In-Plant Training Report

1

Sri Lanka Institute Of Information

Technology

Report on In-Plant Training

At

Civil & Structural Engineering Consultants (PVT).Ltd

Name: Samraweera S.R.L.L

Registered No: EN13529932

Course: Civil Engineering

Field of Specialization: Construction of Super Structures & Pile Construction

Period of Training: 3 Months

i

Abstract This report is an in-plant training report submitted in partial fulfillment of the requirements

for the B.Sc. Civil Engineering as per norms of Sri Lanka Institute of Information

Technology. The author visited the site for construction of super structure at Lotus Tower

Colombo & pile construction of Avic Astoria Residence Colombo 03 during this training

period and attained technical knowledge and practical experience, after which was able to

compile this report .The report consist of brief study and description of materials, equipment

and procedures used at the site for construction. Author put his best to elaborate the actual

site conditions and problem faced at site and the strategy used to deal with them.

The main objective in this report to present the fundamental aspects of practical requirements.

The sites in this report the objective was to introduce, wherever necessary material which

embodies the most advanced and recent methodologies.

Chapter 1 Discusses introduction to vision & mission, organization profile and Service

management. Chapter 2 discusses training experience and it contain summery of duties,

project involved and problem encountered & approach of solving and Chapter 3 deal with the

conclusion.

In spite of every care taken, it is possible that some errors might have been left unnoticed the

author sincerely welcomes the constructive criticism for improving report.

ii

Acknowledgement

First and fore most may I take this opportunity to thank all those who collaborated with me to

make a success of this venture. Generally my gratitude is forwarded to the Sri Lanka Institute

Information Technology (SLLIT) for its direction and invaluable advice given. Especially my

humble thanks and regards are mentioned to our Industrial Training Coordinator Mr.

Kalyanapala and the Departmental Adviser of Civil Engineering Dr.G.N. Samarasekara.

Civil & Structural Engineering Consultants company which was given this great opportunity

I highly appreciate and more over the person who directed advised us in our enterprise is Mr.

Shiromal Fernando who is one of the leading structural engineer in Sri Lanka and he has

been responsible for many high rise buildings in this country.

iii

Table of Contents

Abstract .................................................................................................................................................... i

Acknowledgement .................................................................................................................................. ii

List of Figures ........................................................................................................................................ iv

List of Tables ......................................................................................................................................... vi

1. Introduction ...................................................................................................................................... 1

1.1. Company profile ........................................................................................................................ 1

1.2. Company Vision ........................................................................................................................ 1

1.3 .Mission ....................................................................................................................................... 1

1.4. Services ...................................................................................................................................... 2

2. Training Experience ......................................................................................................................... 4

2.1. Training Experience in Lotus Tower ............................................................................................... 4

2.1.1. Materials ............................................................................................................................... 6

2.1.2. Equipment ............................................................................................................................. 9

2.1.3. Duties carried out in Lotus .................................................................................................. 11

2.2. Training experience at Avic Astoria Residence ............................................................................. 17

2.2.1. Materials ............................................................................................................................. 18

2.2.2. Equipment ........................................................................................................................... 20

2.2.3. Summary of site work in Avic Astoria ............................................................................... 24

2.2.4. Duties at Avic Astoria ......................................................................................................... 27

2.2.5. Problems encountered in Avic ............................................................................................ 34

3. Conclusion ...................................................................................................................................... 35

References ............................................................................................................................................. 36

Appendices ........................................................................................................................................... 36

iv

List of Figures Figure 01: TRCSL Logo ......................................................................................................................... 4

Figure 02: Moratuwa University Logo ................................................................................................... 4

Figure 03: CEIEC Logo .......................................................................................................................... 4

Figure 04:Lotus Tower ........................................................................................................................... 5

Figure 05:Front Elevation of Lotus Tower ............................................................................................. 5

Figure 06: Reinforcement Diagram of Tower Body Inner Tube ............................................................ 7

Figure 07: Walls of Lift (Elevators) & Wall of Stair Case ..................................................................... 7

Figure 08: Reinforcement Diagram of Outer Tube ................................................................................. 8

Figure 09: Post-Tension cables ............................................................................................................... 8

Figure 10: Tower Crane .......................................................................................................................... 9

Figure 11: Concrete Vibrator ................................................................................................................ 10

Figure 12: Concrete placing boom ........................................................................................................ 10

Figure 13: Concrete Ingredients ............................................................................................................ 11

Figure 14: Measuring scalar with wet sand sample .............................................................................. 12

