0 sc&s9 piling work.pdf

8/10/2019 0 SC&S9 Piling Work.pdf

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SECTION 1 PILING WORK

1.1 GENERAL

The Contractor shall be wholly responsible for the stability of the piling and shall take every precaution

to prevent deflection or movement of driven piles and shall provide any temporary works necessary tomaintain all piling in its proper position until permanently secured in the works.

All piling works shall be executed in accordance with the drawings, this Specification and all currentCodes of Practice of Vietnam but not limited to TCXD190:1996 and TCXDVN 286:2003.

The Contractor shall be solely responsible for all arrangements and supply of all necessary labours,materials and everything necessary to complete the Work within the stipulated Contract Period.

In either case, the Contractor shall maintain records and perform all tests as the Engineer may deemnecessary for ensuring compliance with various provisions of this Specification.

The piling system shall comply with the relevant authority approval and permission in the site.

1.2 SOIL INVESTIGATION

The Contractor shall be solely responsible for obtaining all information on the nature of the site and sub-surface soil conditions for the purpose of preparing the tender and the subsequent execution of theContract.

Where the soil investigation borelogs are supplied to the Contractor, they shall be deemed to have been provided solely for his convenience and rough guidance only and not meant to form the basis oftendering. The provision of such data shall in no way relieve the Contractor of his responsibilities underthe Contract.

The Contractor may, at his own expense, conduct soil investigation at the site provided he has obtainedthe Engineer's prior written approval. The Contractor shall provide, free of charge to the Employer, twocopies of the results of all such soil investigation conducted.

1.3 DATUM AND REFERENCE PEGS

Unless otherwise specified, all chart datum shall be defined in relation to the National datum withreference to specified location.

The Contractor shall be responsible for safeguarding the position and levels of all survey pegs and benchmarks used for the setting out of the Works.

1.4 SETTING OUT AND GROUND LEVELS

The Contractor shall be responsible for establishing and locating all lines, levels and positions of all piles.He shall engage a Qualified (also refer to Liciensed or Registered) Surveyor recognized by the authorityfor the above work. The Contractor shall submit for approval two copies of setting out plan dulyendorsed by the Qualified Surveyor before the commencement of piling work. The Contractor shall

provide all necessary equipment, tools, labour and assistance required by the Engineer for the checkingof the setting out of each pile. The acceptance of the final position of each pile shall not relieve theContractor of his responsibility of all remedial works required as a result of inaccuracies in the positionsof piles installed.

Existing ground levels at pile positions shall be determined and agreed between the Contractor and theEngineer before piling works start. The ground levels so determined and agreed upon shall be used as a

basis for the determination of the pay length of the piles.

1.5 SCOPE OF PILING WORKS AND VALUATION

The Contract requires the supply of all materials, labour, plant, tools and everything necessary for the


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execution of piling works for the superstructure. Unless otherwise specified in the Contract, thefollowing valuation applies:

1) Provisional quantities are indicated in the Tender

2) The Piling item of the Lump Sum Tender Price shall be computed based on these quantities.

3) The difference in the final value of work completed as computed and the total tendered amount forPiling Works shall be treated as a variation calculated based on the same tendered rate per metre runfor piles and the same tendered rate per unit for joint, if applicable.

4) Unless otherwise specified, all load tests, except those failed or abandoned, conducted shall be paidat the rate as specified in the Schedule of Rates. The rate shall include provision of Reaction system,all labour, plant and equipment to carry out the test as specified.

1.6 TYPE OF PILING

All piles types shall be of high strength precast reinforced concrete unless otherwise specified in thedrawings.

Design working load, P design , Minimum allowable load, P min and maximum load, P max for RC pile is statedin the structural drawing general notes.

1.7 DESIGN AND MANUFACTURE OF PILES

The Contractor shall submit with his tender, all pile details, calculations and shop drawings, prepared bya professional engineer, for the Engineers approval.

Piles shall be manufactured on the site or by an approved manufacturer. Concrete for the piles shall beof grade specified in accordance to the Drawings unless otherwise approved by the Engineer with aminimum Portland cement content of 425 kg/m 3 and of low water cement ratio consistent with goodworkability and shall develop a minimum average strength of 33 N/mm 2 at 28 days (for works tests) and43 N/mm 2 at 28 days (for preliminary tests). Piles shall have been cast for at least 28 days before driving

and shall be continuously cured, for 10 days after casting by water supply to ensure continuouslyapplication of curing water. This supply must be connected before the casting of piles may commence.

