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2/6/2014 SUMMER INTERNSHIP REPORT CONSTRUCTION OF UNDERPASSED AND FLYOVERS ALONG DARSAIT- AL WADI AL KABIR ROAD Muscat, Oman

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Page 1: L&T Oman 2

2/6/2014

SUMMER INTERNSHIP REPORT

CONSTRUCTION OF UNDERPASSED AND

FLYOVERS ALONG DARSAIT- AL WADI AL KABIR ROAD

Muscat, Oman

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SUBMITTED BY: Sagnik Bhattacharjee

3rd Year Undergraduate Student

I.D. Number: 110411094

Department of Civil Engineering

Indian Institute of Engineering Science and Technology, Shibpur

(Formarly known as Bengal Engineering and Science University

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Table of Contents

ACKNOWLEDGEMENT ........................................................................ 1

INTRODUCTION.................................................................................. 2

PROJECT DETAILS ............................................................................... 5

STRUCTURE-WISE PROGRESS ............................................................. 7

BRIDGE CONSTRUCTION ................................................................... 42

MATERIALS AND QUALITY TESTING LABORATORY ............................ 46

PROJECT EXECUTION ........................................................................ 78

HIGHWAY CONSTRUCTION ............................................................... 92

CONCLUSION ................................................................................... 97

REFERENCE ...................................................................................... 98

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CI_RD_107_01_07_001.dgn 5/28/2012 11:08:50 AM

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My summer internship with Larsen and Toubro (Oman) LLC. has been a

wonderful learning experience and will be of great benefit for my professional

career as a civil engineer. This internship gave me an insight of how the execution

of civil engineering practice takes place on a construction site and has given me a

lot of practical knowledge and skills which will be of great for my career.

I wish to express my gratitude to LARSEN & TOUBRO (OMAN) LLC. for giving

me this special opportunity to undertake my summer internship at the “Design &

Construction of Underpassed and Flyovers along Darsait – Al Wadi Al Kabir

Road” as this project involved many unique construction practices and challenges.

It also gave me the unique exposure of construction practices employed in the

Sultanate of Oman for bridges and highways.

I wholeheartedly offer my gratitude to Mr. K. M. Mahadev, Project Manager of

Design & Construction of Underpass and Flyovers along Darsait – Al Wadi Al

Kabir Road for his invaluable support and guidance in bringing this summer

training to new dimension. I would also like to thank all the staff of Larsen and

Toubro (Oman) LLC. for being so helpful during the summer training.

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INTRODUCTION

Larsen & Toubro Limited, also known as L&T, is an

Indian multinational company headquartered in Mumbai, India. It was founded in 1934 by

Danish engineers taking refuge in India, as well as an Indian financing partner. The company has

business interests in engineering, construction, manufacturing goods, information technology and

financial services, and also has an office in the Middle East and other parts of Asia. L&T is

India's largest engineering and construction company.

Larsen & Toubro (Oman) L.L.C. is a branch of the mother company Larsen & Toubro Limited

which is operating in Oman. It provides engineering, construction and contracting services. It

supplies construction products. The company was founded in 1994 and is based in Muscat,

Oman. Larsen & Toubro (Oman) L.L.C. operates as a subsidiary of Larsen & Toubro Ltd. The

company is a joint venture between Larsen & Toubro Ltd, India’s leading engineering and

construction company, and The Zubair Corporation. It’s specialization covers innovative, cost-

effective construction techniques and total project management skills for vital sectors such as

cement, power, petrochemical, refineries.

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INTRODUCTION

L&T (Oman) has achieved a major breakthrough in the urban infrastructure segment

internationally by bagging twin orders valued at Riyal Omani 68.4 million (approx. 875

crore) from the Muscat Municipality and from the Ministry of Transport & Communication,

Sultanate of Oman. The orders are for construction of the Al Wadi Al Kabir– Darsait Road.

The Wadikabir – Darsait Road project is scheduled to be completed in 24 months. It involves

design and construction of flyovers and underpasses along the Darsait – Al Wadi Al Kabir

Road. Set to meet the highest international standards, these projects are expected to

significantly streamline traffic.

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The orders were won by L&T Oman against stiff international competition and auger well for

L&T’s expansion plans in the urban infrastructure space in rapidly growing international

markets. L&T has been making significant strides in the area of roads and bridges both in the

international and domestic markets through its well-established capabilities in design,

engineering, project execution and construction, quality and safety standards and on-time

delivery.

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PROJECT DETAILS

PROJECT DETAILS

PROJECT Design & Construction of

Underpass and Flyovers

along Darsait – Al Wadi Al

Kabir Road

EMPLOYER Head of Muscat Municipality

Diwan of Royal Court,

Sultanate of Oman

SUPERVISION

CONSULTANT

Renardet & Partners

Consulting Engineers L.L.C.

DESIGN CONSULTANT Parsons International &

Company LLC

CONTRACTOR Larsen & Toubro (Oman)

LLT

LETTER OF AWARD 20th September 2011

DATE OF CONTRCT

AGREEMENT

9th January 2012

CONTRACT VALUE RO 42,268,093

CONTACT NUMBER DGB/045/11

CONTRACT DURATION 761 days

CONTRACTUAL

COMPLETION

21st October 2013

EXPECTED COMPLETION 31st March 2015

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Figure 1(Topographical Map of the Al Wadi Al Kabir- Darsait Road

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STRUCTURE-WISE PROGRESS This section will display the structure wise progress of the construction of the underpasses and

flyovers along the Al Wadi Al Kabir- Darsait Road. This will be shown by the pictures below in

the following order:

Al Wadi Al Kabir Round About

Sheraton Underpass

Star Cinema

Matrah Flyover

Darsait Wadi Bridge

Darsait Underpass

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AL WADI AL KABIR ROUND ABOUT

8 Cell Culvert in Progress

Abutment 2- SB & NB completed. Backfilling in Progress

Pier 8- NB & SB Waterproofing & Backfilling Completed

Pier 7- NB & SB Waterproofing & Backfilling Completed

Pier 6- NB Pier Completed, SB Rebar and Shutter in Progress

SB Retaining Wall Completed

NB Retaining Wall in Progress

ROP Boundary Wall Construction in Progress

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Picture 1 [8 Cell Culvert in Progress]

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Picture 2 [Abutment 2- SB & NB completed. Backfilling in Progress]

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Picture 3 [Pier 8- NB & SB Waterproofing & Backfilling Completed]

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Picture 4 [Pier 7- NB & SB Waterproofing & Backfilling Completed]

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Picture 5 [Pier 6- NB Pier Completed, SB Rebar and Shutter in Progress ]

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Picture 6 [SB Retaining Wall Completed]

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Picture 7 [NB Retaining Wall in Progress ]

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Picture 8 [ROP Boundary Wall Construction in Progress ]

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SHERATON UNDERPASS

Pipe Jacking in Progress

Excavation for Utility Laying in Progress

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Picture 9 [Pipe Jacking in Progress ]

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Picture 10 [Excavation for Utility Laying in Progress ]

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STAR CINEMA

Utility diversion pipe jacking works in progress infront of Star Cinema

Pipe Laying works in progress near Star cinema

New boundary wall Omantel (steel railing installation/plastering) works in progress

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Picture 11 [Utility diversion pipe jacking works in progress infront of Star Cinema]

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Picture 12 [Pipe Laying works in progress near Star cinema]

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Picture 13 [New boundary wall Omantel (steel railing installation/plastering) works in progress]

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MATRAH FLYOVER

SpanA1-P1 & P1-P2 Staging Completed

Span P1-P2 Girder Shutter in Progress

Pier Waterproofing & Backfilling Completed

Retaining Wall Staging and Rebar in Progress

Abutment 2- abutment wall retaining wall unit 8 reinforcement works in progress

Abutment 2- retaining wall unit 8 reinforcement works in progress

Abutment 2- retaining wall unit 10,11, 12 PCC works in completed

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Picture 14 [SpanA1-P1 & P1-P2 Staging Completed ]

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Picture 15 [Span P1-P2 Girder Shutter in Progress ]

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Picture 16 [Pier Waterproofing & Backfilling Completed]

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Picture 17 [Retaining Wall Staging and Rebar in Progress]

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Picture 18 [Abutment 2- abutment wall retaining wall unit 8 reinforcement works in progress]

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Picture 19 [Abutment 2- retaining wall unit 8 reinforcement works in progress]

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Picture 20 [Abutment 2- retaining wall unit 10,11, 12 PCC works in completed]

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DARSAIT WADI BRIDGE

PIER-1 PIER-2 PIER-3 PIER-4 PIER-5 PIER-6

Abutment-1 Abutment-2

PIER-1 PIER-2 PIER-3 PIER-4 PIER-5 PIER-6 PIER-7

Abutment-2

Bait Al Falaj - Wadi Bridge

WEST BOUND

EAST BOUND

Abutment-1Abutment-2

Abutment-1

Staging CompletedBeam Soffit Clear

StagingCompletedBeam Soffit Clear

Staging CompletedBeam Soffit Clear

Girder Pre Casting in Progress

WB P3-P4 Cast in Situ Girder in Progress

LHS Retaining Wall- Waterproofing & Backfilling in Progress

LHS Retaining Wall- Unit 1 A & 1B in Progress

RHS –Retaining Wall in Progress

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Picture 21 [Girder Pre Casting in Progress]

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Picture 22 [WB P3-P4 Cast in Situ Girder in Progress]

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Picture 23 [LHS Retaining Wall- Waterproofing & Backfilling in Progress]

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Picture 24 [LHS Retaining Wall- Unit 1 A & 1B in Progress]

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Picture 25 [RHS –Retaining Wall in Progress]

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DARSAIT UNDERPASS

Bait Al Falaj Underpass

A-1 A-2

Abutment-1 Abutment-2

Abutment 1 wall concreting completed

Abutment 2 retaining wall concreting completed

Abutment 1 retaining wall unit 2 shuttering works in progress

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Picture 26 [Abutment 1 wall concreting completed]

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Picture 27 [Abutment 2 retaining wall concreting completed]

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Picture 28 [Abutment 1 retaining wall unit 2 shuttering works in progress]

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BRIDGE CONSTRUCTION For the bridge that is to be constructed across the Al Burj Street interchange, there are 9 spams in

total. Each span is 35000 mm long. For the making of a span, there are three stages.

1. Soffit

2. Web Wall

3. Deck Slab

Soffit refers to the placement of reinforcement bars across the span profile. It is done after

diaphragm bars are placed above the diaphragm which is placed at the top of bearings above the

pier caps at the bottom of the spam at each end. Inside the spam, a hollow gap is maintained to

reduce the dead load of the spam.

For erecting this hollow gap, web walls are to be erected after Soffit. For this web wall

reinforcement bars are placed over the Soffit. Due to grouting, leakage occurs. Web walls here

also play the role of bridge girder. After web walls, shuttering and concreting is done. Then the

deck slab is placed on the top of the hollow gaps. The deck slab is also called concrete blanks or

infill slap.

