensile strength - 15%

♦ Water Absorption, ASTM D570 - 0.50% max.

7.10 MANHOLE COVERS, CATCH BASINS, AND FRAMES

Unless otherwise approved by the Engineer, covers, frames and gratings shall be cast iron, which meet the requirements of ASTM A 48 Class 50, classified as “Heavy Duty” with shape, sizes and connection requirements as indicated on the drawings.

7.11 MANHOLE LADDER RUNGS

Manhole ladder rungs where required by drawings or the Engineer shall be 20-mm diameter galvanized steel or cast iron, sized, shaped, and spaced as shown on the drawings.


8.1 HANDLING

Materials shall be handled in such a manner as to insure delivery to the point of installation in sound undamaged condition. Pipe shall be carried and not dragged to the installation location.

8.2 SITE PREPARATION

The Contractor shall excavate and prepare trenches and foundations for concrete culverts and drains in accordance with the provisions of Specification sections 03200, “Structural Excavation” and 03400 “Embankment Construction”. The Contractor shall be responsible for all dewatering of the trenches during construction. The Contractor shall place supports and/or bedding material in accordance with drawing requirements or as required by the Engineer in conformance with applicable Specification sections.

8.3 PLACING REINFORCED CONCRETE CULVERT PIPES

(a) The Contractor shall excavate culvert trenches to the required depth. The bed shall provide a uniform and continuous support under the entire length of the pipe.

(b) The trench width shall be a plane 500 mm measured from the outer walls of the pipe. The Engineer, at his discretion, may allow extra trench widths, but



the Contractor shall receive no additional payment for the wider trench excavation.

(c) The side slopes of the trenches shall be adopted to suit the soil stability. If the Contractor over-excavates the culvert trench, he shall fill the void to the proper level with material approved by the Engineer at the Contractor’s own expense.

(d) Each pipe shall be carefully inspected before it is laid. Any defective or damaged pipe shall be rejected.

(e) No pipe shall be laid when the trench conditions are unsuitable for such work. Water shall be removed from trenches by sump pumping or other approved methods.

(f) The pipe shall be laid to the grades and alignment as indicated. The pipe shall be bedded to the established grade line. Pipes of either the bell-and-spigot type or the tongue-and-groove type shall be laid with the bell or groove ends upstream. The spigots or tongued ends shall be fully entered into the adjacent hub or groove and be true to the required lines and grades.

(g) Before laying succeeding sections of reinforced concrete pipe which do not require cambering, the Contractor shall plaster the lower half of the hub of the preceding sections on the inside with Portland cement mortar. The mortar shall be sufficiently thick to bring the inner surface of the abutting pipes flush and even. The Contractor shall plaster the upper half of the spigot of the succeeding pipe with mortar at the same time.

(h) If mortared joints are allowed or required, after laying the reinforced concrete pipe, the Contractor shall fill the remainder of the joint with sufficient mortar to form a bead around the joint. The Contractor shall wipe the inside of the joint and finish it to a smooth and even surface. The mortar on the outside shall be cured and remain damp for two days or until the Engineer allows backfilling to proceed.

(i) The Contractor shall not backfill any pipe until the Engineer inspects and approves the site conditions. The Contractor shall backfill and compact the soil around and over the reinforced concrete culvert pipes as specified herein using material conforming to the requirements given for Selected Granular Embankment. The material shall consist of soil or gravel free of clay lumps and organic matter. The backfill material shall contain no stones that would be retained on a 25 mm sieve. Oversized material shall be removed at the source of the material.

(j) The Contractor shall take the fill to a minimum height of 50 cm above the top of the pipe. Unless in a trench, the fill shall extend for a minimum distance of



one and a half diameters from the centerline of the pipe on each side of the pipe. The Contractor shall take special care to compact the backfill under the haunches of the pipe properly. The backfill shall be brought up evenly on both sides of the haunches for the entire pipe length.

(k) Heavy earth moving and compacting equipment shall not operate closer than 1.5 meters from the culvert until the cover above the pipe is at least 50 cm. Light weight equipment may operate within the limitation mentioned above provided the backfill is placed and compacted at least 30 cm above the top of the pipe. Notwithstanding these conditions, the Contractor shall be responsible for and shall rectify any damage resulting from such operations.

