Pile Foundation FINAL

PILE Foundations

BORED PILE FOUNDATION

Step of Bored Pile Cycle time of each

step

( hour)

1. Set up location of

Bored Pile

0.3

2. Inserting Casing 2

3. Drilling 8

4. Removing slime

1

5. KODEN Test

1

6. Inserting Steel

Cage

2

7. Inserting Tremie

Pipe

1

8. Pouring the

concrete

2

9. Remove casing 1.5

Total Cycle Time 18.8

Bored Pile Procedure :

1. Set up the Location of Bored

Pile

2. Insert Casing

3. Drilling

4. Removing Slime

5. KODEN-Test

6. Insert of Steel Cage

7. Insert Tremie Pipe

8. Pouring the Concrete

9. Removing Casing

10. Covering of Expose

Concrete with a Pile Cap


Total Station instrument are used to survey each pile point.


Insert casing

casing must be stand vertical

by checking verticality of casing when insert casing


use Vibrodriver or Vibrohamer to insert casing


Drilling

Drilling Machine :

weight : 130tons

BG - 40 drilling depth : 49m

diameter : 3m

weight : 96tons

BG - 28 drilling depth : 39m

diameter : 2.5m

weight : 91tons

SD - 515 drilling depth : 36m

diameter : 2.5m

BG - 40

BG - 28

SD - 515


Removing slime

when finish drilling , we use Mechanical pump equipment to remove slime .


5. KODEN Test

KODEN test utilizes the principle of ultrasonic wave travel from sensor to the wall of drilled hole and reflect to the sensor through the Bentonite slurry.

Equipment KODEN equipment consists of two parts, recorder unit and winch unit .

Recorder Unit Winch Unit


Recorder unit controls the operation and record the test result. On the other hand, winch unit lowers the probe (sensor) down the hole for ultrasonic reflection .

Testing Procedure

1. Remove any obstacle around the hole area in order that the test equipment can access to the hole .

2. Place the winch unit over the top of drilled hole or on the steel casing. Position the sensor (probe) at the center of the hole .

3. Lower the sensor into Bentonite slurry. Hold the sensor at depth approximately 1 to 1.5m .

4. Restore the sensor to the starting position and perform the test.


Test Result

Test results are presented in graphical plot and show characteristics

below :

1. Profile along two perpendicular axes.

2. Average verticality of the hole.

3. Location or depth where abnormality

Occurs such as reduction in diameter,

or collapsed wall of the hole.

4. Depth of drilled hole.


Insert of steel cage


Insert Tremie

Type of tremie pipe :

We have 3 types of tremie : 1m, 2m and 3m

Length


How to insert tremie pipe :

1. Use mobile crane to hang the hopper

2. Then connect each tremie pipe

3. After that put it into the bored pile

hole

until bottom

When we pour concrete, we have to bury

the tremie pipe into concrete as below :

Diameter of Bored

Pile

Buried Length of

Tremie

1000 3 to 3.5m

1800 2 to 2.5m


Pouring the concrete

Quality of Concrete :

Max. size of Aggregate : 2.5cm Workability : 55cm ( Flow )


Strength of concrete :

Design strength : fck =300kg/cm ( 28days cure concrete )

Material Strength

Calculation of fck ( Mpa ) Strength of mix ( Mpa )

Target Strength 21 > fck fck + 7

( Standard specifications of concrete ) 21 fck 35 fck + 8.5

Strength of mix ( Target Strength )

So, for Actual Concrete

Strength : 400kg/cm

fck 300kg/cm = 29.42 Mpa

Strength of mix

29.42 Mpa + 8.5 Mpa = 37.92 Mpa = 389

kg/cm

Apply : 400 kg/cm


Remove casing

CASE STUDY - BORED PILE FOUNDATION IN METRO


Current METRO piling work at Ashram


Reinforcement Cage for Pile cap

DIAPHRAGM WALLS

Diaphragm Walls are particularly well suited to large open sites with deep

excavations;

they are most commonly built as cast in situ walls and have installed

thicknesses ranging from 500mm to 1500mm.

Cast in situ diaphragm walls are constructed as a series of primary and

secondary panels varying in length from 2.8m to 7.5m to accommodate the

geometry of the wall.

Although shallower walls

probably account for the

majority of diaphragm walls

installed;

wall depths over 25 meters

are almost the exclusive

preserve of the system.

DIAPHRAGM WALLS

Construction Sequence of

Diaphragm wall

Fixing of Alignment

Stage-2: Guide wall Construction

Stage-3: Trenching

Stage-4: Trench Cleaning

Stage-5: Stop ends fixing

Stage-6: Reinforcement Cage

lowering

Stage-7: Placing of Concrete

Stage-8: Withdrawal of Stop ends

DIAPHRAGM WALLS

Where are wall pre-cast diaphragm walls used?

Diaphragm Walls provide a very stiff, strong and cost effective solution for the construction of permanent retaining walls and shaft walls. This method of wall construction delivers far fewer construction joints than

alternative systems such as bored pile or sheet pile walls.

Applications for diaphragm walls include: retaining walls for deep basement excavations, cut-off barriers, retaining walls for cut and cover tunnels, quay walls and shaft walls.

DIAPHRAGM WALLS

CASE STUDY - DIAPHRAGM WALLS IN METRO

Level of the bentonite slurry should be maintained

preferably at least 1.5m above the ground water level

to avoid problem of instability.

Density and Viscosity of supporting fluid

Loss of shear strength with time

Suction effect during trenching

Specification of Bentonite (as per IS:2911-Part1:Sec2

Liquid limit : 300 to 450 % (in accordance with IS:2720-

part V)

Sand content : Less than 7 %

Density: 1.12

Marsh viscosity : About 37 second, tested by Marsh

cone

Swelling index: Swelling index at least 2 times of dry

volume.

pH value : Less than 11.5

Tests and compliance values for support fluid prepared

from bentonite (as per IS9556-1980)

CASE STUDY - DIAPHRAGM WALLS IN METRO

THANK YOU

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