PIERS There are 8 piers. On top of piers, pier caps are kept and then the bearing is kept. The diaphragm

is kept on top of that. Leveling of piers is done through total stationing as per design.

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SCRAPWORK For the formwork, the blue coloured H-frames are kept on concrete sleepers blocks to transfer its

load to the ground. The H-frames height vary from different heights. They are adjustable. These

frames are called DOKA Basic Frames and they vary with 1.8 m, 1.2 m and 0.9 m height. On top

of the H-frame, H20 DOKA bars are used and then RMD material is kept in grid from.

First the concrete plate is kept on top of it. The spindle jack is fixed on the concrete sleeper using

the base plate. Finally the H-frames are attached. On top of the H-frames, soldiers are placed.

The soldiers hold the profile angle, which are curved using supporting jacks. Then, Leveling of

piers is done through total stationing as per design. Plywood of 18mm depth is placed over the

inner straight part of the profile. For the curved sides of the profile 6 mm plywood is kept in 3

layers. The spindle jack is attached the base plate using a supreme lock. Spindle jack is also

called Towers Pandal. The DOKA Steel Weller is used to hold the H frames together. They are 6

meters long. They are attached to the H frame using a shivel couple

POST STRESSING Within the web walls, the duct pipes are placed for placing the post stressed wires within.After,

post stressed wire are kept, grouting is done. Theoritical modulus of elasticity is 195000 MPa.

The actual value varies from 190000MPa to 200000MPa. Speciment length used for testing

purpose is 500 mm.

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Postressing withing a spam of a bridge is done by using a decoiler and a threading machine

(Spinge SP/02). From the decoiler, the post stressing wires are pushed into the duct pipe after

rolling it into the threading machine. The stressing of the steel rods inside the duct pipe is done

using hydraulic machines. After 7 days, the pressure and the jacking force of the post stressing

steel wires are calculated. Finally, grouting within the duct pipe is done.

GROUTING Grout is poured into the duct pipe to hold the post stress wires together in the duct pipe and fill

the space between the duct pipe walls and the wires. Pressure is applied to remove all the air

voids out of the pipe. Grout is prepared by mixing the following materials

Cement (Ordinary Portland Cement- Grade 43)

Admixture (BASE Meyco Flow Cable and Fosroc Cebex Cable)

Water

Ice

After mixing the above 4 materials using a stirrer, it is poured into duct pipe from the inlet

through pipes. Pressure is applied using a hydraulic pump to push the grout. Mixing time is 5

minutes and the temperature to be maintained for chilled water is 5 degrees. There are a few tests

which are conducted with the grout before mixing.

Temperature Test: The temperature of the grout is measured and recorder. The maximum

temperature of grout is 30 degrees.

Fluidity Test: This is the test used to determine the flow properties of grout. It is done by

using the Flow Cone apparatus. The apparatus comprises a metal stand supporting the

stainless steel cone having inside dimensions of 150 mm inside upper dia. and 280 mm

height.

Other Tests: These include:

Bleeding Test

Volumetric Expansion

Compressive Strength

Mix Proportion

The mix proportion of the grout is as followes:

Cement (100 kg)

Admixture (6 kg)

Water (36kg)

CONCRETING This is the stage where concrete is poured into the formwork and is allowed to settle over it

covering the reinforcements which are placed as per design. Before this is done, the concrete is

tested upon arrival from the batch plant. For the construction of the flyovers along the Al Wadi

Al Kabir- Darsait Road, the concrete is manufactured by Al Turki Cement Products LLC. It is

one of the leading suppliers of ready mix concrete in the construction industry in Muscat, Oman.

The concrete is brought to the site by trucks which can carry approximately 40 mm2 of concrete.

Once it is brought to the construction site, slump test and density test is conducted. . Before

pouring concrete, Nicobond is applied on the vertical sides of the construction joint between new

and old concrete. Once it is assured that the given concrete is as per the requirement of the

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flyover construction, it is poured into the formwork. For concreting of super-structure, C 45/20 is

used for deckslab and C 45/10 is used for box girder. The thickness of the deck slab is 200 mm.

For the sub-structure, C 40/20 is used. Pouring is done using Boom and Boom Placer as shown

in the picture below. After it is poured, it is leveled and kept for 7 to 28 days to gain full strength

as per the given chart.

Age Strength per

cent 1 day 16% 3 days 40% 7 days 65% 14 days 90% 28 days 99%

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MATERIAL AND QUALITY TESTING LABORATORY

There are three laboratories:

Geotechnical Testing Laboratory

Concrete Testing Laboratory

Asphalt Testing Laboratory

LIST OF EXPERIMENTS

Geotechnical Testing Laboratory

Atterberg’s Limit Test

Determination of Maximum Dry Density and Optimum Moisture Content

California Bearing Ratio Test

Los Angles Abrasion Test

Sand Equivalent Test

Concrete Testing Laboratory

Aggregate Crushing Value Test

Aggregate Impact Test

Penetration of Bitumen

Rapid Chloride Penetration Test

Compressive Strength Test

Water Permeability Test

Asphalt Testing Laboratory

Analysis of Compacted Bituminous Paving Mixture using Marshall Specimen

Determination of Thickness and Degree of Compaction of Compact Paving Mixture

Granular Sub-Base Sieve Analyses

Determination of Bitumen Content Using Extraction Method and Sieve Analyses

ATTERBURG’S LIMIT TEST

Objective

The objective of this experiment is to determine the plastic limit and the elastic limits of fine

grain soil to be used for the construction of the underpasses and flyovers along Darsait- Al Wadi

Al Kabir Road.

Principle

The plastic limit of a soil is the lowest water content at which a soil can no longer be deformed

by rolling into 3.2 mm diameter threads without crumbling. The plasticity index of a soil is the

range in water content, expressed as a percentage of the mass of the over-dried soil, within which

the material is in a plastic state. It is the numerical difference between the liquid limit and plastic

limit of the soil. The liquid limit of a soil is defined as the water content at which the behavior

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of a clayey soil changes from plastic to liquid. The importance of the liquid limit test is to

classify soils. Different soils have varying liquid limits. Also, one must use the plastic limit to

determine its plasticity index.

Apparatus

Liquid limit device

Porcelain dish

Flat grooving tool with gage

10 Moisture cans

Balance

Spatula

Drying Oven

Wash Bottle filled up with distilled water

Procedure

Liquid Limit:

1. First pass the given soil sample though a standard sieve as per ASTM D 4318. After air-

drying, and then pulverizing the soil sample, it is finally ready for testing. Take roughly

three-fourth of the soil and place it into the porcelain dish. Thoroughly mix the soil with a

small amount of distilled water until it appears as a smooth uniform paste. Cover the dish

with cellophane to prevent moisture from escaping.

2. Weigh 5 of the empty moisture cans with their lids, and record the respective weights and

can numbers on the data sheet.

3. Adjust the liquid limit apparatus by checking the height of drop of the cup. The point on

the cup that comes in contact with the base should rise to a height of 10 mm. Use the

block on the end of the grooving tool which is 10 mm high as a gage. Check whether the

cup drops approximately two times per second and determine the correct rate to rotate the

crank.

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4. Place a portion of the previously mixed soil into the cup of the liquid limit apparatus at

the point where the cup rests on the base. Squeeze the soil down to eliminate air pockets

and spread it into the cup to a depth of about 10 mm at its deepest point. The soil pat

should form an approximately horizontal surface.

5. Use the grooving tool carefully cut a clean straight groove down the center of the cup.

The tool should remain perpendicular to the surface of the cup as groove is being made.

Use extreme care to prevent sliding the soil relative to the surface of the cup

6. Make sure that the base of the apparatus below the cup and the underside of the cup is

clean of soil. Turn the crank of the apparatus at a rate of approximately two drops per

second and count the number of drops, it takes to make the two halves of the soil pat

come into contact at the bottom of the groove along a distance of 13 mm. If the number

of drops exceeds 50, then go directly to step eight and do not record the number of drops,

otherwise, record the number of drops on the data sheet.

7. Take a sample, using the spatula, from edge to edge of the soil pat. The sample should

include the soil on both sides of where the groove came into contact. Place the soil into a

moisture can cover it. Immediately weigh the moisture can containing the soil, record its

mass, remove the lid, and place the can into the oven. Leave the moisture can in the oven

for at least 16 hours. Place the soil remaining in the cup into the porcelain dish. Clean and

dry the cup on the apparatus and the grooving tool.

8. Remix the entire soil specimen in the porcelain dish. Add a small amount of distilled

water to increase the water content so that the number of drops required to close the

groove decrease.

9. Repeat steps six, seven, and eight for the next 4 trials producing successively lower

numbers of drops to close the groove. One of the trials shall be for a closure requiring 25

to 35 drops, one for closure between 20 and 30 drops, and one trial for a closure requiring

15 to 25 drops. Determine the water content from each trial by using the same method

used in the first laboratory. Remember to use the same balance for all weighing.

Plastic Limit

1. Weigh the remaining empty moisture cans with their lids, and record the respective

weights and can numbers on the data sheet.

2. Take the remaining one-fourth of the original soil sample and add distilled water until the

soil is at a consistency where it can be rolled without sticking to the hands.

3. Form the soil into an ellipsoidal mass. Roll the mass between the palm or the fingers and

the glass plate. Use sufficient pressure to roll the mass into a thread of uniform diameter

by using about 90 strokes per minute. (A stroke is one complete motion of the hand

forward and back to the starting position.) The thread shall be deformed so that its

diameter reaches 3.2 mm, taking no more than two minutes.

4. When the diameter of the thread reaches the correct diameter, break the thread into

several pieces. Knead and reform the pieces into ellipsoidal masses and re-roll them.

Continue this alternate rolling, gathering together, kneading and re-rolling until the thread

crumbles under the pressure required for rolling and can no longer be rolled into a 3.2

mm diameter thread.

5. Gather the portions of the crumbled thread together and place the soil into a moisture can,

then cover it. If the can does not contain at least 6 grams of soil, add soil to the can from

the next trial. Immediately weigh the moisture can containing the soil, record its mass,

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remove the lid, and place the can into the oven. Leave the moisture can in the oven for at

least 16 hours.

6. Repeat steps three, four, and five at least two more times. Determine the water content

from each trial by using the same method used in the first laboratory. Remember to use

the same balance for all weighing.

ATTERBERG LIMITS

Name of Project: Design & Construction of Underpasses and Flyovers along

Darsait- Al Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Sample

Description

Date of Sampling

Sampling Method BS 812 part 102 Date of testing

Source Test Method

Location Sample Number

Liquid Limit Plastic Limit

Test

Number

1 2 3 4 5 1 2 3 4 5

Number

of Blows

Container

Number

Container

+ Wet

Soil

Container

+ Dry

Soil

Weight

of Water

Weight

of

Container

Weight

of Dry

Soil

Moisture

Content

(%)

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Liquid Limit

Plastic Limit

Plasticity Limit

DETERMINATION OF MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE CONTENT

Objective

To determine the maximum dry density and optimum moisture content of the soil to be used for

the construction of the underpasses and flyovers along Darsait- Al Wadi Al Kabir Road and also

to find their relation.

