AHSANULLAH UNIVERSITY OF SCIENCE AND TECHNOLOGY

WELCOME TO OUR PRESENTATION

DEPARTMENT OF CIVIL ENGINEERING

GROUP NO-1

WE THE GROUP MEMBERS:• MD. BULBUL AHMED 10.01.03.003• MD.SHARIFUL ISLAM 10.01.03.008• MD.YOUSUF BIN AZIZ 10.01.03.018• ABU SAYED MD.TARIN 10.01.03.020• MD.FARHAN ABIR 10.01.03.026• MD.SABBIR KARIM 10.01.03.037• MD.YASIN 10.01.03.038• MD.EZAZ AHMED 10.01.03.041• S.M.RAHAT RAHMAN 10.01.03.044• MD.ABU RAIHAN 10.01.03.049

DEEP FOUNDATIONSABBIR

RAHAT

RAIHAN

FARHAN

BULBUL

YASIN

OUR TOPIC IS

Deep Foundation

Foundation: Foundation is the lowest and

supporting layer of a structure.

Geotechnical engineers design foundations based on the load characteristics of the structure.

FOUNDATION

DEEP FOUNDATION SHALLOW FOUNDATION

The most common forms of construction pertaining to deep foundation are :

PILES PIERS CAISSONS

Shallow Foundation

RAFT FOUNDATION

Deep Foundation

CAST IN SITU PILE PRECAST PILE

PILES

CAISSONS

PIERS

Classification of Piles

Depending upon materials used in their manufacture, piles can be classified as :

a) Concrete Piles

i) Cast-In-Place or cast-in-situ Piles

ii) Pre-cast Piles

iii) Pre-stressed concrete Piles

b) Steel Piles

c) Timber Piles

d) Composite Piles

DIFFERENT TYPES OF PILES

PRECAST PILE

Definition & Explanation

PRE-CAST PILE: Pre means before & cast means made. So precast pile refers to a pile that

has made before it is being used.

PRECAST PILE

Why and Where it is used?

• Pre cast pile is used for extra heavy weight structure because it can ensure full strength by proper maintaining.

• It can be used under water.• There is no possibility of the reinforcements

getting displaced. • There is no possibility of the voids being left.• Not to attack by corrosive constituents in the

soil and the sub-soil water.

SHAPES OF PRE-CAST PILES

HEXAGONAL

CIRCULAR

RECTANGULAR

DESIGN OF PRECAST PILE

Structure of Precast pile & Related Information

• By the soil test, we would be find the depth of penetrate.• By which length of a pile can be determined.• After determine the total weight of the building, we would

find the number of piles. • The diameter of the pile normally varies from 35 cm to 65 cm

and their length varies from 20 ft to 30 ft.• Besides bearing load for easy transportation & movement big

weir or reinforcement is used in the pre cast pile.• For easy driven rectangular pile is often made.

• Longitudinal reinforcement usually consists of one bar 20 mm to 50mm in diameter at each angle of the section of the pile.

• The vertical rods are tied horizontally by bars 6mm to 10mm in diameter.

• The horizontal bars may be provided in the form of stirrups wound around the verticals.

• Pile shoe & pile stirrup is used in the lower part of the pile to

driven the pile easily.

CASING

SOIL CONDITION

Soil suitability• Suitable in a wide

range of soil conditions• Working loads in excess

of 1000kN• Useful for very deep

piling upto 40 m• In soft ground or in

aggressive or contaminated soils

Bearing Capacity• High bearing capacity• Concrete formations

around the contracted sections increase the capacity.

• Compact soil & increase the bearing capacity

Process of Precast pile

• Steel form is used for the precast pile manufacture.

• Before pore the concrete in to the form, Mobil or other kind of oil have been used.

• cement, sand ,aggregate ratio is normally 1:2:4 in pre cast pile.

• But to make the foundation stronger mix ratio is used 1:1.5:3

• When the concrete pore in the steel form it would be ramming by the vibrator.

Picture of Processing Precast pilePicture of Processing Precast pile

Curing & Driving

• After 3 days, pile have been covering by the sheet.

• After 3 days of casting, steel form would be removed.

• Then the piles would be prepare for 4 weeks curing.