8.4 CONSTRUCTING BOX CULVERTS

(a) The Contractor shall construct box culverts to the lines and dimensions given on the Drawings or as the Engineer directs.

(b) Unless otherwise required, all work shall be in accordance with requirements of AASHTO M 259-95.

(c) All concrete work shall conform to the requirements of Specification section 06100, “Concrete and Concrete Structures”. All reinforcing steel shall be deformed reinforcing bars in accordance with requirements and stipulations of Specification section 06400, “Reinforcing Steel”. All excavation and backfill work shall comply with the provisions of Specification Section 03200, “Structure Excavation” and Specification section 03400 “Embankment Construction”.

8.5 EXTENSION OF EXISTING CULVERTS

8.5.1 PIPE CULVERT EXTENSIONS

(a) The extension of existing pipe culverts shall be accomplished in accordance with drawing requirements. Pipe culverts shall be extended by the method shown on the drawings to connect the initial extension pipe section to an existing pipe.

(b) Pipe extensions shall be made with new pipe only.

(c) All existing pipe culverts designated to remain or to be extended shall be examined by the Engineer and the Contractor. Pipe culverts found to be defective and unworthy of remaining or being extended shall be removed and replaced as provided for herein. All usable sections of existing pipe culverts shall be handled with extreme care, cleaned, removed from the site and stored at a location as agreed to by the Engineer. The Contractor will be held responsible for the satisfactory removal of pipe sections in a usable condition. Pipe removed shall be replaced with new sections of pipe.



Payment for this work shall be in accordance with provisions of this Specification section.

(d) Pipe joints will also inspected by the Engineer and broken joints shall be resealed.

(e) If required by the Engineer, bedding material shall be placed.

(f) Before backfilling of pipe culverts, all joints shall be mortared, and if necessary, unsuitable material shall be removed and replaced.

(g) Extended pipe culverts shall be backfilled as specified in sub-section 9.3 of this Specification section.

8.5.2 BOX CULVERT EXTENSIONS

(h) Existing Box Culverts indicated to be extended, shall be extended with a standard box section constructed in accordance with the typical details shown on the drawings.

(i) All concrete work shall conform to the requirements of Specification section 06100, “Concrete and Concrete Structures”.

(j) All reinforcing steel shall be deformed reinforcing bars in accordance with requirements and stipulations of Specification section 06400, “Reinforcing Steel”.

(k) The method of connection of the extension to the existing section shall be submitted by the contractor to the Engineer for approval, and may vary depending on the nature of the existing culvert.

8.6 CLEANING CULVERTS

The Contractor shall clean all culverts until they are free of loose debris, soil, and all foreign material. The Contractor shall keep the culverts clean and maintain them in an operating condition throughout the Contract Period. The Contractor shall only permit water to flow through the cleaned culvert after the Engineer inspects and approves the culvert.

8.7 CULVERT HEADWALLS, INLETS, AND OUTLETS

Unless otherwise shown on the drawings, the Contractor shall construct all culvert aprons, wingwalls, and headwalls using concrete of the class indicated on the drawings, and in accordance with requirements and provisions of Specification section 06100 “Concrete and Concrete Structures”.



8.8 PLACING WATER STOPS

When water stops are required by drawings, the Contractor shall carefully place and support water stops. If splicing of water stop is to be done, heat splices according to manufacturer’s instructions to make them watertight, shall be made. Splices should have a tensile strength of at least 80 percent of the reported tensile strength of the unspliced water stop. The Contractor shall prevent water stops from being displaced or damaged by construction operations and other activities, and keep all surfaces of water stops free from oil, grease, dried mortar, or any other deleterious material embedded in the concrete. The Contractor shall ensure that embedded portions of the water stop are completely enclosed in dense concrete.


9.1 MEASUREMENT

9.1.1 CONCRETE PIPE CULVERTS

(a) Reinforced concrete pipe culvert quantities to be measured for payment shall be the number of linear meters of new structure placed for the size and type of culvert that is completed and approved by the Engineer. This quantity shall be measured as the actual placed length of concrete pipe of a specified diameter, including all joints.