Principle

This test covers the determination of the dry density of soil containing some coarse gravel when

it is compacted in a specified manner over a range of moisture contents. The range includes the

optimum moisture content at which the maximum dry density for this degree of compaction is

obtained. The test is suitable for soils containing no more than 30 % by mass of material retained

on the 20 mm test sieve, which may include some particles retained on the 37.5 mm test sieve.

Maximum density: The maximum density of a material for a specific compactive effort is the

highest density obtainable when the compaction is carried out on the material at varied moisture

contents.

Optimum moisture content: The optimum moisture content for a specific compactive effort is the

moisture content at which the maximum density is obtained.

The degree of compaction of soil is measured in terms of dry unit weight. During compaction,

water is added to the soil and acts as a lubricating agent on the soil particles. The soil particle slip

on each other and move into densely packed positions. For similar compacting efforts, the dry

unit weight will increase with the increase of moisture content. However, beyond a certain point,

additional moisture tends to reduce the dry unit weight because water takes spaces that might

have been occupied by solid particles. Figure 4.1 shows the general nature of the relation of dry

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unit weight to moisture content for a given soil and compacting effort. The moisture content at

which the maximum dry unit weight is obtained is called optimum moisture content.

For a given moisture content, the theoretical maximum dry unit weight is obtained when no air is

in the void spaces, i.e., degree of saturation = 100%. Thus, the maximum dry unit weight at a

given moisture content with zero air void (zav) is .

For 100% saturation, e = wGs;

Therefore

Where

γzav = dry unit weight at zero air voids

γw = unit weight of water

e = void ratio

w = moisture content

Gs = specific gravity of soil solids

Besides moisture content, the compaction characteristics of a soil generally depends on the soil

type and the compaction effort. In order to duplicate and control the quality of field compaction,

Proctor (1933) developed a laboratory dynamic compaction test method later called the standard

Proctor test (Das 1979).

Figure 2

Apparatus

Cylindrical metal mould (internal dimensions: 105mm diameter and 115.5mm high. This

gives a volume of 1000 cm3.The mould is fitted with a detachable base-plate and

removable extension collar)

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Metal rammer with 50mm diameter face, weighing 2.5kg, sliding freely in a tube which

controls the height of drop to 300mm.

Measuring cylinder 200 ml or 500 ml.

Caliper

Large metal tray, e.g. 600 x 600 x 60mm deep.

Balance, 10kg capacity reading to 1g.

Jacking apparatus for extracting compacted material from the mould.

Small tools: palette knife; steel straight-edge, 300mm long; scoop, cleaning brush, plastic

hammer, and general purpose trowel.

Equipment for moisture content determination

Procedure

1. Weigh the mould body without extension collar to the nearest 1g.

2. Check that the lugs or clamps hold the extension collar and base-plate securely to the

mould, and assemble them together. Check the rammer to ensure that it falls freely

through the correct height of drop, and that the lifting knob is secure.

3. Pass the dry sample weighing 4kg through 20mm British Standard sieve.

4. Mix the sample thoroughly with the amount of water as per Table 4.1.

Water (ml) Added Target M/C (%)

400 10

80 12

80 14

80 16

60 17.5

5. Place the mould assembly on a solid base. Add loose soil to the mould so that after

compaction the mould will be one-third filled.

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6. Compact the soil by applying 27 blows of the rammer dropping from the controlled

height of 300mm

7. Take care to see that the rammer is properly in place before releasing. The hand which

holds the tube must be kept well clear of the handle of the falling rammer. Do not attempt

to grab the lifting knob before the rammer has come to rest; a finger to thumb trapped

between knob and tube can sustain a nasty injury.

8. The first few blows of the rammer, which are applied to soil in a very loose state, should

be applied in a systematic manner to ensure the most efficient compaction and maximum

reproducibility of results. The sequence shown in should be followed for the first four

blows. By this means the effort dissipated in displacing loose material is kept to a

minimum. After that the rammer should be moved progressively around the edge of the

mould between successive blows, to a total No. of 27 blows so that the blows are

uniforming distributed over the whole area. Soil must not be allowed to collect inside the

tube of the rammer, because this will impede the free fall of the rammer.

9. The guide tube must be held vertically. Place the tube gently on the soil surface. If the

correct amount of soil has been used, the compacted surface should be at about one-third

of the height of the mould body. If the level differs significantly (by more than, say, 6

mm) from this, remove the soil, break it up, mix it with the remainder of the prepared

material and start this stage again.

10. Lightly scarify the surface of the compacted soil with the tip of a spatula or point of a

knife.

11. Place a second, approximately equal layer of soil in the mould, and compact with the

same numbers as before. Repeat with a third layer, which should then bring the

compacted surface in the extension collar to not more than 6mm above the level of the

mould body. If the soil level is higher than this, the result will be inaccurate, so the soil

should be removed, broken up and remixed, and the test repeated with slightly less soil in

each layer.

12. Remove the extension collar carefully. Cut away the excess soil and level off to the top of

the mould, checking with the straight-edge. Any small cavities resulting from removal of

stones at the surface should be filled with fine material, well pressed in.

13. Weigh soil and mould to the nearest 1g (m1) then remove the base-plate.

14. Fit the mould on to the extruder and jack out the soil. Break up the sample on the tray.

15. Take up representative samples in moisture content containers for measurement of

moisture content, using the standard procedure described in M/C determination test. This

must be done immediately, before the soil begins to dry out. The measurement is denoted

by w%.

16. Break up the material on the tray, and mix with the remainder of the prepared sample.

Add an increment of water as per Table 4.1. Mix in the water thoroughly.

17. Repeat stages 3 to 9 for each increment of water added, so that at least four compactions

are made. The range of moisture contents should be such that the optimum moisture

content (at which the dry density is maximum) is near the middle of that range. If

necessary to define the optimum value clearly, carry out one or more additional tests at

suitable moisture contents. Keep a running plot of dry density against moisture content so

as to see when the optimum condition has been passed.

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DETERMINATION OF MAXIMUM DRY DENSITY AND OPTIMUM

MOISTURE CONTENT OF SOIL

Name of Project: Design & Construction of Underpasses and Flyovers along

Darsait- Al Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Sample Description Date of Sampling

Sampling Method BS 812 part 102 Date of testing

Source Test Method

Location Sample Number

Weight of Mould A Volume of Mould B

Trial No.

Water Added

(%)

Mould + Wet

Soil

Weight of

Wet Soil

Wet Density

Container No.

Container +

Wet Soil

Container +

Dry Soil

Weigth of

Container

Weight of

Water

Weight of

Dry Soil

Moisture

Content

Dry Density

of Soil

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Maximum Dry Density (Mg/m

3)

Optimum Moisture Content (%)

Equipment Asset Number:

Remarks:

CALIFORNIA BEARING RATIO TEST

Objective

To determine the California Bearing Ratio of the soil to be used for the construction of the

underpasses and flyovers along Darsait- Al Wadi Al Kabir Road.

Principle

An indication of the state of compaction of a cohesionless (free-draining) soil is obtained by

relating its dry density to its maximum and minimum possible densities. There are 2 types of

testsTwo tests are described for the determination of maximum density, one for sands and one

for gravelly soils. In both tests the soil is compacted under water with a vibrating hammer. The

test on sands is carried out in a 1 L mould.

Apparatus

Molds (Cylindrical mold with an internal diameter of 6 in. and a height of 7 in. with an

extension collar of 2 in. height and a perforated base plate)

Spacer Disk (A circular disk of metal 5 – 15/16 in. diameter and 2.416 in. height)

Rammer (A rammer of mass 4.54 kg)

Apparatus for measuring expansions (This consists of a swell plate with adjustable stem

and a tripod support for a dial indicator)

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Surcharge weights (Several slotted or split metal plates of 149.2 mm; diameter and 5 lb

weight)

Penetration Piston (A metal Piston of circular cross – section having diameter of 1.954 in,

Area = 3in2 and not less than 4 inches in length)

Loaded Device (A compression type apparatus capable of applying a uniformly

increasing load up to 10,000 lb at a rate of 1.3 mm/min.Soaking Tank: A tank suitable for

maintaining the water level of 1 in, above the top of specimen)

Drying Oven (Oven Capable of maintaining a temperature of 110 + 5 0C for drying

samples)

Moisture content Containers

Miscellaneous (Tools such as mixing pans, spoons, straightedge, filter paper, balances

etc.)

Procedure

1. Approximately 18 kg soil pass of 19mm sieve and retain of sieve no. 4 is taken.

2. Moisture and dry density curve is obtained using the standard AASHTO T 99 or T 180.

3. Optimum Moisture Content (OPC) is obtained from the graph between moisture content

and dry density.

4. Prepare the sample by adding optimum moisture content and then compact the soil in five

layers by applying 10,30 and 65 blows respectively in three CBR molds using 10 lb

rammer having 18 in. height of fall. The compacted densities of the three specimens

range from 95 percent to 100 % of the maximum dry density already determined by the

T 180 compaction test.

5. Soaking: Place the swell plate with adjustable stem on the soil sample in the mold and

apply sufficient annular weights to produce an intensity of loading equal to the mass of

sub-base and base courses and surfacing above the tested material, but not less than 4.54

kg (10 lbs). Place the tripod with dial indicator on top of the mold and make an initial dial

reading.

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6. Immerse the mold in water to allow free access of water. Place the sample in water for 96

hours.

7. Make a dial reading on soaked specimen and calculate swell as a percentage of initial

sample height.

8. Remove the sample from tank and allow to drain for 15 minutes.

9. Penetration Test: Place the mold on the loading frame and adjust its potion until the

piston is centered on the specimen.

10. Seat the penetration piston with a 44 N (10 lb) load, and set both the load dial and the

strain dial to zero. This initial load is considered as the zero load when determining the

stress-penetration relationship.

11. Place the surcharge weights on the specimens equal to that used during soaking. Apply

load at a rate of 1.3 mm / min and record the load for penetration of 0.025 in, 0.05 in,

0.075 in, 0.10 in and so on up to 0.5 inches.

12. Stress strain curve: Plot curves between load and penetration for each specimen. Apply

the corrections to the curves if required. Take the readings of load for 0.1 in and 0.2 in.

penetration and find CBR for both penetrations. The greater values is the required CBR

for that specimen. Also find the dry density for each specimen.

13. CBR = Test load value, divided by, the standard load, multiplied by 100.

14. Design CBR: it is calculated by plotting a graph between CBR values and dry densities of

all the three specimens and then calculating the design CBR against value of 85 %

maximum dry density

LOS ANGLES ABRASION TEST

Objective

To determine the Los Angles abrasion value and to find the suitability of aggregates for use in

the construction of the underpasses and flyovers along Darsait- Al Wadi Al Kabir Road.