• Then the piles are transported to the site for driving

Picture of CuringPicture of Curing

Picture of DrivingPicture of Driving

Advantages of Precast Pile

• Cast well before work.• Well supervised• Reinforcement remain in their proper position• Can be driven under water• After driven they can be loaded soon• We can get required strength• Detect the damage before use• Properly cured by water

Disadvantages of Precast Pile

• Difficult to manufacture• Not economical• Subject to longitudinal and transverse cracking• Not aesthetic• Not appropriate for curved or flared structures• Complicated for skews

Reinforcement of the Site

• Main rod 22 mm diameter• Stirrup 10 mm diameter 60 grade• Spacing on stirrup 4”~6”~4”• Some extra16 mm rod was provide in both two end due

to pressure• extra rod length is 3.5’ • Clear cover 2’’ for subsurface• Stirrup hook bend at 135 degree & bending portion is

3’’ long Steel shuttering• Triangle pile shoe was set in the bottom of the pile

Difference of Theoretical & Practical

Theoretical

• We can joint two pile

together

• Maximum length 40 ft

• All of the test have to

done before use

Practical

• We use one pile to

drive.

• They use 50~55 ft pile

• They only do some test

in site

Cast In Situ Pile

WHAT IS CAST-IN-SITU PILES?

•Cast in situ piles are those piles which are

cast in position in side the ground.

•Reinforcements are necessary to be provided

in a cast in situ Piles , when the pile acts as a

column and is subjected to a lateral force.

WHAT IS CAST-IN-SITU PILES?

PURPOSE OF CAST-IN-SITU PILE

• Load Transmission• Load Resistance

TYPES OF CAST IN SITU PILES

SIMPLEX PILE FRANKI PILE

TYPES OF CAST IN SITU PILESVIBRO PILE VIBRO EXPANDED PILE

TYPES OF CAST IN SITU PILES

RAYMOND PILE MAC ARTHUR PILE

CONSTRUCTION PROCEDURE OF CAST IN SITU PILE

LOOSANING OF SOIL

I. Cutting and Scraping Boring Grab Cutting Teeth For Rotary Drilling ii. Ripping iii. Percussion

REMOVAL OF SOIL

Intermittent Transport• Rope Grab• Rotary Drill

CONTINUOUS TRANSPORT

• Flush Drilling• Continuous Auger

TEMPORARY SUPPORT

Drill Casing• Vibrating• Oscillating• Rotating

DRILLING MUD

• Water• Bentonite• Polymer

ENLARGED BASE

• Under reaming• Grouting• Plug Expulsion

CASTING Of Pile

ReinforcementConcrete

MixCasting of Concrete

BORING PROCESS

Choice of place and boring machine

FIELD TANK AND REMOVAL OF OVERFLOWING WATER

THE PROCESS OF CASTING

Insertion of temporary casing with shoe

THE PROCESS OF CASTING

Placement of reinforcement

THE PROCESS OF CASTING

CASTING OF CONCRETE

THE PROCESS OF CASTING

CASTING OF CONCRETE

THE PROCESS OF CASTING

Removal of temporary tube and finish of casting

COMPARISON BETWEEN THEORY AND PRACTICAL FIELD

Theoretically Practical Field

• Pouring of Concrete and Withdrawing of steel tube gradually

• Polymer, Bentonite, or Steel Case is used

• Auger or rotary drill is used

• Steel tube is withdrawn after 28 days

• Only Bentonite solution is used

• Only Rotary drill is used

DIFFICULTIES OF PILEING AND HOW TO OVERCOME THIS

PROBLEM SOLUTION

• Rocky layer of soil with stone

• Rising water from the bottom of hole

• Corrosion can be occurred

• Abort drilling• Pump the water.

Best, use precast pile• Soil test is needed.

Corrosion resistant cement

ADVANTAGES OF CAST-IN-SITU PILES

• Cannot be used under water• Displacement of reinforced• Dumping of concrete from a great height• Inspection is not possible; voids may be left• Contact of water of concrete to the dry soil if uncased• Freshly laid concrete is susceptible to soil components• Driving of adjacent piles may rupture shell-less cast-in-

situ pile

• Cannot be used under water• Displacement of reinforced• Dumping of concrete from a great height• Inspection is not possible; voids may be left• Contact of water of concrete to the dry soil if uncased• Freshly laid concrete is susceptible to soil components• Driving of adjacent piles may rupture shell-less cast-in-

situ pile

DISADVANTAGES OF CAST-IN-SITU PILES

ANY QUERY ???

THANK YOU