Figure 15: Heating the sample of aggregate & sand ............................................................................. 12

Figure 16: Measuring weights of dry samples ...................................................................................... 12

Figure 17: Hydraulic Anchor Pull Out Testing Kit ............................................................................... 14

Figure 18: Installing hydraulic disc in to steel bar ................................................................................ 14

Figure 19: Adjusting gauge in to zero ................................................................................................... 14

Figure 20: Appling pressure force ........................................................................................................ 15

Figure 21: Client Logo .......................................................................................................................... 17

Figure 22: Consultant Logo .................................................................................................................. 17

Figure 23: Contractor Logo .................................................................................................................. 17

Figure 24: Proposed Building ............................................................................................................... 17

Figure 25: Site Location ........................................................................................................................ 18

Figure 26: Sample of C30 Concrete ...................................................................................................... 19

Figure 27: Steel Lot .............................................................................................................................. 19

Figure 28: Sample of Bentonite Fluid\ .................................................................................................. 20

Figure 29: BG 26 Machine ................................................................................................................... 20

Figure 30: Crane………………………………………………………………………………………22

Figure 31: Tremie pipes ........................................................................................................................ 22

Figure 32: Excavator ............................................................................................................................. 22

Figure 33: Auto Level ........................................................................................................................... 22

Figure 34: Total Station ........................................................................................................................ 23

v

Figure 35: De-Sander (BE170) ............................................................................................................. 23

Figure 36: Rebar Thread Rolling Machine ........................................................................................... 23

Figure 37: Setting out points ................................................................................................................. 24

Figure 38: Casing Installation ............................................................................................................... 24

Figure 39: Checking Verticality of Casing ......................................................................................... 24

Figure 40: Rechecking Casing Center Coordinates .............................................................................. 24

Figure 41: Boring Work ........................................................................................................................ 25

Figure 42: De Sanding Process ............................................................................................................. 25

Figure 43: Installation of Reinforcement cage ...................................................................................... 25

Figure 44: Installing Tremie pipe System in to Bored pile ................................................................ 26

Figure 45: Concreting .......................................................................................................................... 26

Figure 46: Casing Removal .................................................................................................................. 26

Figure 47: Mud Balance Kit.................................................................................................................. 27

Figure 48: Filling Bentonite in to Cup .................................................................................................. 27

Figure 49: Closing cup with Vent Hole ................................................................................................ 27

Figure 50: Seating Mud Balance on to Fulcrum ................................................................................... 28

Figure 51: Density Reading .................................................................................................................. 28

Figure 52: Marsh Funnel with Cup ....................................................................................................... 28

Figure 53: Filling Bentonite in to Marsh Funnel .................................................................................. 29

Figure 54: Measuring time for fill the cup ............................................................................................ 29

Figure 55: Apparatus of PIT ................................................................................................................. 29

Figure 56: Clean the surface of the pile head ........................................................................................ 30

Figure 57: Attach the Accelerometer…………………… .................................................................... 30

Figure 58: Tap the pile head with a hammer ..................................................................................... 30

Figure 59: Record the Wave Details ..................................................................................................... 30

Figure 60: Test Result of 900mm Diameter Pile &1200mm Pile ......................................................... 30

Figure 61: Apparatus of Dynamic Pile Test .......................................................................................... 31

Figure 62: Pile Head Covered with a steel Casing ................................................................................ 31

Figure 63: Measuring Staff reading ...................................................................................................... 32

Figure 64: Guide frame with Steel Loads ............................................................................................. 32

Figure 65: Lifting steel loads upward by using Hydraulic jack ............................................................ 32

Figure 66: Releasing Loads in to Pile Top ............................................................................................ 33

Figure 67: Measuring Results ............................................................................................................... 33

Figure 68: PDA Results ........................................................................................................................ 33

Figure 69: Elevation Diagram ............................................................................................................... 37

vi

List of Tables

Table 01: Project details .......................................................................................................................... 3

Table 02: C50 Concrete Mixture Ratio ................................................................................................... 6

Table 03: Reinforcement details of Inner Tube ...................................................................................... 7

Table 04: Reinforcement details of Walls of Lift (Elevators) & Wall of Stair Case .............................. 7

Table 05: Reinforcement details of Wall of Outer Tube ......................................................................... 8

Table 06: Results of tested specimen .................................................................................................... 15

Table 07: Details of Structural Piles ..................................................................................................... 18

Table 08: Mix Design of C30 ............................................................................................................... 19

Table 09: Specifications of steel bars ................................................................................................... 19

Table 10: Properties of Bentonite Fluid ................................................................................................ 20