Theory

The Los Angeles test is a measure of degradation of mineral aggregates of standard gradings

resulting from a combination of actions including abrasion or attrition, impact, and grinding in a

rotating steel drum containing a specified number of steel spheres. The L.A. Abrasion test is

widely used as an indicator of the relative quality or competence of mineral aggregates.

The aggregate used in surface course of the highway pavements are subjected to wearing due to

movement of traffic. When vehicles move on the road, the soil particles present between the

pneumatic tyres and road surface cause abrasion of road aggregates. The steel reamed wheels of

animal driven vehicles also cause considerable abrasion of the road surface. Therefore, the road

aggregates should be hard enough to resist abrasion. Resistance to abrasion of aggregate is

determined in laboratory by Los Angeles test machine. The principle of Los Angeles abrasion

test is to produce abrasive action by use of standard steel balls which when mixed with

aggregates and rotated in a drum for specific number of revolutions also causes impact on

aggregates. The percentage wear of the aggregates due to rubbing with steel balls is determined

and is known as Los Angeles Abrasion Value.

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Apparatus

Los Angeles testing machine

Sieves

Balance – accurate within 0.1% of range required for test

Charge – the charge shall consist of steel spheres averaging approximately 46.8 mm in

diameter and each weighing between390 and 445 g. The charge, depending upon the

grading of the test sample, shall be as follows:

Grading Number of Spheres Weight of Charge, g

A 12 5000 +/- 25

B 11 4584 +/- 25

C 8 3330 +/- 20

D 6 2500 +/- 15

Procedure

1. Material Preparation: The test sample shall be washed and oven-dried (105 to 115 °C) to

substantially constant weight, separated into individual size fractions, and recombined to

the grading most nearly corresponding to the range of sizes in the aggregate as originally

furnished.

2. Wash the coarse aggregate test sample, per ASTM C136, and oven-dry (105 to 115 °C) to

substantially constant weight. Separate into individual size fractions, and recombine to

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the grading (Table 1) most nearly corresponding to the range of sizes in the aggregate as

originally furnished. The weight of the sample prior to test shall be recorded to the

nearest 1 g.

3. Place the test sample and the charge in the Los Angeles testing machine

4. Rotate the machine at a speed of 30 to 33 rpm for 500 revolutions.

5. Discharge the material from the L.A. abrasion machine and separate the sample on a

No. 12 sieve (1.70 mm).

6. Weigh the material coarser than the No. 12 sieve and record this as the final weight.

LOS ANGLES ABRASION TEST

Name of Project: Design & Construction of Underpasses and Flyovers along Darsait- Al

Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Sample Description Date of Sampling

Sampling Method Date of Testing

Source Test Method ASTM C131/ ASTM C 535

Location Sample Number

Mix Type

Grading Type

Number of Balls

Mass of Balls

Number of Revolution

Mass of Sample before Test

Mass of Sample after Test

Mass of sample retained on 1.7 mm sieve

Percentage Loss

Los Angles Abrasion Value (%)

Equipment Asset No.:

Specification Limits:

Remarks:

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SAND EQUIVALENT TEST

Objective

To determine the sand equivalent of granular material for use in the construction of the

underpasses and flyovers along Darsait- Al Wadi Al Kabir Road.

Theory

The purpose of this test method is to indicate, under standard conditions, the relative proportions

of clay-like or plastic fines and dusts in granular material and fine aggregates that pass the 5.00

mm sieve. A minimum sand equivalent value may be specified to limit the permissible quantity

of clay-like fines in an aggregate. The test may also be used for detemining changes in the

quality of aggregates during production or placement.

Apparatus

Graduated cylinder

Siphon assembly including a 4.5 L bottle fitted with a siphon, pinch cock and rubber

tubing, placed on a shelf 914 mm + 25 mm above the working surface.

Measuring tin approximately 57.0 mm in diameter and capacity of 85 + 5 ml.

Clock or watch reading in minutes and seconds.

Sieve 5.00 mm

Stove or hot plate

Miscellaneous supplies such as suitable pan, spatula, brush, trowel and rubber stopper to

fit the gradualted cylinder.

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Procedure

Equipment Preparation

1. Ensure that the graduated cylinder with weighted foot and irrigator tube are constructed

in accordance with Figure 206-5.

2. Ensure that the siphon assembly including the 4.5 L bottle fitted with a siphon, pinch

cock and rubber tubing is placed on a shelf 914 mm + 25 mm above the working surface.

Sample Preparation

1. Screen sample on the 5.00 sieve by hand sieving.

2. Materials retained on the sieve is dried on the stove at approximately 120 degrees and

rubbed between the hands. Then rescreened on the 5.00 mm sieve.

3. Combine the rescreened material with the original material and mix thoroughly.

Aggregates Sand Equivalent

Carefully obtain test sample by quartering the combined material passing the 5.00 mm

sieve. The test sample will consist of sufficient material to fill the measuring tin to a

slightly rounded level above the brim after tapping.

Test Procedure

1. Start siphon and add working solution to a depth of 100 mm in the graduated cylinder.

Pour sample into the cylinder and tap firmly to dislodge any air bubbles and aid in

wetting the sample.

2. Leave the wetted sample undisturbed for 10 minutes + 1 minute.

3. Shake the stoppered cylinder vigorously from side to side in a horizontal linear motion.

4. Agitation will consist of 90 cycles in about 30 seconds using a throw of approximately

230 mm + 25 mm and a cycle will consist of a complete back and forth motion. Set the

cylinder upright and remove the stopper.

5. Insert the irrigator tube and start the flow, rinsing the material from the cylinder walls as

the tube is lowered. Flush the fine material into suspension by gentle stabbing and

twisting of the irrigation tube to the bottom of the cylinder. Raise the irrigator tube slowly

and adjust the flow to the 381 mm level of the cylinder.

6. Allow the cylinder and contents to stand undisturbed for 20 minutes + 15 seconds.

7. Record the "clay reading" from the cylinder gradations and if the reading lies between

gradations record the higher gradation.

8. Lower the weighted foot in the cylinder until it comes to rest on the sand. Twist the rod

slightly until one of the centering screws can be seen.

9. Record the centre of the screw as the "sand reading" and if the reading lies between

gradations record the higher gradation.

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SAND EQUIVALENT TEST

NAME OF PROJECT Design & Construction of Underpasses and

Flyovers along Darsait- Al Wadi Al Kabir

Road

CLIENT Muscat Municipality

CONSULTANT Renardet SA & Partners Consulting Engineers

LLT

CONTRACTOR Larsen & Toubro (Oman) LLT

Sample Description Date of Sampleing

Sampling Method Date of Testing

Source Test Method ASTM D 2419

Location Sample Number

Mix Type

Testing 1 2 3

Sand Reading - A

Clay Reading - B

Sand Equivalent

Value (A/B)*100

Average Sand

Equivalent Value

Equipment Asset

Number

Specification Limits

Remarks

AGGREGATE CRUSHING VALUE TEST

Objective

To determine the aggregate crushing value of coarse aggregates which are to be used in the

construction of the underpasses and flyovers along Darsait- Al Wadi Al Kabir Road.

Apparatus Required

Open Ended Steel Cylinder (150mm nominal internal diameter, base plate and plunger)

A cylindrical metal (measure of 115mm + 1mm internal diameter and 180mm + 1mm

depth)

A Metal Tamping Rod circular (Cross section, 16mm + 1mm diameter. 600mm + 5mm

long with one rounded end)

A rubber mallet.

Electronic Balance (for weighing at least 30 kg to 0.1 grms and an Electronic Balance 30

kg to 1 grms)

BS Test Sieves 14.0mm, 10mm and 2.36mm

Compression Testing Machine ( 2000kn Crushing Machine)

Two 450mm clean square trays and a stiff bristle brush.

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Theory

The aggregate crushing value gives a relative measure of the resistance of an aggregate to

crushing under a gradually applied compressive load. Crushing value is a measure of the strength

of the aggregate. The aggregates should therefore have minimum crushing value.

Procedure

Preliminaries

1. A designated area will be used to perform this test and a clear area of bench must first be

allotted before this test proceeds.

2. All equipment to be used in this test must first be checked.

3. Check that the ACV mould, base plate and plunger are clean, smooth and undamaged and

that the calibration label is current.

4. Check that the measuring cylinders and rod are clean and in good order

5. Check that the Compression machine is set up ready for the test.

6. Check the sieves as required on receipt for damage to the mesh. If any excessive marks

and stretches, splits and dents are present, the sieves will be taken out of service.

Standard Test Method

1. The aggregate used in this test will have been obtained from a bulk sample that was

initially taken and prepared in the manner described in BS EN 932-1:1999. This must be

checked to ensure that the test portion is of standard size. If not, the non-standard test

procedure or sample preparation must be carried out in accordance with Appendix A of

the Standard. This involves either testing aggregate larger than 14mm in the standard

mould or for aggregates retained 2.36mm, the standard or modified smaller mould.

2. The aggregate to be tested must be in a surface dry condition. When the bulk sample is

fully saturated it will be dried to a surface dry condition by spreading the material on a

large tray and leaving on top of one of the drying ovens to air dry.

3. The bulk sample may then be passed through both the sieves retaining the portion passing

the 14mm and retained on the 10mm, every effort being made to recover all the material

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of this grade, though care should be taken not to further degrade the aggregate. Oversize

and undersize are rejected.

4. Slightly more than four times the amount that fills the metal measure should be obtained

for the crushing test, to give four test specimens.

5. The measure is filled in three layers rodding each layer 25 times with the tamping rod,

allowing the rod to fall from a height of approximately 50mm above each surface, and the

top leveled using the tamping road as a straight edge. The aggregate is now emptied into

a small tray and dried in an oven at 105+5 degrees for not more than 4 hours. The

material is allowed to cool and weighed. This is repeated for a further specimen. The

remaining two shall be retained for test if the repeatability of the first two results is

unacceptable.

6. Place the test cylinder on the clean base plate.

7. The aggregate will be added in three layers each being subjected to 25 strokes of the

tamping rod evenly distributed over the surface, dropping tamping rod from a height of

approximately 50mm above the aggregate surface.

8. The final surface will be carefully leveled off and the plunger place into the cylinder so

that it rests horizontally on the surface and is not trapped by the sides of the cylinder.

9. The apparatus will be placed between the platens of the compression testing machine and

the load of 400kN applied in 10 min + 30 seconds at as uniform rate as possible. The load

will be released and the apparatus removed from the compression machine.

10. Place a clean tray on the balance and zero the balance. The crushed aggregate will be

carefully removed from the cylinder over the tray by tapping the side of the cylinder with

a rubber mallet until the aggregate becomes loose and falls freely into the tray.

11. Any particles adhering to the surfaces of the cylinder, base plate or plunger will be

removed with a stiff brush and added to the aggregate in the tray. The weight of the

crushed material is recorded.