Concrete tests shall be identical as specified in section 3.5. The Contractor will make the cubes underthe supervision of the Engineer.

Concrete, formwork and reinforcement for the piles shall comply with the relevant clauses of Section 3 -Reinforced Concrete Specification.

All piles shall be clearly marked with the date of which they were cast.

1.8 CASTING AND CURING

Piles are to be cast on site where directed by the Engineer, or alternatively purchased from a sourceapproved of by the Engineer who reserves the right to inspect the manufacture of the piles and to requesttest cubes of the concrete therein. Should any such cube test indicate that the purchased pile does notconform to the requirements of this Specification, the Engineer may order the entire consignment to beremoved from the site, and if the test failure is repeated, the source of piles is to be charged, or theContractor is to revert to site casting.

The Contractor is to supply sufficient moulds and cast piles in the most expeditious manner. TheEngineer may order additional moulds to be prepared, should he consider that the number of mouldssupplied are insufficient for the general progress of the work.

Concreting of each pile is to be completed in one continuous operation.

Main reinforcement bars are to be in complete lengths.

Piles are to have mild steel shoes, as approved of by the Engineer.


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1.9 HANDLING OF PILES

The Contractor shall ensure that the handling, stacking, pitching and driving are carried out in such a

manner that no damage to the pile occurs. Should any damage occur at any stage to any pile, it shall bereplaced entirely at the expense of the Contractor.

1.10 EQUIPMENT AND PLANT

The Contractor is to provide all frames, equipment, lifting and driving devices, including maintenanceand supply of fuel, with other plant, and labour necessary for the driving of piles.

Before the commencement of piling, the Contractor is to submit to the Engineer full details of hisworking programme, including the number and type of frames and hammers or rams which he intends touse, and the Engineer reserves the right to order the Contractor, at no additional cost to the Owner, to

provide any further plant which he, the Engineer considers necessary for the carrying out of the works.

The Contractor will also supply the Engineer with a full description of the proposed driving crews andinspectors. The Engineer may order the removal or replacement of any equipment or staff whenever heconsiders that such equipment and/or staff are not suitable for the works.

The Contractor will not remove any of his equipment or plant from the site until the Engineer hascertified in writing that all the piling, pile testing and other ancillary works have been satisfactorilycompletely.

The Contractor shall provide piling plant suitable for handling and driving the longest and heaviest pileexpected. Hammers shall be sufficiently heavy to drive all piles to a driving resistance of at least 2.5times the safe working load as calculated by the Hiley Formula.

1.11 PILE DRIVING AND INSTALLATION

All pile installations shall be carried out in the presence of the Engineer. Checking and measurement of plumb, alignment, rake, set and temporary compression shall be made as and when necessary or asdirected by the Engineer and in the presence of him or his representative.

Each pile shall be driven to final set as specified in the general notes.

The Engineer may order driving to continue, if he is not satisfied with the penetration or set obtained.

Driving shall be continuous process and no stoppage shall be made during driving of a complete pilelength other than for the extension of the pile, if required.

During taking set of piles, the driving must continuous. Changing of packings to be avoided wherever possible. Where packings are required to be changed, extra driving is necessary to compress the packings prior to taking sets.

Piles shall not be installed unnecessarily beyond the depths required for them to develop the requiredload carrying capacity. The Contractor shall state sound and acceptable basis for determining the

penetration required for all the piles. No payment shall be made for extra penetration or bored lengthwhich the Contractor cannot technically justify or which are not directed by the Engineer.

The Contractor shall take all necessary action to protect the works from the weather and suspend alloperations when it is raining or when the site condition is detrimental to the works and as directed.

Piles shall be maintained in their correct positions by means of guides or other approved methods but no pile which has been deflected from its course during driving or wrongly aligned shall be brought forcibly back to the correct alignment. During driving any pile deviating beyond the limits specified in thegeneral notes and to such an extent that the resulting eccentricity cannot be taken care of by a redesign of


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the pile cap or the pile ties shall, at the discretion of the Engineer, be replaced or supplemented by one ormore additional piles.

When the final set is being measured, the following requirements shall be met:

a The exposed part of the pile shall be in good condition without damage ordistortion.

b The dolly and packing, if any, shall be in sound condition.

1.12 PROTECTION TO PILE HEADS

Piles shall be protected by a suitable helmets and packings approved by the Engineer.

Followers or dollies shall be used only with the written permission of the Engineer.