Table 11: Specifications of BG Machines ............................................................................................ 20

Table 12: General details of Drilling Tools used at the site .................................................................. 21

1

1. Introduction Chapter 1

1.1. Company profile

Civil & Structural Engineering Consultants (Pvt).Ltd in Brief

Civil and Structural Engineering Consultants (Pvt).Ltd, more commonly known as ‘CSE

Consultants’ is a state of the art consultancy firm comprising some of the prominent Structural

Engineers in the industry and academia. CSE strives to maintain a high level of quality in its

services and aims to be the trend setter in the industry through innovation, state of the art

technologies and excellence in engineering. Being able to undertake well over 100 projects

within a short span since its establishment reflects the unmatched potential of the dynamic

team.

CSE is Honorary Chaired by Prof. Priyan Mendis; a world renowned Structural Engineer who

has been a consultant for many prestigious and landmark projects across the

globe including Burj Kalifa, the world’s tallest building. He is a former Discipline Head of

Civil Engineering at the Department of Infrastructure Engineering, University of Melbourne,

Australia.

The Managing Director Eng. Shiromal Fernando is one of the leading structural engineers in

Sri Lanka, who has been the Principal Structural Engineer for many high-rise

buildings including the tallest building in Sri Lanka. He is the present Country Representative

for ‘Council on Tall Buildings & Urban Habitat (CTBUH)’, the apex body of tall building

professionals across the globe & a Director at Green Building Council of Sri Lanka.

CSE is now engaged in some of the landmark projects in Sri Lanka and overseas. CSE strongly

intends to expand its services in the Civil and Structural Engineering and intends to be one of

the best engineering consortiums in the world and contribute to the development of the country

and world at large.

1.2. Company Vision

To be the resource and knowledge base in the field of Structural Engineering.

1.3. Mission

Maintaining professional standards for structural engineering, ensuring continued technical

excellence, advancing safety, creativity and innovation across the built environment and

promoting sustainable approaches in engineering solutions, supporting engineers as they

protect, influence and take forward our environment’s conservation responsibility.

2

1.4. Services

1. Structural Engineering Consultancy

2. Advanced Protective Technology for Engineering Structures

3. Green Consultancy

4. Other Services

Structural Engineering Consultancy

Structural Analysis and design

Modelling and Analysis of new designs – CSE provide structural analysis and

structural modelling with the use of advance structural analysis and design software.

The service will be provided as a whole project and also as a part of a project.

Structural Design – Being specialize in undertaking structural concrete and Structural

steel design CSE is always keen on providing a cost effective design for project

considering Financial, Economic, Environmental and Social Sustainability.

Structural Detailing

Structural Drafting

Seismic Design

Seismic evaluation

Seismic strengthening for existing structures

Investigation of Alteration & Failures

Additions and alteration to the existing buildings

Investigation of failures

Structural evaluation and remedial measures

Structural Audit Services

Design / peer reviews and certification – CSE holds expertise in providing excellent

Structural Audit Services. It is a preliminary technical survey that is efficiently carried

out by highly qualified engineers. The basic idea of this service is to assess the civil

engineering structure of buildings.

3

Ongoing & and Past Projects

CSEC Company has been under take so many projects in Sri Lanka. Some projects included

in below table.

Table 01: Project details

Project Location Situation

Lotus Tower:The lotus-shaped tower will be used

for communication, observation and other leisure

facilities

D.R Wijewardana Mawatha,

Colombo 10.

Under

Construction

Avic Astoria Residence: Proposed for Apartments,

hotels & Commercial Buildings

39,De

Mawatha,Kollupitiya,Colo

mbo03

Under

Construction

Proposed 40 storied 5 Star Deluxe Hotel and

Apartments for Lankem Ceylon PLC

Near Beira Lake Proposed

JKH Waterfront Resort

No. 130, Glennie Street,

Colombo 02.

Under

Construction

Altair Colombo

Sir James Pieris Mawatha,

Colombo 00200, Sri Lanka

Under

Construction

4

1. Training Experience Chapter 2

2.1. Training Experience in Lotus Tower Project over view-Lotus Tower

The Colombo Lotus Tower in the democratic socialist republic of Sri Lanka is located by the

lakeside of Beria Lake, with the height of 360m and the total building area of 2998m2, among

which the building area of tower base is 19461m2 and that of tower house is 7537m2 .The

whole structure of the tower consists of tower body (including tower foundation), tower base,

tower house and mast.