12. The whole of the aggregate will be hand sieved through the 2.36mm sieve until no

significant amount passes in 1 min.

13. The fraction passing the 2.36mm sieve will then be weighed to the nearest gram and the

weight recorded on the work test sheet as (Mass B). The fraction Retained on the 2.36mm

sieve is also weighed and recorded as Mass C.

14. Care will be taken to ensure that there is no loss of fines throughout these procedures. If

when the % Retained and % Passing the 2.36mm are added together, the combined

weight varies from the initial test weight by more than 10g, discard the result and start

again.

15. The procedure will then be repeated on the next sample.

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AGGREGATE CRUSHING VALUE

Name of Project: Design & Construction of Underpasses and Flyovers along Darsait- Al

Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Sample Description Sample Number

Source Date of Sampling

Location Date of Testing

Mix Type Test Method BS 812 Part 110

Sampling Method Load Applied (kN)

Aggregate Crushing Value

AGGREGATE IMPACT TEST

Objective

To determine the impact value of the road aggregates and to assess their suitability in

construction of the underpasses and flyovers along Darsait- Al Wadi Al Kabir Road on the basis

of impact value.

Apparatus

(As per British Standards)

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A testing machine (It is supported on level and plane concrete floor of minimum 45 cm

thickness. The machine should also have provisions for fixing its base)

A cylindrical steel cup

A metal hammer or tup (The hammer should slide freely between vertical guides and be

concentric with the cup. Free fall of hammer should be within 380±5 mm)

A cylindrical metal measure (for measuring aggregates)

Tamping (rounded at one end)

A balance (readable and accurate upto 0.1 g)

Theory

The property of a material to resist impact is known as toughness. Due to movement of vehicles

on the road the aggregates are subjected to impact resulting in their breaking down into smaller

pieces. The aggregates should therefore have sufficient toughness to resist their disintegration

due to impact. This characteristic is measured by impact value test. The aggregate impact value

is a measure of resistance to sudden impact or shock, which may differ from its resistance to

gradually applied compressive load.

Procedure

1. Aggregates may be dried by heating at 100-110° C for a period of 4 hours and cooled.

2. Sieve the material through the specified BS sieves. The aggregates passing through sieve

comprises the test material.

3. Pour the aggregates to fill about just 1/3 rd depth of measuring cylinder.

4. Compact the material by giving 25 gentle blows with the rounded end of the tamping rod.

5. Add two more layers in similar manner, so that cylinder is full.

6. Strike off the surplus aggregates.

7. Determine the net weight of the aggregates to the nearest gram(W).

8. Bring the impact machine to rest without wedging or packing up on the level plate, block

or floor, so that it is rigid and the hammer guide columns are vertical.

9. Fix the cup firmly in position on the base of machine and place whole of the test sample

in it and compact by giving 25 gentle strokes with tamping rod.

10. Raise the hammer until its lower face is 380 mm above the surface of aggregate sample in

the cup and allow it to fall freely on the aggregate sample. Give 15 such blows at an

interval of not less than one second between successive falls.

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11. Remove the crushed aggregate from the cup and sieve it through BS sieves until no

further significant amount passes in one minute. Weigh the fraction passing the sieve to

an accuracy of 1 gm. Also, weigh the fraction retained in the sieve.

12. Compute the aggregate impact value. The mean of two observations, rounded to nearest

whole number is reported as the Aggregate Impact Value.

Observations

Sample 1 Sample 2

Total weight of dry sample ( W1 gm)

Weight of portion passing 2.36 mm

sieve (W2 gm)

Aggregate Impact Value (percent) =

W2 / W1 X 100

Mean =

Result

Aggregate Impact Value =

Recommender Values

Classification of aggregates using Aggregate Impact Value is as given below:

Aggregate Impact Value Classification

<20% Exceptionally Strong

10 – 20% Strong

20-30% Satisfactory for road surfacing

>35% Weak for road surfacing

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RAPID CHLORIDE PENETRATION TEST

Objective

To assess the durability of concrete, specifically, the ingress of chloride into concrete which

is to be used in the construction of the underpasses and flyovers along Darsait- Al Wadi Al

Kabir Road

Theory

Concretes incorporating fly ash or silica fume are less permeable to deleterious elements

and thus are more durable than conventional concretes. The Rapid Chloride-ion

Permeability Test (RCPT) was designed to assess the resistance and durability of

concrete to the penetration of chloride ions, an indicator of its permeability. Chloride is

detrimental because it can accelerate the corrosion of reinforcing steel within concrete.

One way to prevent chloride ingress is to make the concrete less permeable, which is one

of the benefits of using fly ash. The rapid chloride permeability (RCP) does not measure

the migration of chlorides per se, but rather measures the conduction of an electrical

charge through concrete. The underlying principle is that concrete which resists the

passage of an electrical charge is less permeable and thus would also inhibit chloride

ingress. This inference is somewhat controversial, although a general relationship

between the RCP test results and actual chloride permeability data has been

demonstrated.

Apparatus

(This is a fully self-contained, complete kit as per ASTM C 1202-05 including the following

items)

Plexiglass chambers with brass mesh, terminals and Steel bolts - 3 Pairs

Nitobond EP Hardner

Nitobond EP Base

60V DC Constant voltage power supply with 3 channels – 01 No

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250 mm vacuum dessicator – 01 No

Vacuum pump – 01 No

Double Stage Moisture trap – 01 No

Electrometric Rubber Moulds for cylindrical specimens - 3 Nos.

Temperature probe – 01 No

Consumables - good for 1 doz. tests

RTV sealant + gun – 01 No

Acrylic sealer + brush - 01 No

Procedure

1. Prepare the sample for testig purpose by mixing Nitobond EP Hardner and Nitobond EP

Base and paint them in a core cutter of 15mm depth. This satge is called conditioning of

core cutting.

2. Put the prepared sample on air vaccume for 3 hours and then on water vaccume for 1

hour and after that keep the sample on soaking condition without any vaccume for 18

hours.

3. Attach the sample in contact with brass screens, which are attached to the inner

surface of the cells and wired to electrical contacts on the exterior of the cells.

One cell is filled with an NaCl solution, while the other is filled with an NaOH

solution.

4. Connect the electrical leads to the RCP analyzer, and pass an electrical current

from one cell, through the concrete section, and out the other cell.

5. The total charge passed in 6 hours is recorded as the test result. ASTM has

devised a very general permeability scale based on the charge passed.

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RAPID CHLORIDE PENETRATION TEST Project Design & Construction of Underpasses and Flyovers along Darsait – Al Wadi Al Kabir Road

Client Muscat Municipality

Consultant Renarded SA & Partners Consultanting Engineers LLC Contractor Larsen & Toubro (Oman) LLC

SAMPLING

REPORT NO:

SAMPLE ID: CORE DAI. IN MM 1OO TEST DATE:

Sampling Method Cube Cast Date

Test Specimen

Preparation

Grade of Concrete

Test Method

Test Method

Variation

TIM

E

VOLTA

GE

APPLIE

D

SPEIMENT

ID:

CELL ID: SPEIMENT

ID:

CELL ID: SPEIMENT

ID:

CELL ID:

V CURRE

NT

m

A

A TEMP OF

SLOUTI

ON

CURRE

NT

m

A

A TEMP OF

SLOUTI

ON

CURRE

NT

m

A

A TEMP OF

SLOUTI

ON

60 I0 I0 I0

60 I30 I30 I30

60 I60 I60 I60

60 I90 I90 I90

60 I120 I120 I120

60 I150 I150 I150

60 I180 I180 I180

60 I210 I210 I210

60 I240 I240 I240

60 I270 I270 I270

60 I300 I300 I300

60 I330 I330 I330

60 I360 I360 I360

Q= 0 (COULOMB) Q= 0 (COULOMB) Q= 0 (COULOMB)

QS= 0 (COULOMB) QS= 0 (COULOMB) QS= 0 (COULOMB)

QUALITATIVE CHLORIDE

ION PENETRABILITY:

QUALITATIVE CHLORIDE

ION PENETRABILITY:

QUALITATIVE CHLORIDE

ION PENETRABILITY:

COMPRESSIVE TEST Compressive strength of concrete: Out of many test applied to the concrete, this is the utmost

important which gives an idea about all the characteristics of concrete. By this single test one

judge that whether Concreting has been done properly or not. For cube test two types of

specimens either cubes of 15 cm X 15 cm X 15 cm or 10cm X 10 cm x 10 cm depending upon

the size of aggregate are used. For most of the works cubical moulds of size 15 cm x 15cm x 15

cm are commonly used.

This concrete is poured in the mould and tempered properly so as not to have any voids. After 24

hours these moulds are removed and test specimens are put in water for curing. The top surface

of these specimen should be made even and smooth. This is done by putting cement paste and

spreading smoothly on whole area of specimen.

These specimens are tested by compression testing machine after 7 days curing or 28 days

curing. Load should be applied gradually at the rate of 140 kg/cm2 per minute till the Specimens

fails. Load at the failure divided by area of specimen gives the compressive strength of concrete.

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APPARATUS

Compression testing machine (Figure 4)

Figure 3

PREPARATION OF CUBE SPECIMENS

The proportion and material for making these test specimens are from the same concrete used in

the field.

MIXING

Mix the concrete either by hand or in a laboratory batch mixer

SAMPLING

The mound is cleaned and after oil is applied, concrete is filled in layers of around 50 mm.Each

layer is compacted using a tamping rod whos dimentions are specivide under the British

Standard Code. The number of blows is also specified. Top surface is leveled and smoothened

with a trowel

CURING

The test specimens are stored in moist air for 24hours and after this period the specimens are

marked and removed from the molds and kept submerged in clear fresh water until taken out

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prior to test. The water for curing should be tested every 7days and the temperature of water

must be at 27+-2oC.

PROCEDURE

1. Remove the specimen from water after specified curing time and wipe out excess water

from the surface.

2. Take the dimension of the specimen to the nearest 0.2m

3. Clean the bearing surface of the testing machine

4. Place the specimen in the machine in such a manner that the load shall be applied to the

opposite sides of the cube cast.

5. Align the specimen centrally on the base plate of the machine.

6. Rotate the movable portion gently by hand so that it touches the top surface of the

specimen.

7. Apply the load gradually without shock and continuously at the rate of

140kg/cm2/minute till the specimen fails

8. Record the maximum load and note any unusual features in the type of failure.

RESULT

Average compressive strength of the concrete cube should be calculated in N/mm2 for 7 and 28

days. The strength of concrete increases with age. Table shows the strength of concrete at

different ages in comparison with the strength at 28 days after casting.

Age Strength per cent

1 day 16%

3 days 40%

7 days 65%

14 days 90%

28 days 99%

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WATER PERMEABILITY TEST

Objective

To determine the water permeability of concrete using a triaxial cell.