(b) Concrete pipe culvert inlets and outlets measured for payment shall be the actual number of completed units of the size and type in accordance with drawing requirements and approved by the Engineer.

9.1.2 CONCRETE BOX CULVERTS

(a) Concrete box culvert quantities to be measured for payment shall be the number of linear meters of new structure placed for the size and type of culvert that is completed and accepted. This quantity shall be measured as the actual placed centerline length of box culvert including inlets and outlets.

(b) Only inlet and outlet structures indicated in the Bid Price Schedule shall be measured for payment as the actual number of completed units of the size and type in accordance with drawing requirements and approved by the Engineer. All other concrete box culvert inlets and outlets shall not be measured separately for payment but shall be included as part of the box culvert quantity.



9.1.3 CATCH BASINS

Catch Basins will be the numbers and type of catch basins with grates and frames completed, installed and approved including concrete, reinforcing steel and all incidentals necessary for the completed and accepted work.

9.1.4 MANHOLES

Manholes will be the numbers of manhole, with grates and frames completed and installed and approved including concrete, reinforcing steel, benching, ladder rungs and all incidentals necessary for the completed and accepted work.

9.2 PAYMENT

The quantities as determined above shall be paid for in accordance with applicable Unit Prices as indicated on the Bill of Quantities. Payment shall be full compensation for furnishing and placing all the material, including all labor, equipment and tools, and any incidentals necessary to complete the prescribed work, including all necessary cleaning as prescribed in this Specification Section. The unit price shall be all inclusive of all necessary work, materials and incidentals required to properly construct the culvert, pipe or other drainage structures in accordance with drawings and specification requirements including, but not necessary limited to all excavation and backfill, concrete, reinforcing steel, water stop and all necessary joint materials.

As applicable, bedding material shall be paid in accordance with provisions of Specification section 04500 “Porous Drainage and Backfill” or as Class G concrete in accordance with provisions of Specification section 06100 “Concrete and Concrete Structures”.


DIVISION 4 - DRAINAGE WORKS Mortared Rip-Rap - Section 04400

SECTION 04400 - MORTARED RIP-RAP

TABLE OF CONTENTS

1. GENERAL.................................................................................................................................................. 1

2. SHOP DRAWINGS ................................................................................................................................. 1

3. DIMENSIONAL TOLERANCES .......................................................................................................... 1

4. SUBMITTALS........................................................................................................................................... 1

5. WORK SCHEDULING ........................................................................................................................... 1

6. RECTIFYING UNSATISFACTORY OR FAILED WORK................................................................ 2

7. MAINTAINING ACCEPTED WORK.................................................................................................. 2

8. MATERIALS ............................................................................................................................................. 2

8.1 STONE .......................................................................................................................................................... 2

8.2 MORTAR....................................................................................................................................................... 2

8.2.1 PLACING ....................................................................................................................................................... 2


9.1 PREPARATION OF FOUNDATIONS................................................................................................................ 3

9.2 PREPARING STONE....................................................................................................................................... 3

9.3 PLACING STONE LINING ............................................................................................................................. 3

9.4 CONSTRUCTING MORTARED RIPRAP STRUCTURES .................................................................................... 3


10.1 MEASUREMENT............................................................................................................................................ 4

10.2 PAYMENT ..................................................................................................................................................... 4



SECTION 04400 - MORTARED RIP-RAP

1. GENERAL

This Specification section describes requirements and procedures for furnishing and placing riprap for bank protection, slope protection, and erosion control. All work constructed on prepared beds shall be in accordance with this Specification section and conform with the lines, grades, and dimensions shown on the drawings or otherwise directed by the Engineer.

2. SHOP DRAWINGS

The Contractor shall furnish Shop Drawings containing the construction details for mortared rip-rap indicated on the Drawings and as directed by the Engineer. Shop Drawings shall be submitted to the Engineer prior to the start of the construction of mortared rip-rap. Construction of mortared rip-rap shall begin only after approval of Shop Drawings by the Engineer.

3. DIMENSIONAL TOLERANCES

(a) The surface of each face stone shall not vary from the average profile of the surrounding rip-rap by more than 3 cm.

(b) The average surface profile for waterway lining formed by placed rip-rap shall not vary from the specified or approved channel invert profile by more than 2 cm.