1.13 PILE LENGTHS

The anticipated average driven length of each pile is expected to be approximately as shown on the piling plan. However, the Owner and the Engineer accept no responsibility if piles are found to be ofdifferent lengths or vary in length in a random manner. The Contractor will be deemed to have includedin his rates for any such variation in lengths, as may be necessary.

1.14 EXTENSION TO PILES

Piles shall general be fabricated in two sections. The bottom section shall generally be approximately12.00m long to suit the standard lengths of the longitudinal reinforcing bars. The top section shall be ofsuch lengths as may be required with a minimum section of 6m. Sections shall be joined by weldingtogether the junction plates cast into the ends of each pile.

1.15 POSITIONING OF PILES

Piles shall be driven accurately to the position indicated on the drawings. Any pile found to be out of position by an amount greater than 75mm at the pile cut off level or more than 1:75 from the vertical orform the required rake, whichever is applicable, such a pile shall be deemed to be defective.

For piles driven in groups exceeding two piles group, the resulting grouped eccentricity of piles shall notexceed 50mm.

The Contractor shall produce calculations prepared by the Professional Engineer for the Engineers

approval if the eccentricity exceeds the allowable tolerance.

Particular care shall be taken to ensure that the pile frame is vertical or at the required rake, duringdriving.

1.16 REPLACEMENT OF DEFECTIVE PILES

Any pile cracked, deformed, twisted or otherwise damaged in any manner, or not installed within thespecified tolerance shall be rejected at the discretion of the Engineer and replaced with substitute piles orsupplemented by additional piles by the Contractor at his expense. The position and number of substitute

pile or additional piles shall be decided by the Engineer to ensure that the concentricity of the pile group

is not altered.

The Employer will only pay the cost for the original number of pile/s in the pile group as shown on theDrawings. In the computation for payment, the size and penetration of the substitute pile shall be taken.If two or more piles are used to replace the rejected pile, the computation shall be based on the size and


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penetration of the substitute pile which has the deepest penetration.

In addition, the Contractor shall bear the extra costs and time occasioned by such rejection due toincreased size of pile caps, strengthening of the beams, etc. Costs shall be assessed at Contract rates ifthe remedial work is to be carried out by others. No extension of time to the contract period shall beentertained.

1.17 OBSTRUCTIONS

The piling rates shall include the use of all tools or equipment necessary for clearance of obstructionssuch as boulders, hard soil intrusions, tree stumps and other obstructions encountered for the first 3m

below existing ground level beyond which clearance of obstructions shall be based on rates in the Billsof Quantities.

No standing time for rigs will be allowed in consequence of obstructions.

1.18 REDRIVING

All piles risen as a result of ground upheaval shall be redriven to the required set or level at theContractors expense.

The Engineer may also require the Contractor to redrive certain piles not as a result of upheaval. In thiscase, the Contractor shall be paid according to a unit price included in the Bill of Quantities or byAgreement.

1.19 CUT-OFF LEVEL AND STRIPPING PILES

Piles shall be cut-off and strip to the levels as indicated on the drawings. This work shall be carried outlater during the subsequent contract work. The Contractor shall liaise and co-ordinate with othercontractor to ensure that the works are carried out expeditiously.

All debris and cut-off piles shall be removed from the site.

1.20 PAY LENGTH FOR PILES

The pay length for piles shall be measured from the driven toe level to cut off level, as shown on thedrawing.

1.21 LOAD TESTING

The Contractor shall submit Load test method statements with calculations on supports and anchors.Load tests shall be carried out on piles selected by the Engineer, at the time required by the Engineer incompliance to TCXDVN 269:2002.

Load testing of piles are preferred to be carried out after all piles have been driven. However, shouldload testings need to be carried out during pile driving, such testings shall be carried out at no extra costand time.

The Contractor shall notify the Engineer to witness calibration of pile test equipments (i.e. jacks, pressure gauges etc.). The Engineer shall keep the pressure gauge after calibration until the gauge isinstalled for testing on site.

1.22 FAILURE OF PILE UNDER TEST LOAD

Failuer criteria shall comply to TCXDVN269:2002.On completion of any test, the Contractor shall supply to the Engineer load/settlement/time graphs.


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The Engineer may require the Contractor to modify subsequent piles and to carry out further pile test(s)at the Contractors expense until a satisfactory result is achieved.