Apparatus

Permeability Apparatus (includes a triaxial cell, regulated gas pressure source, gas-over-water

accumulator, effluent volume metering device, and appropriate valves and tubing)

Theory

Water permeability is the property of concrete that is an indication of the ability for water to flow

through rocks. High permeability will allow water to move rapidly through concrete.

Permeability is affected by the pressure in concrete.

Procedure

1. Specimen: Sample specimen shall be cores drilled from concrete. They will be made and

cured in the laboratory in accordance with ASTM C 42.

2. Assembly: Attach the end plates to the specimen with two layers of electrical tape prior to

assembly. A rubber sleeve shall be placed around the specimen with stainless steel

perforated end plates against specimen ends. A porous 0.16-mm-thick layer of stainless

steel mesh shall be used on each end of specimen between the specimen and the end

plates. The rubber sleeve shall be clamped to the end plates using hose clamps. Place the

assembly inside the holder. Install the end plates on the triaxial cell. The cell shall be

tilled with deionized water through the side valve. Bleed all entrapped air from the

interior of the triaxial cell using the side valves.

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3. Selection of Driving and Confining Pressure: The confining pressure shall be no greater

than one-half the estimated unconfined compressive strength of the concrete specimen.

The drive pressure shall be no greater than 80 percent of the confining pressure.

4. Operation:. Apply the confining pressure through the confining pressure regulating

valve. Apply the drive pressure to the gas/water accumulator system through the drive

pressure regulating valve. Record the date, time to the nearest minute, drive pressure, and

confining pressure. Periodically record the date, time, drive pressure, confining pressure,

and effluent volume in mL. Make any adjustments necessary to the pressure

5. regulating valves in both the drive and confining systems to maintain them within ± 5%

of the predetermined levels. The required time interval between measurements will vary

with the permeability of the specimen from a few minutes to several hours. Plot the total

volume of fluid collected versus elapsed time for the test. When the resulting curve is

linear over five or more readings, steady-state flow is obtained.

Report

8.1 The report shall include the following:

WATER PERMEABILITY TEST

Name of Project: Design & Construction of Underpasses and Flyovers along Darsait- Al

Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Source Date of Casting

Description Date Testing

Grade of Concrete Location of Test

Specimen

Water Cement Ratio Type of Cement

Maximum Size of

Aggregate

Age @ Start of Test 28 Days

Nominal Size of Test

Specimens

150X150X150 MM Test Method DIN 1048: Part

5:1991

Result of DIN Water Permeability Test

Sample Reference No.

Density Prior to Test

(kg/m3)

Test RESULT

Max. depth of Water

Penetration (mm)

Average

Specifications Limit:

Remarks:

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SIEVE ANALYSIS TEST

A sieve analysis is a practice or procedure used to assess the particle size distribution of a

granular material. The size distribution is often of critical importance to the way the material

performs in use. Being such a simple technique of particle sizing, it is probably the most

common. The purpose of this test is to determine the particle size distribution of fine and coarse

aggregates by sieving as per British Standard codes.

PRINCIPLE

By passing the sample downward through a series of standard sieves, each of

decreasing size openings, the aggregates are separated into several groups, each of

which contains aggregates in a particular size range.

APPARATUS

A set of IS Sieves of sizes - 63mm, 50mm, 37.5mm, 25mm, 19mm,

9.5mm, 4.75mm, 2mm, 0.45mm, 0.075mm

Balance or scale with an accuracy to measure 0.1 percent of the weight of the test sample

PROCEDURE

1. The test sample is dried and weighed.

2. The sample is sieved by using a set of BS Sieves.

3. After completing 4.75 mm, the remaining sample is washed and dried and then finally is

allowed to pass through the remaining sieves.

4. On completion of sieving, the material on each sieve is weighed.

5. Cumulative weight passing through each sieve is calculated as a percentage of the total

sample weight.

6. Fineness modulus is obtained by adding cumulative percentage of aggregates retained on

each sieve and dividing the sum by 100.

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INTERPRETATION OF RESULTS

The results are presented in a graph of percent passing versus the sieve size. On the graph the

sieve size scale is logarithmic. The following should be calculated:

The cumulative percentage by weight of the total sample

The percentage by weight of the total sample passing through one sieve and retained on

the next smaller sieve.

Gradation affects many properties of an aggregate. It affects bulk density, physical stability and

permeability. With careful selection of the gradation, it is possible to achieve high bulk density,

high physical stability, and low permeability.

PENETRATION OF BITUMEN TEST

Objective

To examine the consistency of a sample of bitumen by determining the distance in tenths of a

millimeter that a standard needle vertically penetrates the bitumen specimen to be used for the

construction of flyovers along Darsait- Al Wadi Al Kabir Road under known conditions of

loading, time and temperature.

Apparatus

Penetration Apparatus

Needle

Container

Water Bath

Thermometer for Water Bath

Stop watch

Theory

It measures the hardness or softness of bitumen by measuring the depth in tenths of a millimeter

to which a standard loaded needle will penetrate vertically in 5 seconds. This is the most widely

used method of measuring the consistency of a bituminous material at a given temperature. It is a

means of classification rather than a measure of quality.

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Procedure

1. Heat the sample until it becomes fluid.

2. Pour it in a container to a depth such that when cooled, the depth of sample is at least

10mm greater than the expected penetration.

3. Allow it to cool in an atmospheric temperature.

4. Clean the needle and place a weight above the needle.

5. Use the water bath to maintain the temperature of specimen.

6. Mount the needle on bitumen, such that it should just touch the surface of bitumen.

7. Then start the stop watch and allow the penetration needle to penetrate freely at same

time for 5 seconds. After 5 seconds stop the penetration.

8. Result will be the grade of bitumen.

9. Take at least three reading.

PENETRATION OF BITUMEN

Name of Project: Design & Construction of Underpasses and Flyovers along Darsait- Al

Wadi Al Kabir Road

Client: Muscat Municipality

Consultant: Renardet SA & Partners Consulting Engineer LLC

Contractor: Larsen & Toubro (Oman) LLC

Sample No. Date of Sampling

Location Date of Testing

Source Test Method

Grade of Bitumen Sampled By

Sampling Method

Test No. 1 2 3

Load (g)

Time (seconds)

Temperature (oC)

Initial Reading

Final Reading

Penetration of

Bitumen (0.1 mm)

Average Penetration

(0.1 mm)

Specification Limit

(0.1 mm)

Remarks:

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PROJECT EXECUTION

METHOD STATEMENT FOR REINFORCEMENT WORKS These method statements are the statements issued by the Quality Department

for the management and implementation methods for the engineering,

fabrication, transportation, installation and testing of major materials .

Fabrication of Reinforcement

Approved reinforcement drawings and Bar Bending Schedules will be obtained well in

advance, to plan fabrication of Reinforcement steel.

Required quantity of approved reinforcement steel bars of specified diameter(s) will be

shifted from the stockyard to the fabrication shop by manual / mechanical means.

At fabrication shop, bars will be cut to required size and bent to required shape. Bending

of reinforcements will be carried out as per the bar bending schedule.

Record of material receipt (on day basis) at fabrication yard will be maintained by the

concerned Engineer in charge, in a register indicating the following:

1. Date of receipt

2. Diameter of bar

3. Lot Number

Records of reinforcement fabrication will be maintained to reflect the work done for the

day. The same will be informed to the Planning section.

Fabricated bars will be shifted to respective steel yard which is part of the construction

yard and the lot will be tagged indicating the following:

1. Structure

2. Diameter

3. Bar Mark

4. Shape

5. Number of bars

Cut & bend reinforcement bars will be dispatched to site from the steel yard according to

the dispatch schedule as per Construction Programme. Records of requisition from site &

materials issued to site will be maintained.

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Splicing of reinforcement will be carried out as per the bar bending schedule planned by

the respective Section in-charges. Testing of the spliced samples & acceptance criteria

will be at the required frequency as per the relevant code

Transportation & Safety

Reinforcement bars will be transported from the fabrication yard/steel yard to the

respective job sites. At the main job site, rebar will be handled manually / mechanically

for shifting and laying activities.

Due care shall be paid for ensuring that the bars do not suffer any damage and are safely

handled.

Testing Of Materials

Reinforcement (High Yield steel deformed bars) will be as per BS 4449 with a minimum

yield stress of 485 N/sqmm, Material test certificate will be obtained from manufacturer

from each and every lot and size.

Mill certificate and test records from manufacturers/suppliers to be submitted before

delivery of the reinforcement

Laying of Reinforcement

Reinforcement bars shall be laid in position as per the relevant approved Reinforcement

drawings. Ensure the reinforcing steel is free from loose flaky rust, mud, oil or other

coatings that will destroy or reduce the bond.

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Required concrete Cover shall be provided to the reinforcement bars by means of cover

blocks/spacers of specified size. Spliced reinforcement bars shall be laid and staggered as

per the requirement of drawing. Unless otherwise specified, full length of bars shall be

made up by lapping, meeting the lap staggering as per specified requirement and securely

tied with 1.6 mm galvanized coated tie wire.

Spacer block will be made of approved material.

Bars shall be laid in required line and level, as well as spacing of the bars and lap length

shall be as per relevant latest approved reinforcement drawings.

In congested areas, reinforcement bars shall be temporarily flared to facilitate placement

and compaction of concrete and shall be brought back to position before concrete reaches

that portion. Reinforcement bars shall be tied to each other with annealed binding wire at

all the joints

Fixing of anchor bolts / sleeves / embedded parts or supports

Accepted / approved anchor bolts / sleeves / embedded parts shall be positioned at the

specified locations as per the drawing. These items shall be firmly fixed to the

reinforcement by means of binding wire or by supporting elements, if required so that

their position will not be affected at the time of concreting.

All supports will be precast concrete blocks of same strength to that of the surrounding

concrete and size will be as per the drawing.

Welded-Wire Fabric / Dowels

Welded wire fabric and Dowels will be placed in slabs as indicated in drawings. Wire

fabric laps will be staggered to avoid continuous laps in either direction. Dowels will be

accurately aligned and rigidly supported.

METHOD STATEMENT FOR FORM WORK

These method statements are the statements issued by the Quality Department

for the management and implementation methods for the engineering,

fabrication, transportation, installation and testing of major materials .

Formwork and supporting structure will be designed considering following parameters:

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Unit wt. of concrete

Placement temperature of concrete

Rate of pouring of concrete

Pouring sequence

Formwork design shall cater for fluid concrete pressure, dead load, self-weight of form

and scaffold, construction live loads, and wind load wherever applicable.

Formwork shall be designed to limit deflections within specified tolerances for each

structure.

Fabrication:

Formwork will be fabricated at the carpentry shop at project site. Fabrication involves

forming panels (shutter panels) to the required shapes and sizes by nailing / screwing

backing timber members to plywood and clamping the panels to steel walers.

As far as possible formwork will be standardized, this will permit the reuse of sections

with alteration.