(c) The minimum thickness of any mortared rip-rap lining shall be 10 cm.

(d) The finished profiles for minor, non-load bearing structures such as catch pits and spillway aprons shall not vary from the specified or approved profiles by more than 2 cm.

4. SUBMITTALS

The Contractor shall submit to the Engineer two representative 50-kg stone samples before using any stone material in mortared riprap. The Engineer will retain one of these samples for reference throughout the Contract Period. The Contractor shall only use stone for the works that the Engineer approves.

5. WORK SCHEDULING

(a) The Contractor shall limit the extent of mortared riprap he carries out at any time to ensure that all stones are placed only in fresh mortar.



(b) Where mortared riprap paving is to be constructed on slopes or as roadside drain lining, the Contractor shall first form the slopes as if there were to be no paving. The Contractor shall shape the work to the final lines only immediately before placing the riprap.

6. RECTIFYING UNSATISFACTORY OR FAILED WORK

(a) The Contractor shall rectify at his own expense all mortared riprap which does not meet the tolerances given in this Specification section or as directed by the Engineer.

(b) The Contractor shall be responsible for the stability and integrity of all finished work. The Contractor shall replace at his own expense any damaged or displaced portions due (in the opinion of the Engineer) to the Contractor’s carelessness or neglect.

7. MAINTAINING ACCEPTED WORK

The Contractor shall be responsible for routine maintenance of all completed and accepted mortared rip-rap throughout the Contract Period. No separate measurement or payment shall be made for such routine maintenance.

8. MATERIALS

8.1 STONE

(a) Stones shall consist of angular fieldstone or rough-hewn quarry stone that is sound, tough, durable, dense, resistant to the action of air and water, and suitable in all respects for the purpose intended.

(b) The Engineer shall approve the quality and dimensions of the stones prior to use. Stones for paving roadside drains shall be as nearly rectangular in shape as practicable.

(c) Stones ranging from a minimum of 30 kg to a maximum of 70 kg with at least 50 percent of the stones weighing more than 50 kg shall be used.

8.2 MORTAR

Mortar shall be portland cement mortar in accordance with provisions and requirements of Specification section 08010 “Cement Mortar”.

8.2.1 PLACING

Surfaces to receive mortar shall be cleaned of oil, clay or other contaminants and thoroughly saturated before the mortar is applied. Free surface water shall be removed, however, before application of the mortar.




9.1 PREPARATION OF FOUNDATIONS

The Contractor shall prepare foundations in accordance with the provisions of Specification section 03400 “Embankment Construction”.

9.2 PREPARING STONE

(a) The Contractor shall clean the stones of all defects that may impair their bond with the mortar.

(b) The Contractor shall thoroughly wet the stones long enough for the stones to absorb water to near saturation state, prior to laying.

9.3 PLACING STONE LINING

(a) The Contractor shall place a bedding of fresh mortar at least 3 cm thick on prepared formations. The Contractor shall construct this mortar bedding progressively by laying the surface stones in such a manner that the stones are always securely bedded in the mortar before it hardens.

(b) The Contractor shall place the stones firmly against each other to provide the required paving thickness measured perpendicular to the slope. The Contractor shall then place additional mortar to fill all spaces between the stones completely. The finish shall be almost flush with the surface of the lining but the mortar shall not cover the stones.

(c) The work shall progress from the bottom of the slopes towards the top. The Contractor shall finish the surface immediately following the initial set of the mortar by sweeping the surface with a stiff broom.

(d) The Contractor shall cure the finished surfaces as specified for concrete work in Specification section 06100 “Concrete and Concrete Structures”.

(e) The Contractor shall trim and finish adjacent slopes and shoulders to ensure a tight and smooth interface with the mortared riprap. The interfaces shall allow unobstructed drainage and prevent scour at the edges of the work.

9.4 CONSTRUCTING MORTARED RIPRAP STRUCTURES

(a) The Contractor shall construct cut-off walls by filling the trench or forms with mortar to a depth of 60% of the maximum dimension of the stones. The Contractor shall then place the stones in the unset mortar immediately. The Contractor shall add additional mortar and repeat the process until the form is filled. The Contractor shall then add mortar to the top of the cut-off until he obtains a screeded level top surface.