The tower body is cylindrical reinforce concrete structure with top elevation 263.100m and

the length of the mast is 86.900m, in which the concrete mast is 27.600m and steel mast is

59.300m.

The tower base is a frame structure with on floor under ground and three floors above

ground, which is built enclosing to tower body and is connected with tower base. The tower

house is an eight-floor steel frame structure over tower body. The whole tower structure is

attached to and supported by the tower body.

People who involved in to this project

Client: TELECOMMUNICATION REGURAROTY COMMISSION OF SRI LANKA

(TRCSL)

Figure 01: TRCSL Logo

Project Consultancy Unit: FACULTY OF ARCHITECTURE UNIVERSITY OF

MORATOWA

Figure 02: Moratuwa University Logo

Design & Built Contractor: CHINA ELECTRONICS IMPORT & EXPORT COPORATION

(CESC)

Figure 03: CEIEC Logo

5

Figure 04: Lotus Tower Figure 05: Front elevation of Lotus Tower

The elevation +/- 0.000 in this project is equivalent to the Sri Lanka elevation of 6.050m.

The designed reference period of structure is 50 years and the designed service life is

50 years, the load and seismic action is same with tower body.

6

2.1.1 Materials

Concrete

Supporting structure of tower house (inclined wall, inclined column 215.000m floor

structure)-C50

Beams and slabs of other parts-C35

Durability of concrete

1. The water-cement ratio should be less than 0.45

2. The maximum chloride content is 0.06%

3. The maximum alkaline content is 3.0 Kg/mm2

Mix design of Grade C50 Concrete

Table 02:C50 Mix Design

Designed Strength Grade C50

Required slump 220mm

Cement type Portland pozzolana Cement (P.P.C)

Manufacturer Holcim (Lanka) LTD

Maximum Aggregate Type 5-20mm

Admixture Name ART-JR2

Additive Name Fly Ash

Table 02: C50 Concrete Mixture Ratio

Strength Grade C35 Water-Binder

Ratio

0.40 Water-Cement

Ratio

0.40 Sand Ratio 50%

Material Cement Water Sand Aggregates Admixture Additive

5mm 20mm

Quantity 455Kgm-3 178Kgm-3 796Kgm-3 778Kgm-3 194Kgm-3 7.1Kgm-3 51Kgm-3

7

Steel

Reinforcement Details

Inner Tube

Table 03: Reinforcement details of Inner Tube

Figure 06: Reinforcement Diagram of Tower Body Inner Tube

Walls of Lift (Elevators) & Wall of Stair Case

Table 04: Reinforcement details of Walls of Lift (Elevators) & Wall of Stair Case

Figure 07: Walls of Lift (Elevators) & Wall of Stair Case

Elevation Wall

thickness

(mm)

Longitudinal

Reinforcement

Horizontal

Reinforcement

Wall

thickness

(mm)

Longitudinal

Reinforcement

Horizontal

Reinforcement

20.400-

253.800

200 14@150 14@150 250 16@150 14@150

Elevation External

Diameter(mm)

Thickness(mm) Longitudinal

Reinforcement

Circular Horizontal

Reinforcement

20.400-75.000 14500 350 20@150 16@150

8

Wall of Outer Tube

Table 05: Reinforcement details of Wall of Outer Tube

Figure 08: Reinforcement diagram of Outer Tube

Post-tension method in outer wall

Figure 09: Post-Tension Cables

Elevation Exte

rnal

Dia

mete

r(m

m)

Wall

thickness

(mm)

Petal

thickness

(mm)

Outer

longitudin

al

reinforcem

ent(1)

Inner

longitudin

al

reinforcem

ent(2)

Circular

Horizontal

Reinforcem

ent(3)

Additional

Horizontal

Reinforcem

ent(4)

Additional

Horizontal

Reinforcem

ent(5)

115.00-

195.000

1500

0

600 200 300Ф32@

155

300Ф32@

146

18@150 16@150 16@150

Post-tension cables covered with GI pipes

9

2.1.2. Equipment

Tower hoist

Figure 10: Tower Crane

The tower crane used for lifting heavy building materials like steel structures,

machinery equipment like power generators, wielding machines; and other objects

from the ground level.

Structural details

1. High of a truss shaped blocks-3m

2. Amount of steel jacks-6(recently)

3. Angle of Rotation-3600

4. Crane was balanced with counter concrete weights

Basic Components

1. The tower (the mast)-The tower, which gives the height to the crane.

2. The control room-the Operating mechanism is given to the tower crane.

3. Working Arm- It can extends horizontally carrying a trolley which runs in and out

of the crane’s center carrying the load.