In case of proprietary items, manufacturer recommendations will be followed for design

& system application. The fabricated shutters will be free from oil, grease, concrete

deposits, holes, gaps, protruded nails, etc. Small pieces for closing on to will be

fabricated insitu.

Formwork will be transported from the carpentry yard and installed at the site as per the

drawing.

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Formwork material will be wood, plywood or steel of sufficient strength, straight and free

from warp, twist, splits, unnecessary holes or other defects. Form material will be reused

if the surface is good enough to give the required finish as per specification.

Plywood forms will be of required length, height and thickness.

PROPOSED METHOD OF CONSTRUCTION

Sequence of Major Events

Fixing

Fabricated form panels will be assembled and supported in-situ. Alignment will be

ensured with plumb bob / optical plummet and Calibrated survey instruments (Theodolite

and auto levels).

Beadings and other special shutters required to create grooves will be accurately sized at

the central carpentry shop and fixed to the shutter panels at the desired location.

The formwork will be checked for leak proof, coating of form oil, proper support &

fixing of shutters, securing of wedges, firmly fixing of jacks to produce concrete surfaces

meeting the surface requirements of specification.

Once the propping & decking works are completed to the required size of grid, 18 mm

thick film face shuttering plywood is placed over horizontally in level &line and the

joints are scaled with special tape if required to ensure its joints are leak proof to the

complete satisfaction of the engineer.

Watch the formwork during concreting. In case of minute leakage, bulge / sag; adjust it

accordingly before the initial set of concrete.

Forms concrete surfaces will be coated with an approved form releasing agent as per the

manufacturer’s instruction.

Removal of Forms:

For concrete using Ordinary Portland cement, the following minimum periods shall

elapse, after placing of concrete has been completed before removal of forms shall be

commenced

Slabs on Grade, sides of beams, Pier columns and Retaining walls – 48 hours.

Slabs and beam sofits – 10 days.

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During form removal, no damage to concrete surface shall be ensured.

Clean & stack the removed form properly on even surface. Stack steel components,

shutters, supports; pins anchor plates, etc in separate place without disturbing the next

activities.

METHOD STATEMENT FOR CONCRETE WORKS These method statements are the statements issued by the Quality Department

for the management and implementation methods for the engineering,

fabrication, transportation, installation and testing of major materials .

a) Engineering: Approval of mix proportions and concrete pour clearances will be obtained

well in advance as required.

b) Mixing: Concrete will be mixed in the approved batching plant as per section: 501 of

specifications

c) Transportation: Concrete will be transported in the Transit Mixers to the site without

segregation.

d) Placing: Concrete will be placed either with pump or with other suitable equipment

without segregation.

e) Testing of major materials: Major materials Coarse and Fine aggregates will be tested

regularly as per the frequency. All other tests will be done at the time of source approval.

Material Test certificate of cement and Admixture will be obtained for each lot. And also

water will be tested for source approval.

PROPOSED METHOD OF CONSTRUCTION

Mix proportion:

Necessary Laboratory Trials will be carried out to arrive at a mix proportion for different

grades of Concrete. Concrete will be workable and meet the requirement of strength

criteria along with durability.

In addition to determination of Mix Proportion, particular attention will be given to

physical properties such as Workability, Cohesiveness, Plasticity, Slump and

Temperatures ,Proportioning of Pumpable Concrete will be done keeping in mind its

additional requirements of fluidity, non-segregation, cohesion and plasticity in green

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condition, in addition to achieving the desired properties of Hardened State. Routine

calibration of the Batching plant will be carried out.

Ingredients, admixtures and proportioning approvals will be obtained prior to the

concrete works.

CONCRETE PRODUCTION The requisition for the concrete will be placed only when the pour is ready in all respects.

The Concrete will be arranged from the approved ready mix plant. Record the mix details

in the batch sheet format.

Transportation:

Concrete will be transported from the Batching Plant to the site in transit mixers without

any segregation.

Concrete will be transported with all precautions to prevent loss of water by evaporation

in hot weather and heat loss in cold weather conditions. No concrete will be transported

and placed in open, while it rains.

The transit mixer will have dispatch slip with batch details including concrete grade,

quantity, date, time of dispatch, etc. Copies of the dispatch slip will be submitted to

inspectors.

Placement:

Blinding concrete will be done on the clean surface after successful completion of

excavation, level survey, backfilling, compaction and testing. Necessary approval will be

obtained to start the blinding.

Placing method will depend on rate of concrete planned, type of structure, quantity, rate

of placement of concrete to be poured, the equipment available for compacting and

placing the Concrete, formwork design and initial setting time of Concrete.

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Provision for cast in services / cut outs will be done as per approved drawing.

Construction and expansion joints will be done as per specification.

Once all reinforcements are placed and aligned, embedded parts and formwork are

securely held in position and is duly inspected 24 hours information will be given in

writing to the Engineer in charge through pour card, seeking his permission for pouring

the Concrete.

All loose materials will be removed, and light water sprinkling will be done before

placement of concrete.

Concrete will be laid continuously in uniform layers.

Concrete will not free fall from a height not greater than 1.5m to prevent from

segregation.

For locations where direct placement is not possible and in particular through narrow

forms, suitable drop chutes or ‘Elephant Trunk’ will be provided. Long troughs, chutes

and pipes will be kept free from coatings of hardened concrete. Open troughs and chutes

will be of metal or metal lined.

Concrete pours will be taken up in the sequences as shown in the relevant drawings. Pour

sequence will be such that next layer of concrete is placed over the layer beneath within

one hour to avoid formation of cold joints.

Concrete will be placed carefully to avoid displacement of reinforcements and anchor

bolts, anchorage sleeves, PVC water stop if any.

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Placing of concrete in supported elements will not be started until the concrete previously

placed in walls & columns is no longer plastic and has been in place for at least two

hours.

Suitable measures to prevent the excessive moisture loss from the concrete will be taken.

Polythene sheet will be placed immediately on fresh concrete to prevent evaporation

losses and followed by Wet Hessian cloth. Water will be sprinkled around the structure to

avoid the dust contamination.

During night concreting proper lighting will be provided.

Compaction of Concrete:

Each layer of Fresh Concrete will be compacted by vibrators to the minimum practicable

consolidated volume. Compacted concrete will be free from pockets of coarse aggregates

and will be flush and placed tight against all form surfaces. Mechanical vibration will be

supplemented by hand spading and tamping, particularly at the corners to assure

elimination of pockets.

The vibrators will be inserted in vertical position at points approximately 450mm apart.

The vibrators will be withdrawn slowly out of the Concrete. The spacing will provide

some overlapping of the area vibrated at each insertion. Over vibration will be avoided.

Vibrator needle will be inserted vertically inside the Concrete and will be allowed to

penetrate down by its own weight. Vibration will not be stopped when needle is

immersed in Concrete. At each insertion, the duration will be sufficient to consolidate the

concrete but not sufficient to cause segregation, generally from 10 to 20 seconds.

The vibrator will penetrate fully into the layer being placed and also about 50 mm into

the previous layer, while the layer beneath it is still plastic, to ensure good bond and

homogeneity between the two layers and prevent the formation of cold joint. Care will be

taken so that the vibrator does not touch formwork, and rebar anchorage devices .The

needle vibrator will not be used to drag or spread the concrete.

The motor’s driving the vibrators and active vibrators will not be rested directly on

reinforcements.

A Spare vibrator & needles will be available for critical placements.

Once the concrete placement is started, placement will continue until the panel or section

is completed or until a suitable construction joint is reached.

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Concrete Finish:

Care to taken from the evaporation of water losses from the compacted concrete.

Polythene sheets will be placed over the concrete if there is a lag between completion of

compaction, leveling and finishing operations.

Formed surfaces exposed to view will have finish as mentioned in the drawing. Concrete

slabs on grade & elevated slabs will have a texture finish. Dusting of surfaces with dry

cement to absorb excess water will not be permitted.

Final finish of the concrete will be as per finishes schedule/as per Spec or as mentioned in

drawings.

Protection and curing of concrete:

Concrete after finish will be protected from damages till its final setting. Also it will be

protected against damage by other activities till it gains required strength.

Curing of concrete members will be done for 7 days for normal concrete and 10days for

Silica fume concrete. Retain moisture and maintain reasonably constant temperature in

concrete for the duration of the curing period.

Water Curing is achieved using approved water in combination with gunny sacks/

Hessian and Polythene sheet to ensure the concrete is continuously damp.

Horizontal surface will be covered with plastic sheet immediately after finish. Once

initial set is over, plastic sheet will be removed and wet Hessian will be placed and over

that plastic sheer to be covered.

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Curing of vertical surface will be done as soon as it is stripped off. Top surface will be

kept wet by Hessian cloth and sides will be wrapped with Hessian followed by plastic

sheet tied firmly.

Post concrete Inspection:

Post concrete inspection will be carried out after removal of shuttering for identifying

defects like honeycombed surface, any other defects. Rectification measures, as

necessary, will be executed as per approved repair mortar with manufacturer

recommended procedure, and records will be maintained

Treatment of defects on formed surfaces will not be done without approval of the

engineer.

Defective concrete & repairs to concrete will be done as per approval.

All the concrete surfaces must be kept always clean.

SPECIAL COATING SYSTEM FOR THE PROTECTION OF EXPOSED CONCRETE SURFACES

Description

Under this work the contractor shall furnish and apply, in accordance with these

specifications, a Special Protective Coating System to exposed concrete surfaces, at

locations indicated on the plans or where directed by the Engineer.

In addition, all structural concrete surfaces such as insides of elevator shafts, that are not

to be coated with complete coating system shall be coated using 1 or 2 coats of the

penetrating primer as directed by the Engineer and to his satisfaction and approval.

Materials

The coating system shall be an elastomeric system of single component product, a

weather resistant top coat used in conjunction with a penetration primer. The coating

shall have the ability to provide in-depth protection for reinforced concrete structures

against corrosion associated with the ingress of chloride and sulphate ions, carbon

dioxide and other air-borne acid gases, and shall have the sbility to allow water vapour to

escape from the structure.

Proprietary special coating system for the protection of exposed concrete surfaces shall

be proposed by the Contractor and is subjected to the Engineer’s approval. All materials

shall be from an approved by the Contractor and is subject to the Engineer’s approval. All

materials shall be from an approved manufacturer whose products have proven to be

highly satisfactory in similar works in environmental conditions similar to those

experienced in Muscat, Oman. In this respect the Contractor, when submitting for

approval the coating system proposed to be used, shall enclose also a list of works,

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executed in environmental conditions similar to those experimented in Muscat, Oman, in

which the same system was successfully used.

The Contractor’s application shall be accompanied by the manufacturer’s detailed

product specifications together with application instructions, and guarantee that the

product is suitable for use at the operating temperatures in Muscat, Oman.