(b) The Contractor may construct mortared riprap structures without forms if the stone can interlock sufficiently and if he uses stiff mortar.

(c) The Contractor shall finish and cure exposed surfaces of mortared riprap structures as specified in Specification section 06100 “Concrete and Concrete Structures”.

(d) The Contractor shall backfill around the finished and cured stone masonry structures in accordance with the provisions of Specification 03400, “Embankment Construction”.


10.1 MEASUREMENT

(a) Mortared Stone shall be measured for payment in cubic meters of the nominal volume of completed and accepted work. The nominal volume is defined as the product of area of exposed surface of the finished work and the nominal thickness of paving.

(b) For payment purposes, the nominal paving thickness shall be the specified or approved thickness shown on the Drawings or as directed by the Engineer,

(c) Any materials placed in excess of the approved theoretical volume shall not be measured for payment.

(d) Excavation for roadside drains lined with mortared rip-rap shall be measured and in accordance with Specification section 03100 “Common Excavation”.

10.2 PAYMENT

The quantities of Mortared Riprap, measured in accordance with the above noted requirements, shall be paid for in accordance with applicable Unit Price indicated on the Bill of Quantities. Payment shall be full compensation for supplying, transporting, and placing all materials for mortared riprap including:

(a) all necessary labor and equipment;

(b) forming and preparing foundations;

(c) constructing weep holes;

(d) dewatering works;

(e) backfilling and compaction;



(f) finishing; and

(g) all other works necessary or usual for completing mortared rip-rap described in this Specification section.


Unit

D-04400-1 Mortared Rip-Rap m3


DIVISION 4 - DRAINAGE WORKS Porous Drainage and Backfill - Section 04500

SECTION 04500 - POROUS DRAINAGE AND BACKFILL

TABLE OF CONTENTS

1. GENERAL.................................................................................................................................................. 1

2. DIMENSIONAL TOLERANCES .......................................................................................................... 1

3. REFERENCE STANDARDS .................................................................................................................. 2

4. SUBMITTALS........................................................................................................................................... 2

4.1 WORK SCHEDULING.................................................................................................................................... 2

5. MATERIALS ............................................................................................................................................. 3

5.1 POROUS BACKFILL OR FILTER MATERIAL ................................................................................................... 3

5.2 BEDDING MATERIAL FOR PIPES AND CONCRETE DRAINS.......................................................................... 4

5.3 PLASTIC FILTER MESH ................................................................................................................................. 4

5.4 POROUS PIPES AND WEEP HOLE PIPES ....................................................................................................... 4

5.5 MORTAR....................................................................................................................................................... 5

6. CONSTRUCTION REQUIREMENTS ................................................................................................. 5

6.1 PLACING POROUS BACKFILL....................................................................................................................... 5

6.2 PLACING BEDDING MATERIAL.................................................................................................................... 6

6.3 PLACING PLASTIC FILTER MESH ................................................................................................................. 6

6.4 PLACING POROUS PIPES .............................................................................................................................. 6

6.5 CONSTRUCTING WEEP HOLES .................................................................................................................... 7


7.1 MEASUREMENT............................................................................................................................................ 7

7.1.1 MEASURING POROUS BACKFILL OR FILTER MATERIAL ................................................................................ 7

7.1.2 MEASUREMENT OF PLASTIC FILTER MESH ................................................................................................... 8

7.1.3 MEASUREMENT OF POROUS PIPE .................................................................................................................. 8



7.1.4 WEEP HOLES, TARRED PAPER, AND CEMENT MORTAR ................................................................................8

7.1.5 EXCAVATION FOR POROUS BACKFILL, FILTER MATERIAL, OR SUBSURFACE DRAINAGE WORKS.................8

7.2 PAYMENT .....................................................................................................................................................8

Rehabilitation of Kabul-Dushi Highway, Afghanistan 02/04/03 04500 - ii


SECTION 04500 - POROUS DRAINAGE AND BACKFILL

1. GENERAL

This Specification addresses provision for supplying, transporting, placing and compacting porous backfill materials at locations as shown in the drawings or as directed by the Engineer and as required for

(a) the bedding of concrete drains or pipes,

(b) subsurface drainage purposes,

(c) preventing the washout or scour of soil fines by groundwater seepage,

(d) subsurface drains’,

(e) concrete lined drains,

(f) culverts and

(g) sand blankets.