4. Steel jacks-Used to stop waving due to wind.

Steel truss shaped jacks

Crane control room

Tower crane truss (shaped) blocks

Working Arm

Trolley

Hook Block

10

Concrete Vibrator

Figure 11: Concrete Vibrator

The concrete vibrator can released the trapped air & water and the concrete settles firmly in

place in the formwork so this help to consolidate freshly poured concrete.

Concrete Placing Boom

Figure 12: Concrete placing boom

A concrete placing boom was use at Lotus Tower construction to distribute fresh concrete

from ground level to upper level.

Concrete

distributing pumps

Compressor

11

Advantages

1. Easy to transport and set up

2. Secure handling & user friendly (handling by using the remote controller)

3. Grows upwards with the structure

4. Small space requirement

Specification

1. Model-Zoomlion HCG29A

2.1.3. Duties carried out in Lotus

Moisture Correction for C35 concrete mix designs

The Lotus Tower structure is being up with concrete, according to different concrete

mix designs & design specifications. Sand, aggregates, water, admixtures, additives

are the basic ingredients has been used for make Concrete mixtures and those

ingredients are available in this site.

Moisture was including in sand & aggregates due to current weather condition

surrounding the lotus tower site. The concrete is designed to with stand a certain

maximum load per area before failing known as compressive strength so, this

requirement is based on water-cement ratio. The water-cement ratio have to minimize

for establish to full fill this requirement by adjusting water amount (batch water +

moisture content in sand) as following procedure.

Step 1-collect sand & aggregates from the site.

Figure 13: Concrete Ingredients

Sand Aggregates

12

Step 2- Measured the weight of Sand& Aggregate samples.

Figure 14: Measuring scalar with wet sand sample

Step 3-Kept the samples on heating plate until release the moisture.

Figure 15: Heating the sample of aggregate & sand

Step 4-once again measured the weight of samples (dry) by using electronic weight scalar.

Figure 16: Measuring weights of dry samples

13

Calculation of C35 Concrete Mixture

Depending on site Condition a constant value is reduced from the moisture content. There for

the constant value obtained as 0.7.

Finding moisture content of sand

Wet weight of sand=346.8g

Dry weight of sand=324.7g

Moisture content=(346.8−324.7

324.7) ∗ 100

=6.8%

Finding moisture content of aggregates

Wet weight of sand=336.9g

Dry weight of sand=328.6g

Moisture content=(336.9−328.6

328.6) ∗ 100

=2.5%

Moisture correction

Weight of sand (According to C50 mix design) =887Kgm-3

Water content of sand =887∗(6.8−0.7)

100

=54.107Kgm-3

Sand adjustment

Weight of sand=887+54.107=941.107Kgm-3

Water adjustment

Weight of sand=183-54.107=129Kgm-3

Please refer the Original C35 Mix design which was attach to reference.

14

Pull out Test

This test was carried out for determining the pullout strength (the bond between concrete and

the steel bar) of hardened concrete or the structural strength of the anchoring system.

Equipment: Hydraulic Anchor Pull out Testing Kit

Figure 17: Hydraulic Anchor Pull Out Testing Kit

Procedure

Step 1-Insrted the disc in to test specimen (16mm steel bar).

Figure 18: Installing hydraulic disc in to steel bar

Step 2- An adjusted the gauge up to zero.

Figure 19: Adjusting gauge in to zero

15

Step 3-Applied the required force with the instrument to steel bar.

Figure 20: Appling pressure force

Results

Table 06: Results of tested specimen

Test specimen Anchorage length

(10*Rebar diameter)

Expected pressure

force value

Observed pressure

force value

16mm Rebar 160mm 43.2KN 50KN

The observed pressure force value (50KN) is grater then expected value (43.2KN). There for

anchoring system pass with the pull out test.

Survey at +15m level(Tower Roof)

Shrinkage of concrete is the time-dependent strain measured in an unloaded and unrestrained

specimen at constant temperature. There are so many shrinkages due to many reasons such as

plastic shrinkage, chemical shrinkage and drying shrinkage, but in this site only considering

about drying shrinkage and it is occurred due to the reduction in volume caused principally

by the loss of water during the drying process of poured concrete.

Therefore, a survey at level +15m was carried out to ensure the tower body is not undergone

a drying shrinkage due to above process.

Equipment: Level instrument & staff

Procedure

Step 1: Leveled the instrument and take took instrumental height by putting the staff at a

knowing Elevation (+14933mm).

Step 2: Took the staff and put it vertically on marked point which is in tower body wall.