Primer

The primer shall be a low viscosity reactive silane- siloxane/ acrylic blend dissolved in a

penetrating organic carrier. The primer shall have the capability to penetrate and produce

a chemically bound Hydrophobic barrier to prevent the passage of chloride and sulphate

ions. The primer should also be film forming to condition and stabilize the substrate prior

to the application of the topcoat. The primer should be applied in full accordance with the

manufacturer’s instructions.

Topcoat

The top coat shall be pure aliphatic acrylic resin, UV resistant, decorative, high

performance water or solvent based, pigmented coating. It shall have resistance to water,

carbon dioxide and other air- borne acids and have the ability to allow the passage of

water vapour from within the structure.

The top coat shall have elastomeric and flexural capabilities and should be applied in

strict accordance with the manufacturer’s instructions.

In addition, all structural concrete surface such as insiders of box sections and culverts as

shown in the drawings that are not to be coated with full system, shall be completely

coated using 1 or 2 coats of the penetrating primer as directed by the engineer and to his

or her satisfaction and approval.

The Contractor shall provide evidence, for the Engineer’s approval, that the coating

system shall render the concrete surface satisfying the following criteria.

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CRITERIA REQUIREMENT

Anti- carbonation

Carbon dioxide diffusion coefficient Less than 8x10-8

cm2/s

Chloride Ingress, Chloride ion diffusion

coefficient

Less than 5x10-9

cm2/s

Crack bridging ability (Modified ASTM C836-

884 at 20oC)

More than 1 mm

Breathability

Water vapour diffusion coefficient Greater than 3.5x10-5

cm2/s

Reduction in Water Absorption (measured

against a control Concrete sample in

accordance with ASTM C642)

82% minimum at 28 Days

Reduction in Chloride Ion Penetration 90% minimum at 28 Days

Water Vapour Transmission > 13 g/m2/day

Carbon Dioxide Diffusion Resistance Equivalent to 500 mm of 30 N/mm2 concrete

Dry film thickness Minimum 250 to 300 microns

Adhesion Minimum 1.0 Mpa

Adhesion after exposure to salinated fog Minimum 1.0 Mpa

Resistance to humidity and heat No loss of adhesion, No cracking, No

bubbling, No change in colour, No dust

Resistance to impact No cracking, No un-sticking

Resistance to abrasion Maximum loss of weight 25mg/100 abrasions

Resistance to salinated fog No dusting, No cracking, No un-sticking, No

bubbling

Sloar infra red rays Re-radiation 95%

Ultra violet rays Re-radiation 85%

These protection characteristics shall be determined by test methods approved by the

engineer.

CONSTRUCTION REQUIREMENTS

Trial Panels

Prior to applying the system in the works, trial applications shall be carried out on trial

panels made by the contractor. The trails will demonstrate the method proposed for

applying the system, coverage, coating thickness, colour and final appearance of the

coating. Representatives of the coating manufacturers shall be present at the trails and the

surface preparation and application of the coating shall be carried out under their

direction. The contractor shall at his or her own expense surface coat as many panels as

required by the engineer until a trial panel has been accepted by the engineer as

satisfactory. The coated panel, when accepted will form the standard against which the

corresponding coating in the works will be judges. No application of the coating in the

works shall be undertaken until trials have been completed to the engineer’s satisfaction.

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Inspection of Concrete

The contractor shall not proceed with the surface finish or making good of concrete

surfaces until he has received the engineer’s representative’s permission to do so and he

shall not apply cement slurry or mortar or any other coating to the concrete surfaces from

which the shuttering has been struck until the concrete has been inspected and approved

by the engineer’s representative.

Approval Prior to Coating Application in the Works

The engineer’s approval must be obtained prior to applying the coating system in the

works. Before approval is given the engineer will need to be satisfied as per the

following:

All Construction work in the immediate vicinity of the surface to be coated has been

completed.

The surface preparation of the surface has been completed.

Adequate measures have been taken to protect the property of third parties, including

vehicles, from coating splatters.

The weather conditions accord with the coating manufacturer’s directions for coating

application.

Method of Measurement

Payment will be made at the price bid per square meter for the number of square meters

of protective coating applied, stated in the Estimate of Quantities shown on the Contract

Plans.

Basis of Payment

The unit price bid per square meter shall include the cost of furnishing all labor,

materials, and equipment necessary to satisfactorily complete the work.

Items in the Bill of Quantities

Special Coating System for the Protection of Exposed Concrete Surfaces

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HIGHWAY CONSTRUCTION The soil profile for the construction of a road or a highway is given as follows:

Embankment

Subgrade

Granular Sub Base

Crushed Aggregate Base Course

EMBANKMENT A road is normally raised onto an embankment made of earth to avoid a change in level required

by the terrain, the alternatives being either to have an unacceptable change in level or detour to

follow a contour. A cutting is used for the same purpose where the land is originally higher than

required. Embankments are often constructed using material obtained from a cutting.

Embankments should be constructed using suitable materials to provide adequate support to the

formation and long-term stability.

SUBGRADE

Subgrade is the native material underneath a constructed road pavement. It is also

called formation level.The term can also refer to imported material that has been used to build

an embankment.

Subgrades are commonly compacted before the construction of a road or pavement, and are

sometimes stabilized by the addition of asphalt, lime, portland cement or other modifiers. The

subgrade is the foundation of the pavement structure, on which the subbase is laid.

The load-bearing strength of subgrade is measured by California Bearing Ratio (CBR)

test, falling weight deflectometer back calculations and other methods.

GRANULAR SUB BASE

Sub-base is the layer of aggregate material laid on the subgrade, on which the base course layer

is located. It may be omitted when there will be only foot traffic on the pavement, but it is

necessary for surfaces used by vehicles.

Subbase is often the main load-bearing layer of the pavement. Its role is to spread the load evenly

over the subgrade. The materials used may be either unbound granular, or cement-bound. The

quality of subbase is very important for the useful life of the road. Unbound granular materials

are usually crushed stone, crushed slag or concrete, or slate.

Cement-bound materials come in multiple types. Mass concrete is used where exceptional loads

are expected, with thickness usually 100-150 mm, and optional reinforcement with steel mesh or

polymer fibers. Other cement bound materials (CBM), with less strength but also lower cost, are

used. They are rated by strength, from the weakest CBM 1 (also formerly known as soil cement)

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through CBM 2 to CBM 3, 4, and 5, which are more similar to concrete and are called "lean

mix".

The thickness of subbase can range from 75-100 mm for garden paths through 100-150 mm for

driveways and public footpaths, to 150-225 mm for heavy used roads, and more for highways.

Low quality subbase material should not be accepted, including large pieces of rock and

concrete.

CRUSHED AGGREGATE BASE COURSE

The base course or basecourse in pavements is a layer of material in an asphalt roadway that is

located directly under the surface layer.

If there is a subbase course, the base course is constructed directly above this layer. Otherwise, it

is built directly on top of the subgrade. Typical base course thickness ranges from 4 to 6 inches

and is governed by underlying layer properties. Generally consisting of a specific type

of construction aggregate, it is placed by means of attentive spreading and compacting to a

minimum of 95% relative compaction, thus providing the stable foundation needed to support

either additional layers of aggregates or the placement of an asphalt concrete wearing

course which is applied directly on top of the base course.

Aggregate Base (AB) is typically made of a recipe of mixing different sizes of crushed

rock together forming the Aggregate which has certain desirable properties. 3/4 inch Aggregate

Base, Class 2, is used in roadways and is an aggregate made of a specific recipe of different sizes

and quality of rock inclusive of 3⁄4 in (19.05 mm) to fine dust. An aggregate is normally made

from newly quarried rock, or it is sometimes allowed to be made from recycled asphalt concrete

and/or Portland cement concrete.

In Oman, the following standards are followed for the construction of roads and highways:

BS Standards

BSEN Standards

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ASTN Standards

ASTHO Standards

Compaction test is conducted for each layer. If the soil is not found suitable, then it is

excavagated and the suitable soil with desirable properties are placed. This is called cutting. Each

material must be approved by the consultant and the contractor before it is implemented on site.

All specifications for road design and construction are given by the Muscat Municipality and

Parsons International LLC. For each layers, surveyors are pre-marking the depth of the laers and

verifying as per the drawing design. Inspection on compaction and quality is also done

simultaneously.

Overall Cross section of a road from the top to bottom is given as below along with their

respective depth:

Bituminous Course 50 mm

Bituminus Base Course (2nd

Layer) 60 mm

Bituminus Base Course (1st Layer) 60 mm

Aggregate Base Course (2nd

Layer) 100 mm

Aggregate Base Course (1st Layer) 100 mm

Granular Sub Base 300 mm

Subgrade 200 mm

Embankment (in India) 500 mm

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The entire construction is done by laying 200 mm of the respective layers at a time. The

bituminous base course all together is called asphalt and lying of this layer is called asphalting.

Asphalting is done using a paving machine.

After asphalting is done, it is compacted (approximately 97%) at a temperature of 110oC using

rollers. Asphalt mix design is done as per the temperature of that region. A total of 3 layers of

asphalting is done to make the road strong.

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FOOTPATH

Footpath is made by using interlocks as shown below. From the road level, the level of footpath

is 200 mm high. A curb is inserted between the interlock and the road for stability. This curb has

a height of 350 mm.

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CONCLUSION It was a wonderful learning experience at Larsen & Toubro (Oman) LLC. “Design and

Construction of Flyovers and Underpasses along the Darsait –Al Wadi Al Kabir Road”. I gained

a lot of insight regarding almost every aspect of the construction of bridges and highways. The

friendly welcome from all the employees appreciating, sharing their experience and giving their

piece of wisdom which they havegained in long journey of work. I am very much thankful for

the wonderful accommodation from Larsen & Toubro (Oman) LLC. I hope this experience will

surely help me in my future and also in shaping my career.

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REFERENCE http://www.uic.edu/classes/cemm/cemmlab/Experiment%207-Atterberg%20Limits.pdf

http://en.wikipedia.org/wiki/Atterberg_limits#Plastic_limit

http://www.bc.cityu.edu.hk/~soillab/exp/Download/EXPeriment-4.pdf

http://www.iamcivilengineer.com/2013/11/california-bearing-ratio-cbr-for.html

http://civil.unm.edu/classes/content/ce_305/CE_305_files/New_CE_Website/laboratories_ss/pcc

/laabrasion.html

http://theconstructor.org/building/building-material/determination-of-los-angeles-abrasion-

value/1361/

http://indepthexploration.co.uk/Aggregates/BS_ACV_812/Aggregate%20Crushing%20Value%2

0BS%20812-110%20and%20BS%20EN%201097-2.pdf

http://www.caer.uky.edu/kyasheducation/testing-concrete.shtml

http://en.wikipedia.org/wiki/Subgrade

http://en.wikipedia.org/wiki/Base_course

http://en.wikipedia.org/wiki/Embankment_(transportation)

http://en.wikipedia.org/wiki/Subbase_(pavement)

http://en.wikipedia.org/wiki/Subgrade

http://en.wikipedia.org/wiki/Footpath