Also included the supply, transport, and placing of porous pipes (drain tiles) and soil filter fabrics where these materials are shown on the Drawings or as directed by the Engineer.

2. DIMENSIONAL TOLERANCES

(a) Finished profiles for porous drainage granular fill shall not vary from the specified or approved profiles by more than 1 cm.

(b) Finished levels and grades for pipe and concrete drain bedding material shall not vary from those specified or approved by more than 1 cm.

(c) Dimensional tolerances for the shape, diameter, length and wall thickness of porous pipes shall be as specified in AASHTO M 179. The maximum gap between the ends of butt jointed porous pipes shall be 5 mm when laid.

(d) The minimum fall in drains constructed using porous pipe shall be 0.5% or as approved by the Engineer.

(e) Foundation surfaces for porous backfill used in drainage blankets shall be smooth and regular. The surfaces shall have a uniform fall that will prevent ponding. The minimum grade for such surfaces shall be 0.5%.




The most recent printing of the following AASHTO Tests shall apply to materials covered in this Specification section.

(a) T 27 Sieve Analysis of Fine and Coarse Aggregate;

(b) T88 Particle Size Analysis of Soils;

(c) T89 Determining the Liquid Limit of Soils;

(d) T90 Determining the Plastic Limit and Plasticity Index of Soils;

(e) T99 Moisture Density Relations of Soils Using a 2.5 kg Rammer and a 305 mm Drop;

(f) T191 Density of soil In-place by the Sand cone Method;

(g) T179 Clay Drain Tiles.

4. SUBMITTALS

(a) The Contractor shall submit representative samples of materials he intends to use at least 21 days prior to the proposed date of placing any materials.

(b) The Contractor shall submit at least one 50-kg sample of porous backfill or filter material for every 500m3 he proposes to use.

(c) The Contractor shall submit samples of porous pipe or filter mesh he proposes to use together with the manufacturer’s specifications and proof-test data

(d) The Contractor shall notify the Engineer in writing when he has completed placing the porous backfill and before it is concealed by any other work. The notification shall include the results of density tests specified as well as survey records verifying that his work meets the dimensional tolerances.

4.1 WORK SCHEDULING

(a) The Contractor may place clean granular porous drainage material only immediately prior to placing overlaying materials.

(b) The Contractor shall only place granular porous drainage material in horizontal layers at the same time as laying other embankment fill layers.



5. MATERIALS

5.1 POROUS BACKFILL OR FILTER MATERIAL

(a) Granular porous backfill or filter material shall be hard, durable and clean. It shall be free of organic material, clay balls, and other undesirable substances. The Contractor shall not use laterite or adhesive materials.

(b) The required particle grading of the material will depend on:

♦ its intended function in the works;

♦ on the characteristics of the materials that will be upstream and downstream of water seeping through it; and

♦ on the materials available.

The Engineer will direct the grading required for each case. The Engineer’s assessment shall include ensuring that piping (washing out of fine materials) cannot occur from the upstream material into the porous backfill or from the porous backfill into the downstream material in accordance with the following criteria.

(a) ( )( ) 5

85

15 <soilDfilterD

(b) ( )( ) 204

15

15 <<soilDfilterD

(c) ( )( ) 25

50

50 <soilDfilterD

where D15, D50 and D85 are the particle sizes from the grading curve at 15%, 50%, and 85% respectively, by weight. The term filter refers to the coarser protecting material. The term soil refers to the finer material being protected from piping.

Grading envelopes for typical porous backfill and filter materials which would carry seepage water without piping from typical embankment clay to 30 cm diameter rip-rap will be placed as directed by the Engineer.

In cases where there are weep holes or pipe perforations and no granular material downstream of the porous backfill, selection and approval of the porous backfill shall be based on the following criteria:

(a) D85 (backfill) > 0.2D (hole)

(b) D50 (backfill ) > 0.04D (hole)



Where D85 and D50 are defined as above; and D (hole) is the inside diameter of the weep hole or pipe perforation.