Step 3: Took the level reading without changing the position of the instrument.

16

Calculations (e.g.)

Height of knowing point=14933mm

Instrumental height =2114mm

Height of marked point in tower body wall=1047mm

14933+2114=Z+1047

Z=16000mm

Expected Z value =16000mm

Observed Value =16000mm

There for no effect to tower body structure from drying shrinkage

+15m Level

Ground Level: +-0m

+14933mm

m

Auto Level

Staff Tower Body Wall

Z=16000mm

17

2.2. Training experience at Avic Astoria Residence

Project over view-Avic Astoria Residence

Project Details : Astoria Residential Development

Location : No. 418, R. A. De Mel Mawatha, Colombo 03

Client : Avic International Hotel Lanka Ltd,

No. 09, Deal Place, Colombo 03.

Figure 21: Client Logo

Structural Consultant : Civil & Structural Engineering Consultants (pvt) ltd

No. 64, Barnes Place, Colombo 7

Figure 22: Consultant Logo

Contractor : San piling (pvt) Ltd,

No. 295, Madampitiya Road, Colombo

Figure 23: Contractor Logo

Commencement : 04- Nov- 2014

Project Duration : 180 Calendar dates

Figure 24: Proposed Building

18

Project Location

Figure 25: Site Location

The project consists of basement(s) where basement floor level is approximately 6.0m below

ground level. In order to retain the surrounding earth, it has been selected contiguous piles for

the shoring works, by the structural engineer & according to the original design, the piling

scope of work is follows.

Table 07: Details of Structural Piles

Structural Piles

No. of piles

750mm Diameter (A) 4

900mm Diameter (B) 16

1200mm Diameter (C) 37

1800mm Diameter (D) 105

162

2.2.1. Materials

Concrete

General details

Concrete Grade : C30 at 28 days

Design Slump : 200 ± 25 mm

Cement Type : Holcim Extra (PPC)

Structural element : In-situ Bored Piles

Batching plant : City Concrete Ambatale

Construction site

19

Mix design

Table 08: Mix Design of C30

Element Quantity

Cement 429 Kg/m3

Sand 670.02 Kg/m3

Quarry Dust 290.59 Kg/m3

Coarse Aggregate 925.02 Kg/m3

Water 110.9 Kg/m3

Admixture: Hypecrete R 4700ml

Figure 26: Sample of C30 Concrete

Steel

Table 09: Specifications of steel bars

Figure 27: Steel Lot

Diameter

32mm 20mm 10mm

Grade RB500 RB500 RB500

Length 12m 12m 12m

Manufacturer MELWA MELWA MELWA

Type of use Reinforcement

Steel Bars

Reinforcement

Steel Bars

Reinforcement

Steel Bars

20

Bentonite

Table 10: Properties of Bentonite Fluid

Figure 28: Sample of Bentonite Fluid

2.2.2. Equipment

Rotary drill rig BG machine

Figure 29: BG 26 Machine

In this site there was 2 machines (BG 28 &BG26) available to use for drill pile holes

Table 11: Specifications of BG Machines

Type of use To displace the sand from bored pile

Ingredient water & bentonite powder

Properties Fresh unit Before

Concreting

unit

density 1.024-1.1 g/cm3 1.024-1.1 g/cm3

viscosity 32-50 S 32-50 s

Specifications

Machine Maximum

drilling

diameter

Maximum

drilling depth

height Power

BG 26 2200mm 65.4m 24.9m 224Kw@2100rpm

BG 28 2300mm 72m 24.194m 354 kW @1800rpm

Mast

Digital display

Rotary drive

Kinematic system

Kelly Bar

21

Drilling Tools

The rotary drilling tools provided as pre soil investigation reports and selected for usage

according to the soil conditions of this site. The rock auger used as a rotary tool for excavate

very hard layers working with dry condition. The tools provided with sufficient teeth and

with the boring working the sharpness of the teeth will reduced there for to maintain the

progress of this site the teeth are immediately replaced with new teeth.

Table 12: General details of Drilling Tools used at the site

Rock auger tool Core barrel

Main Application

Used to excavate hard rock layers.

Main Application

Used to cut through the rock layers.

Rock bucket Cleaning bucket

Main Application

Used for displace the soil & rock

pieces form pile hole.

Main Application

Used to clean bottom of the pile hole.

22

Crane Tremie pipes

Figure 30: Crane Figure 31: Tremie pipes

Excavator

Figure 32: Excavator

The main purpose is to backfilled with non-cohesive soil in to concreted piles.