Should the Contractor continue to install piles pending the result of a pile, he shall do so at his own risk.The Engineer may require any pile so installed and represented by a pile which has failed under testloading, to be replaced or additional piles installed entirely at the Contractors own expense.

1.23 RECORDS

The Contractor shall keep a record of each pile installed and shall furnish signed copies to the Engineer'srepresentative daily.

The method of obtaining the required information and the format of records shall be in standard formatsas approved by the Engineer. The record shall include the following information:

a Set

b Temporary compression

c Pile penetration from ground level

d Length of pile and size of section

e Ground level

f Cut-off level to the top of pile

g Starting time and completion time

h Number of joints used

Once the driving of pile commences, it shall continue until final penetration or set is reached.

As and when required, the Engineer may ask for additional information or modify the standard formats.Such forms shall be provided by the Contractor before the commencement of piling work at his expense.

1.24 PILING SYSTEM AND DESIGN OF PILES BY CONTRACTOR

Unless otherwise specified, the Contractor may propose the use of piles patented or otherwise, differentfrom those designed by the Engineer. In exceptional case, depending on the nature of the site and thetype of work involved, two or more types of piles may, subject to the approval of the Engineer, be usedin the same project. Within the same group of piles under a column only one size and one type of pile is

permitted. It shall be the Contractor's responsibility to provide calculations and evidence to satisfy theEngineer of the suitability or adequacy of any system or combination of systems proposed. The decisionof the Engineer whether or not to accept the system proposed shall be final.

If the Contractor chooses to execute the piling work according to his own design, he shall state so in histender submission. He shall submit with his tender a comprehensive description of the proposed pilingsystem with the following drawings and information:

a Pile layout plans including the size, the number and the layout of the piles required to carrythe superstructure loads.

b Full details of design assumptions including negative skin friction (NSF) where necessary.

c Pile cap sizes and pile cut-off levels.

d Specification for materials, workmanship, pile driving criteria and procedure.

e Detail of pile shoe and joint splicing.

Pile layout proposed shall ensure complete safety and stability of structures. Column loading plans whichshow all the sizes and loading on each column, issued by the Engineer shall be used in preparing the pilelayouts. Each pile layout drawing shall contain the proposed cut-off of every pile.


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All drawings, information, qualifications or special conditions submitted with the tender shall form partof the Contract, provided that these do not in any way prejudice or vitiate any part of the Specification orConditions contained in the Engineer's Standard Specification for Civil/ Structural Works. Any extra costrequired to modify the structures, pile caps, tie-beams or defects, dispute, etc, resulting from the pilingsystem submitted by the Contractor shall be borne by the Contractor including design, administrative andsupervision cost.

The Contractor's design and specification shall comply with Vietnamese standards and this Specification,unless he has reasons acceptable to the Engineer for departing therefrom. The minimum factor of safetyagainst failure shall not be less than 3. In addition, the settlement of the pile under full test load forworking load test shall not exceed the maximum value allowed in the Code of Practice. It shall be hisresponsibility to itemize and refer each and every departure from the Code or this Specification to theEngineer for consideration and written approval before implementing the work. In matters notspecifically covered by the Code and this Specification, the Contractor's proposals shall be in accordancewith accepted principles of good foundation engineering practice and shall also be subject to theEngineer's approval.

In the event that the piling system proposed by the Contractor is acceptable, the Contractor shall obtain aProfessional/Qualified Engineer's endorsement on his proposal before final acceptance.

Failure to comply with the above may render the tender to be rejected.

If at any stage during the progress of work, it is found that the Contractor has failed to comply with the provisions of this Clause, such works as completed shall be liable for rejection without any payment tothe Contractor.

1.25 BAKAU (or CU TRAM) PILES

1.25.1 General

All Bakau shall also refer to C Tr m for the entire 9.25 Section.

Where Bakau piling is included in the tender, the Contractor shall allow for and provide everythingnecessary for the proper execution of bakau piling. Any difference in quantities of piling works betweenthose shown on the Drawings and/or specifications and those executed on site shall be adjusted byVariation Orders which shall be paid in accordance with the Schedule of Rates. In the event that no

bakau piling is required, the entire cost for piling where shown on the Drawings or inferred therefromshall be deducted from the Contract Sum based on the Schedule of Rates.