5.2 BEDDING MATERIAL FOR PIPES AND CONCRETE DRAINS

Granular bedding material may be sand, sandy gravel, or crushed stone. It shall conform with the requirements contained in Table No. 1.

TABLE NO. 1

Granular Bedding Material Requirements

Maximum Particle Size

(AASHTO T 88)

20 mm or less, but at least twice the maximum clear gap in any unmortared pipe joint

Passing No. 200 Sieve

(AASHTO T 88)

15% maximum

Plasticity Index

(AASHTO T 90)

6 maximum

Liquid Limit 25 maximum

5.3 PLASTIC FILTER MESH

Plastic filter mesh shall be a propriety woven synthetic geotextile fabric approved by the Engineer. The Contractor shall select the most suitable mesh opening size (MOS) for filter fabric based on the particle size distribution curve for the soil upstream of the filter fabric in accordance with whichever is the smaller:

♦ MOS < 5 D85 (soil)

♦ MOS < 25D50 (soil).

D85 and D50 are defined above in this Specification section.

5.4 POROUS PIPES AND WEEP HOLE PIPES

Porous pipes for subsurface drainage shall be clay drain tiles of approximately 100 mm inside diameter and meeting the requirements specified in AASHTO M 179 unless otherwise indicated on the Drawings.

Pipes to be placed through either concrete, mortared walls, or linings as well as those used as weep holes shall have a 50 mm inside diameter. The pipes may be made from any material approved by the Engineer which is strong enough to resist being deformed during construction and setting of the mortar or concrete.



5.5 MORTAR

Mortar used for locking pipe joints shall be Portland cement mortar in accordance with Specification section 08010 “Cement Mortar”.

6. CONSTRUCTION REQUIREMENTS

6.1 PLACING POROUS BACKFILL

(a) The Contractor shall replace all unsuitable material as directed by the Engineer before placing porous backfill on any area in accordance with this Specification section.

(b) The Contractor shall place porous backfill around pipes and drains or behind structures systematically and as soon as possible after placing the pipes or structure. The Contractor should, however, allow at least 14 days, or as directed by the Engineer, after mortaring the pipe joints or placing the structures before backfilling.

(c) The Contractor shall compact the porous backfill in layers not exceeding 15 cm to a density in excess of 100% of the maximum dry density determined according to AASHTO T 99. The Contractor may use any approved method of compaction which achieves the required density.

(d) The Contractor shall monitor the adequacy of compaction by taking density tests in accordance with AASHTO T191. If the tests show insufficient density has been obtained, the Contractor shall continue compaction or remedy the works as directed by the Engineer. The Engineer shall determine the frequency and location of the testing.

(e) The Contractor shall only nominally compact the first layer of earth fill on top of the thin drainage blankets (less than 20 cm thick) of porous backfill which are to be backfilled. The Contractor shall then compact the earth fill layer until the underlying layer of porous backfill has attained the specified density.

(f) The Contractor shall protect the porous drainage material from disturbances caused by traffic, animals, or pedestrians until other materials cover the material. The Contractor may lay temporary wooden planks over sand blankets to allow workmen to pass. The Contractor shall spread the first layer of fill over the porous material carefully and by hand so the two materials do not mix.

(g) The Contractor shall take care to ensure no mixing between the porous backfill material with the adjacent soil or fill. Where the Engineer believes this is occurring, the Contractor shall use a form to separate the two materials during placing. The form shall be 3 mm thick steel sheet or a



similar form acceptable to the Engineer. The Contractor shall lift the form gradually as the backfilling proceeds. The Contractor shall remove the form from the completed fill.

6.2 PLACING BEDDING MATERIAL

(a) The Contractor shall excavate trenches or foundation pits for pipe culverts, concrete drains, subsurface drains or other works requiring a bedding layer in accordance with requirements of Specification 03200 “Structural Excavation” The Contractor shall form a firm and uniformly compacted bed to the required grade less the thickness of the bedding material.

(b) The thickness of the pipe bedding shall not be less than 10% of the diameter of the pipe nor less than 5 cm for any works.

(c) The Contractor shall shape pipe bedding using a semi-circular template having the same outside diameter as the outside of the pipe so that the bedding provides uniform support. Where the Drawings call for a bell and spigot pipes, the dug recess shall accommodate the bells.