Level instrument

Figure 33: Auto Level

Used to determine the casing top level & ground level.

Used to move heavy items such as Tremie

pipes, Diesel generators, wielding plants,

reinforcement cages etc. Transport them in

to another place.

Used to place fresh concrete,

smoothly in to pile holes.

23

Total station

Figure 34: Total Station

Used for surveying.

De-sander

Type of use: Separate the sand from bentonite fluid and distributed the bentonite fluid in to

silos for reuse to clean the pile holes.

Model: BE170

Figure 35: De-Sander (BE170)

Rebar Thread Rolling Machine

Figure 36: Rebar Thread Rolling Machine

Used for cut threads of steel bars.

Bentonite silos

De-sander

24

2.2.3. Summary of site work in Avic Astoria

Setting center points

Bored pile center location was set out by using total station equipment then offsets was

marked in 3 perpendicular directions at 620mm away from the center (if the pile was

1200mm diameter).

Figure 37: Setting out points

Temporary casing installation

After lay out pile center the temporary casing installed instable soil by using drilling rig BG

machine (in this site recommended to use 6m long casing.

Figure 38: Casing Installation

Checked the verticality of casing by using water level instrument & rechecked the

casing center coordinates

Figure 39: Checking Verticality of Casing Figure 40: Rechecking Casing Center

Coordinates

25

Boring work

Frist soil boring was done by using rock auger tool. then rock head is found tool has to

change to core barrel so by using core barrel drilled 1m length from rock head again tool has

to change to rock bucket for dis place the rock pieces .Finally above process continued until

met the bed rock layer (According to this site conditions and soil investigation results the

socketing length should be equal to 3*diameter of pile).

Figure 41: Boring Work

Cleaning the pile base

After completing the drilling work the bored pile has to clean by using de- sander (BE170) to

achieve this process they used bentonite chemical as a stabilizing fluid.

Figure 42: De Sanding Process

Installation of reinforcement cage

The reinforcement cage provided by according to drawings after assembled to its final length

the cage replaced in to pile hole by using the crane.

Figure 43: Installation of Reinforcement cage

26

Concreting the bored pile hole by using Tremie pipe method poured concrete in to

pile hole.

Figure 44: Installing Tremie pipe System in to Bored pile Figure 45: Concreting

Temporary casing removal

Rechecked the center casing coordinates and finally removed the temporary casing from the

concreted pile.

Figure 46: Casing Removal

27

2.2.4. Duties at Avic Astoria

Bentonite quality check

Purpose: To maintain the quality of bentonite fluid

Apparatus: Mud balance kit, Marsh funnel Cup & Stop watch

Procedure: For Density

Figure 47: Mud Balance Kit

Filled the cup with bentonite (make sure the instrument is thoroughly cleaned and

dry).

Figure 48: Filling Bentonite in to Cup

Kept the vent hole over the cup.

Figure 49: Closing cup with Vent Hole

Vent Hole

Linear

Gauge

Rider

Level Bubble

Fulcrum

28

Seated the instrument on the fulcrum and adjust the rider until beam is in balance (as

shown by the level bubble).

Figure 50: Seating Mud Balance on to Fulcrum

Finally obtained the reading for density value.

Figure 51: Density Reading

Procedure for viscosity check

Figure 52: Marsh Funnel with Cup

Marsh funnel

Cup

29

Cover the funnel orifice with finger and add freshly sample of bentonite in to marsh

funnel.

Figure 53: Filling Bentonite in to Marsh Funnel

Remove the finger and start stop watch and measure the time for fill bentonite fluid

up to marked on the cup.

Figure 54: Measuring time for fill the cup

Please refer the table 10 which is shown in page No.20 to see the bentonite quality

requirements.

PIT-pile integrity test

Date: 26th of November 2014

Location: Avic Astoria Residential Site

Purpose: To ensure there was no defects occurring in the bored pile

Apparatus: Hand held hammer, Sensitive accelerometer and pile integrity tester

Figure 55: Apparatus of PIT

Pile Integrity tester

Sensitive

accelerometer

Hand held hammer

30

Procedure

Step-1 Step-2

Figure 56: Clean the surface of the pile head Figure 57: Attach the Accelerometer

Step-3 Step-4

Figure 58: Tap the pile head with a hammer Figure 59: Record the wave Details

Test Results

900mm diameter (B1pile) 1200mm diameter (C1pile)

Figure 60: Test Result of 900mm Diameter Pile &1200mm Pile

Figure 60 Show PIT record of 900mm Diameter Pile &1200mm Pile with positive reflection at

the beginning, it should be noted as pile head, but in-between the pile head and the pile toe

wave varies with negative reflection. There for the pile integrity tester conformed those two

piles are not defective piles.

