Pile Foundations 1

Foundation Engineering

Kaniraj Shenbaga

Universiti Malaysia Sarawak

Date: 24 November 2012 (Saturday)

Time: 7.45 am

Pick up venue: FK LG Lobby Area

Place of visit: Batang Sadong bridge construction site

Students should wear protective footwear and should take all

safety precautions at the site. Students should stay within the

place they are allowed to visit.

Students need to submit a site visit report. They should use

their individual log book for recording observations. However,

the site visit report is a group report.

Site Visit

Cover page with details of group members

Aim of the site visit

Description of the project and site

Observations at the site relevant to the course objectives

of Foundation Engineering

Conclusions including the usefulness of the site visit

Relevant photographs with appropriate caption

Explanation of the contribution made by each member of

the group to the report

Typical Contents of Site Visit Report

The report is a group report. The groups are the same as for the

laboratory reports.

Use 25 mm margin all around, Times New Roman 12pt size font,

and 1.15 spacing.

The report should not exceed 5 pages excluding the cover page

and contribution page.

Submit the reports Dr Kanirajs mail box before 12 noon on 10

December 2012.

The marks for the site visit report are 10.

Plagiarism will be viewed seriously.

Site Visit Report

Pile Foundations

Categorize different types of deep

foundations in sand and clay and

calculate their vertical load carrying

capacity.

Learning Objective 3

Methods & Applications Different types of piles and their methods of

construction

Load Capacity Determination of load carrying capacity of single piles.

Structural capacity

Compressive load, uplift load and lateral load

capacities

Topics on Pile Foundations

Pile Groups

Determination of load carrying

capacity and settlement of pile group

Pile Caps

Procedures of structural design of

pile caps

Topics on Pile Foundations

Types of Foundations

D = Depth, B = Breadth or width

D/B 1. e.g. Footings, Raft foundation

Shallow Foundations

GL

B

D

D

L

Shallow foundation

Pile foundation

Soil

Deep Foundations

D/B > 1

1 L/D 15.

Moderately deep

foundations

L/D 15. Deep

foundations. e.g.

Pile foundation

GL

B

D

D

L

Shallow foundation

Pile foundation D = diameter or breadth

L = length of embedment

Soil

GL

Pile

Piles

Pile cap

Piles are columnar structures buried within soil.

Types of Foundations

Shallow foundations D/B 1. e.g. Footings,

Mat/raft foundation.

Deep foundations D/B > 1. 1 L/D 15. Moderately

deep foundations

L/D 15. Deep

foundations. e.g. Pile foundation

GL

B

D

D

L

Shallow foundation

Pile foundation

Shallow foundation: B = breadth or width; D = depth

Deep foundation: D = diameter or breadth; L = length of embedment

Shallow Foundations Deep Foundations

D/B 1 L/D > 15

Construction is visible Construction is invisible

Load is transferred directly

on the soil

Load is transferred through

surface and tip

Less skill required Special equipment and skill

required

Inexpensive Expensive

Shallow Vs. Deep Foundations

Timber Piles

http://www.123rf.com/photo_5972425_closeup-of-pile-of-

logs-showing-tree-rings-in-cross-sections.html

http://www.shutterstock.com/pic-699138/stock-photo-close-up-of-a-pile-of-

lumber-from-the-cross-section-building-material-at-a-construction-site.html

Precast Concrete Piles

Square pile Octagonal pile

Steel Piles

Hollow tube plies H-section plies

http://image.made-in-china.com/2f0j00YMdahIqAfbpK/Steel-Pile-Seagull.jpg

Situations where pile foundations are needed

A hard stratum

underlies soft soil.

Pile is resting on the

hard stratum. Load is

transferred to the

hard stratum. This is

an end bearing pile. http://www.crazyengineers.com/forum/civil-structural-engineering/41286-pile-foundations.html


Soil is soft and

deep. Pile transfers

the load to the soft

soil. This is a

friction pile.

http://accessscience.com/content/Pile%20foundation/516900


Uplift or tensile load

acts on the foundation.

Shallow foundation has

limited or low uplift

load capacity.

Therefore, pile

foundation is used.

http://www.ustudy.in/node/2735


Lateral load acts on

the foundation.

Shallow foundation

has limited or low

lateral load capacity.

Therefore, pile

foundation is used.

Pile

Soil

Horizontal load

Soil reaction

Pile


Vertical and battered

(inclined) piles are

used to resist

combined uplift and

lateral loads, and

moment acting on

the foundation.

Soil

Earth pressure

Retaining wall

Batter piles

GL


Large areas

exposed to wind

load transmit high

moment to the

foundation.

Therefore, they are

supported by piles.

Large surface area

Piles


Soil below the

foundation may be

removed by the

water current (scour).