1.25.2 Bakau or Cu Tram Piles

Bakau / Cu Tram piles shall be of approved species, good, straight and reasonably uniform in size. The

mean between the maximum and minimum diameters of the piles including the bark, measured at thelarger end, shall not be less than 80mm and pile diameters shall not be measured over knots and

protuberances. All piles shall be sufficiently straight along their axis so that a line drawn between thecentres of both ends will be wholly within the pile. Piles shall be supplied in any of the two lengths asinstructed by the Engineer -not exceeding 2.2m and exceeding 2.2m but not exceeding 4.4m measuredafter the pile heads have been squared and the ends pointed. For depth of penetration not exceeding 4.4m,no joint will be allowed for the piles and for depth of penetration exceeding 4.4m but not exceeding 8.8m,only one single joint will be allowed. Unless otherwise shown, the Contractor is deemed to have allowedin the tender for the cost of one joint for each pile with the depth of penetration exceeding 4.4m but notexceeding 8.8m.

All piles shall be inspected and approved by the Engineer before being used. Piles that have beenrejected shall be removed from the site immediately.

1.25.3 Pile Driving


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Piles shall be driven by experienced operators. Driving of piles shall be by approved means, accurately inthe correct locations, free from deviation of any kind, in accordance with the Engineer's instructions. A

piling frame or tripod with a free drop hammer of approved weight and not less than 200 kg shall be usedto drive piles to a final set of 250mm for the last ten blows from a drop of 1.5m. Piles may be required to

be piled to refusal, if necessary. Pile heads shall be protected with a simple steel helmet during drivingand after completion of piling, the heads shall be properly squared and cut off to the required levels.

In the installation of piles where joints are not required, the Contractor may propose other methods of pile installation subject to Engineer's approval. However, the piles so installed shall have a carryingcapacity equal or greater than piles installed by piling frame method as described above.

Should the pile heads be cut to a level below the specified level, the Contractor shall be required to fill upat his own expense the difference with concrete of such proportions or with such materials as theEngineer shall direct.

The bakau piles that are to be piled along precast cantilever drain slab units must be aligned exactly towhere the units are to be sited.

1.25.4 Test Piles

The Contractor shall provide and drive test piles when and where directed by the Engineer to determineground conditions or the length of piles required.

1.25.5 Defective Piling

Incorrectly or badly driven piles and piles damaged during driving shall be extracted or replaced or elseduplicated all at the Contractor's own expense.

1.25.6 Pile Jointing

All piles shall be rigidly and securely joined with steel collars of 300mm long made out of No 18 gaugemild steel sheets with joints fully welded. Steel collars shall be completely coated with tar or bituminous

paint.

1.25.7 Heaved Piles

Any driven pile which has been lifted from its original seat due to driving of adjacent piles or soilheaving shall be re-driven to resistance as specified under Pile Driving .

1.25.8 Piling Record

Piles shall only be driven in the presence of the Engineer or his representative and the penetrations andsets of every pile shall be subjected to his approval. For each pile the Engineer's representative and theContractor shall record down the original length, set, penetration and cut-off level measured from groundlevel and the number of joints.

1.25.9 Removal Of Obstructions

Sub-clause Obstructions shall be applicable to bakau piling.

1.25.10 Load Testing

Due to ground disturbances or poor piling conditions, the Contractor may be required to carry out simpleload tests to determine the soundness of the piles, in accordance with the instructions of the Engineer.


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1.26 DYNAMIC PILE TESTING

1.26.1 General

The contract includes static load tests, low strain integrity and high strain dynamic pile tests. The lowstrain test required is the low strain sonic test or equivalent. The high strain test is the dynamic stressmeasurement under a driving hammer impact.

The Contractor shall engage an independent specialist firm, with qualified testing license in Vietnam, instress wave measurement to carry out the dynamic pile monitoring. The specialist firm shall haveextensive experience in stress wave measurement and a proven record in such works. The engineeroperator for such works shall have at least 3 years experience in field monitoring and analysis withadequate qualifications.

Prior to testing, the Contractor shall submit to the Engineer for approval the name of the specialist firm, adetailed method of testing criteria and parameter used in testing including the preparation of the pile head,setting up of the hammer for inducing the required impact energy, a list of equipment and operator he

proposes to use for the testing.

All load tests shall be carried out as the Engineer may direct and under the supervision of an experiencedand competent Supervisor who shall be conversant with the test equipment and test procedures.

The Contractor shall take all necessary precautions to safeguard his workmen against any hazards thatare involved in the testing or preparation for the testing of piles.

When the dynamic pile test fails to meet with the specified requirement, a static load test shall be carriedout to confirm the failure. The result of the static load test shall form the basis for the rejection of theworking pile.