Pile Length

Signal

Magnification

Pile Head

31

Dynamic load test

Purpose: To evaluate the baring capacity and defamation of the C01 bored pile.

Apparatus: Guide Frame with Steel Hammer (2.5 Tons), Steel Weights (17.5 Tons)

Pile Dynamic Analyzer &Auto Level

Figure 61: Apparatus of Dynamic Pile Test

Precautions

Excavate the pile surrounding at least 1m length from pile top.

Protect the pile head by using steel casing.

Place a steel plate (about 50mm) on top of the pile head.

Figure 62: Pile Head Covered with a steel Casing

Steel Hammer

Steel Weights (17.5 Tons)

Steel Casing Guide Frame

Hydraulic Jack

Pile Dynamic Analyzer

Steel casing

32

Procedure

Measured the pile top level of C01 bored pile by using level instrument.

Figure 63: Measuring Staff reading

Installed the test weights (17.5 Tons) in to guide frame and attached the PDA gauges

on two opposite sides at 1m below the pile top.

Figure 64: Guide frame with Steel Loads

Increased the height of weights by 1500mm from pile top using hydraulic jack.

Figure 65: Lifting steel loads upward by using Hydraulic jack

33

Release the weights on to pile top without any force.

Figure 66: Releasing Loads in to Pile Top

Finally the PDA recorded the measurements and again measured the pile top level.

Figure 67: Measuring Results

Results

Figure 68: PDA Results

34

2.2.5. Problems encountered in Avic

Before washing a pile with bentonite Consultant have to check the bentonite quality

(viscosity & density) on this site the required viscosity range is 32 to 50 s & required

density range is 1.024-1.1 gcm-3 when checking a sample of bentonite the measured

viscosity value was in-between the range but the density of that sample was not in

above range there for Contactor had to add more bentonite powder with water to

overcome this problem.

When pouring C30 concrete into 1800mm diameter pile the reinforcement cage tends

to come upward due to the concrete pouring pressure, so that pressure created an

upward force on the reinforcement cage .So, immediately Contractor removed some

tremie pipes to overcome this problem.

35

3. Conclusion Chapter 3

The primary objective of this report is a description of practical knowledge. I attained on

construction site of an interchange structure during my summer internship training.

In the period of training, I closely studied the aspects of practical application of various

methodologies and learnt the art of being pioneer in solving practical problem faced at site;

during the course of my study I attained the following conclusions.

There are differences between theoretical and practical approach to execute various

construction process. Theoretical knowledge is insufficient to commence task at site.

The quality of construction work was at priority with respect to time. Various check

were formatted at each step of construction to ensure the quality of work.

The various factors such as climatic conditions, man power, availability of resources

and methods involved in construction plays a crucial role in an optimized completion

of project.

Contractor always were taken Safety measures to avoid injuries and accidents on site.

36

References http://csec.lk/about-us/

http://csec.lk/services/

http://csec.lk/projects/

Method statements of Sanpilling

http://www.bauerpileco.com/en/products/bauer_bg/bg_premium_line/bg_28_bs_80/

http://www.bauer.de/export/shared/pdf/bma/products/drilling_rigs/vl/BG_26_BT_70_

ValueLine_905-699-2.pdf

H.S. Thilakasiri, 2006,Interpretation of Pile Integrity Test (PIT) Results

H.S. Thilakasiri, R.M. Abeyasinghe & B.L.Tennakoon, by 2006 , Dyanamic Testing

of End Bearing Bored Piles in Sri Lanka

37

Appendices Location: Avic Astoria Residence

Calculating casing top level & ground level

Instruments: Level Instrument & staff

Procedure

Placed the staff on a known elevation point (in this Avic site there was 6 known

points) and hold it vertically to take the reading.

Then placed the staff on top of the pile head and take the reading.

Placed the staff on ground point to take the reading.

The mean sea level (M.S.L) is to be considered as zero.

Figure 69: Elevation Diagram

Calculation Made for B03 bored Pile (diameter 1200mm)

Staff reading of known point=851mm

Staff reading of casing top point=783mm

Staff reading of ground point=1350mm

Casing top level (C.T.L) =7805+851-783

=+7873mm

Ground level (G.L) =7805+851-1350

=+7306mm

Known point

Temporary

casing

Casing top

point

+7805mm

Staff

M.S.L:+-0

Auto level

Ground point

38

39