6.3 PLACING PLASTIC FILTER MESH

The Contractor shall install plastic filter mesh in accordance with the procedures the manufacturer recommends and as directed by the Engineer.

6.4 PLACING POROUS PIPES

(a) The Contractor shall prepare beds for porous pipes as described in sub-section 6.1 above and use porous backfill as specified in this Specification section

(b) The Contractor shall place porous pipes on the prepared bed and carefully position the pipes to the required alignment and grade. The pipes shall be but jointed with a 1 mm to 5 mm gap between the pipes. The Contractor shall wrap the joints with an approved filter fabric which will allow water to pass but not permit the porous backfill to pass. The Contractor shall further protect the upper half of each joint with a strip of tarred paper or a similar non-perishable sheet material. The Contractor shall lock in place, but not seal, each joint using a small amount of cement mortar on each side of the joint.

(c) The Contractor shall place backfill material over the laid pipes and compact it as specified under sub-section 6.1, after the Engineer inspects and approves the laid pipes.



6.5 CONSTRUCTING WEEP HOLES

(a) Where temporary weep holes are required through a wall or other structure, the method of forming the weep holes shall be as directed by the Engineer.

(b) The Contractor shall remove all non-durable forms after completing the structure.

(c) The weep holes shall have a minimum fall to the outside of 5% unless otherwise directed by the Engineer.

(d) The Contractor shall brace pipes that will function as weep holes in concrete structures while placing concrete.

(e) The Contractor shall space weep holes no greater than 2 meters horizontally and 1 meter vertically unless otherwise directed by the Engineer.

(f) Where weep holes require filter pockets, the filter material shall extend into the bedding or backfill at least 300 mm from the end of the hole in all directions unless otherwise directed by the Engineer.


7.1 MEASUREMENT

7.1.1 MEASURING POROUS BACKFILL OR FILTER MATERIAL

Fill shall only be classified and measured as porous backfill or filter material:

(a) when used in locations where porous backfill, filter material of filter pockets, or drainage blankets have been specified;

(b) where directed in writing by the Engineer; or

(c) when the material has been accepted by the Engineer as suitable as porous drainage.

The quantity of porous backfill measured for payment shall be the number of cubic meters of the compacted material required to fill the specified or approved lines. Any material the Contractor places in excess of the approved theoretical volume shall be regarded as either Embankment or Structure Backfill, as directed by the Engineer. Embankment or Structure Backfill shall not be measured under this Specification section irrespective of its material qualities.



7.1.2 MEASUREMENT OF PLASTIC FILTER MESH

The quantity of plastic filter mesh to be measured for payment shall be the number of square meters of approved fabric actually installed in the works and accepted in place.

7.1.3 MEASUREMENT OF POROUS PIPE

The quantify of porous pipe to be measured for payment shall be the number of linear meters of approved pipe at the specified diameter actually installed in the works and accepted in place. No deduction in the measured length will be made for the gaps at the pipe joints.

7.1.4 WEEP HOLES, TARRED PAPER, AND CEMENT MORTAR

Pipe used for forming weep holes, tarred paper, or other sheeting used to wrap joints and the cement mortar used to lock the pipe joints will not be measured for payment. The cost of these materials shall be included in the Unit Price for porous pipe.

7.1.5 EXCAVATION FOR POROUS BACKFILL, FILTER MATERIAL, OR SUBSURFACE DRAINAGE WORKS

No separate measurement for payment will be made for excavation or backfill. The cost of excavation and backfill shall be deemed incidental to carrying out the porous backfill, filter material, or subsurface drainage works.

7.2 PAYMENT

The work measured for Porous Backfill or Filter Material shall be paid for in accordance with applicable Unit Prices as indicated on the Bill of Quantities. Payment shall be full compensation for all labor, equipment, tools, materials, and incidentals necessary for completing the work as described in this Specification section and approved by the Engineer.

Pay Item

Description Unit of Measurement

D-04500-1 Porous Backfill or Filter Material m3

D-04500-2 Bedding Material for Pipes and Concrete Drains

m3

D-04500-3 Plastic Filter Mesh m2

D-04500-4 Porous Pipe lm


section 03500 - unsuitable material

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