The static load test performed on piles that failed to meet the requirements shall be borne by theContractor and no claim for extra cost and time shall be granted for carrying out the static load test.

1.26.2 Method Of Testing To Be Approved

The Contractor shall submit to the Engineer for approval a description, accompanied by drawings, ofmethod(s) he proposes for providing the necessary reaction and required force for compression tests, forsupporting the fixed datum bar and for complying with the requirements of the Engineer. The proposalshall be signed by a Professional/Qualified Engineer registered in the Singapore, Malaysia or Vietnam.

Notwithstanding any approval of the Contractors proposal by the Engineer, the Contractor shall be fullyresponsible for the successful execution of load tests and all consequences arising thereof.

1.26.3 Low Strain Integrity Testing

Piles for low strain integrity shall be determined by the Engineer.

The preparation of pile head for integrity testing shall be carried out, in accordance with the testingspecialists recommendations, by the Contractor all at the Contractors own cost.

The testing equipment shall consist of a highly sensitive accelerometer and special purpose powersupply/amplifier-receiver, a small impact device and a personal computer with digitizing and graphiccapability.

The accelerometer shall be attached to the pile top and acceleration and velocity records shall be takenunder an impact of the device.The signal from the accelerometer shall be processed to check for pile toe and pile shaft continuities. Thetesting method shall separate effects of impact and surface reflections from other relevant reflections byaveraging records of several impacts.

The equipment shall have exponential amplification of the signal with time.


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Any abnormal test record shall be analysed using computer stress wave equation analysis to obtain aquantitative assessment of pile defects.

The report shall include field plots and analysis. Interpretation of each record for the piles tested and anystress wave analysis carried out. Any defects indicated shall include the nature, location and severity ofthe defect.

1.26.4 High Strain Dynamic Pile Testing

High strain dynamic pile testing shall be carried out using a Pile Driving Analyser (PDA), associatedtransducers and recording equipment. Selected data collected shall be analysed by CAPWAP(PDI)computer stress wave analysis or equivalent as approved by the Engineer.

Prior to testing, the Contractor shall submit to the Engineer for approval, the proposed driving systemand the driving criteria. The proposed system and driving criteria shall be justified using stress wave

procedure or equivalent method.

Pile integrity and estimate of the bearing capacity shall be evaluated based on the procedure developed atthe Case Western Reserve University, Ohio, USA, or other approved equivalent procedure.

The Contractor shall install two sets of strain transducers and accelerometers near to the top of each pileto be tested, and shall make available the necessary measuring and recording system such as the PileDriving Analyzer, tape recorder and oscilloscope. The Contractor shall analyse the results of eachmeasurements and provide the Engineer with the following information for each pile subjected to stresswave measurements:

-CASE static capacity estimate-Energy transmitted to the pile-Compression force magnitude-Tension force magnitude-Acceleration and velocity maxima-Pile integrity

The Contractor shall make provision and access to the pile determined by the Engineer to restrike testing.Such testing shall be carried out at time periods sufficiently long after the end of initial driving to allow

pore water pressure and soil strength changes to occur. In cases where the pile has been driven too closeto the ground level this may require excavation around the pile head or pile extension to an exposedsection of at least three pile diameters below the pile head.

The Contractor shall take set-rebound measurements during testing. For drop hammers and single actingand steam hammers, the drop of ram or ram travel and number of blows shall be recorded.

All stress wave measurements shall be made in the presence of the Engineer or his authorisedrepresentative.

For the piles tested, the Engineer may select any records of the filed measurement to be analysed usingCAPWAP stress wave analysis or equivalent approved method. The results of the analysis shall includethe static resistance, driving system performance and assessment of integrity of the pile; and shall also

provide separate end bearing, skin friction component of the pile capacity and produce a load settlementcurve.

On completion of the field measurements, the Contractor shall submit a final report covering all aspectsof pile monitoring and analysis work. The report shall incorporate results of the field estimates, results ofthe computer analysis and any correlations drawn between the dynamic test results and the geologicalinformation, and static load tests if applicable. The report shall furnish the qualification of the technical

personnel responsible in this testing work, calibration of equipments and sensors, testing agency licensein Vietnam.

1.26.5 Removal Of Temporary Works

On completion of all pile testing, all temporary works shall be removed and temporary piles extracted or,if approved by the Engineer, cut-off at bed level or at such depth below ground seabed level as the


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Engineer may direct, all at the Contractors own cost.

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