Requires piles to

transfer the load

below the scour zone. Piles

Pier

River

Soil

Piles

Bridge pier

Pile cap

http://tn.water.usgs.gov/pubs/FHWA-RD-97-028/effepier.htm


Loose saturated sand

layers near the ground

surface may liquefy

during earthquake.

Piles are required to

transfer the load into

the zone below.

Loose saturated sand

Zone not susceptible to liquefaction

http://www.ce.washington.edu/~liquefaction/selectpiclique/nigata64/tiltedbuilding.jpg

Liquefaction failures Niigata Earthquake 1964

http://www.nishimatsu.co.jp/eng/ar2008/contents/Photo/Photo_21.html


Pile foundations

are often used as

fender systems to

protect bridge

piers from vessel

impact. Fender piles

Vessel


In urban areas, pile

foundations may

be required if deep

excavations are

anticipated nearby.

Present construction

http://www.foundationspecialists.com/Default.aspx?tabid=5536&id=Causes%20of%20Foundation%20Movement

Soil swelling Soil shrinking Up and down movement due to swelling and shrinking of soil damages the buildings. Pile foundation prevents the damage.


In expansive soils,

pile foundations

are required to

support the

structure in the

stable zone.

Pile

Pile Installation

Driven Pre-Cast Piles

Houses in Miri, Sarawak

Pre-cast concrete piles

Pile driving rig

Hammer

Piles stacking arrangement

Lifting hooks

Pile end to receive pins

Pile end - Pin

Marking pile locations on the ground

Hooking the pile

Lifting the pile

Lifting the pile

Pile helmet

Beginning pile driving

Pile driving in progress

Attaching the follower

Driving near completion

Driving the follower

Controlling pile driving

Formwork and reinforcement for pile cap

Concreted pile cap

Pile cap ready for construction of column

Ready to level the site

Installation of Piles

Cast-in-situ Piles

Driven Cast-in-situ Concrete Pile

Driven Cast-in-situ Concrete Pile

1 2: Driving hollow casing

pipe (with closed end at the

bottom) into the soil

3: Pouring concrete into

the pipe to some depth

4 5: Lifting the casing up

and driving it down to form

a bulb at the tip

6: Filling concrete inside

the casing pipe up to the

top

7: Pushing the

reinforcement cage into

concrete

8: Completion of

installation of pile

Bored Cast-in-situ Concrete Pile

http://www.n-sharyo.co.jp/business/kiden_e/earthdril.html

Bored Cast-in-situ Concrete Pile

1 2 3: Installation of a

short guide casing

4 5: Drilling below casing

using bentonite slurry to

support the borehole

6 7 8: Forming a bell at

the bottom using under-

reaming tool

9 10 11 12: Inserting

reinforcement cage and

tremie concreting under

water

13 14: Removal of guide

casing at the top and

completion of pile

installation

Driven Cast-in-situ Shell Pile

Driven Cast-in-situ

Shell Pile

http://www.geoforum.com/info/pileinfo/images/west2.jpg

Driven Cast-in-situ

Shell Pile

1. Placing assembled shell pile sections with

pile shoe and driving mandrel on the ground

2. Driving shell pile sections into the ground

3. Removing mandrel

4. Placing reinforcement cage and concreting

5. Completion of installation of pile

Driven Cast-in-situ Shell Pile

Classification of Piles

Based on material

Timber pile for light loads

Concrete pile for heavy loads

Steel pile for very heavy loads

Composite pile for very heavy loads

Based on method of construction

Precast pile, Cast-in-situ pile

Driven pile, Bored pile, Jacked pile


Based on method of load transfer

Friction pile load transmitted mainly by skin friction

End bearing pile load transmitted mainly by point

bearing

Based on use

Load bearing pile used for transferring load

Uplift pile used for transferring uplift load

Compaction pile used for densifying the soil


Based on influence of construction of

pile on the soil and pore water pressure

in the soil

Displacement pile

Non-displacement pile

Small displacement pile


Construction of pile displaces and

disturbs the soil around the pile

significantly. e.g. driven precast pile,

driven closed ended tube pile

Displacement Pile

Construction of pile has no significant

influence on the soil surrounding the

pile. e.g. bored piles

Non-displacement Pile

Construction of pile has small

influence on the soil surrounding the

pile. e.g. driven H-pile, driven open

ended pipe pile

Small Displacement Pile

Factors in Selection of Pile Type

Nature of load transmitted

- light/heavy/very heavy load

- compressive/uplift/lateral load

Location of site

- presence of nearby structures

Ground conditions

- ground slope

- accessibility of the site


Durability

- presence of living organism

- pH of soil

- presence of sulphate in soil

- wave action

Contractors past experience

- past performance

- available resources


Pile Foundations 1

Documents

Transcript of Pile Foundations 1