2. • Introduction and Terms related to Piles
• Classification of Piles
• Load Bearing Piles and its types
• Driving Load Bearing Pile
• Ancillary Concepts
• Diaphragm Walls
3. • Foundations used – Constraints like Large Design Loads,
Poor Soil at Shallow Depths, Property Line Constraints,
etc.
• System used for other purposes like Coffer Dams and
Bulk Heads
• Scope: Selection of Piles, Equipments used for driving,
ancillary concepts
• Can be classified on several basis, scope; on the basis of
use and materials
4. Sr.
No.
Term Description
1. Butt Upper end of the driven pile
2. Cushion Material inserted between the ram of the hammer
and driving cap
3. Cutoff Portion of pile removed from upper end of the pile
after driving
4. Driving Cap Cover placed over the butt
5. Embedment Length of the pile from G.L. to its tip
6. Penetration Axial movement of the pile per hammer blow
7. Pile bent Two or more piles driven together fastened with
bracings
8. Tip Lower end of the pile
9. Shoe Metal portion attached to the tip
10. Overdriving Driving such that damage is caused to the pile
5.
6. • Used to transmit structural loads to the hard stratum
• Suitable when shallow foundations are not feasible due
to various constraints
• Classified on the basis of material, method of
constructing and method of driving
Sr. No. Type of Pile Sub Classification
1. Timber (a) Treated
(b) Untreated
2. Concrete (a) Precast – Pre stressed
(b) Cast in Situ with shells
(c) Augered Cast in Situ
3. Steel (a) H section
(b) Steel Pipe
4. Composite (a) Concrete and Steel
(b) Plastic with steel pipe
core
7. 1. Timber Piles
• Made of trunk of trees, generally available in lengths 15
to 45 feet, design loads are 10 to 60 tons
• Timber; Susceptible to decay and hence the use of
treated timber
• Preservative such as salts and creosote used to reduce
the rate of decay
• Untreated timber; Lesser life, used for temporary
construction Quality Control
1. Check for minimum nominal circumference
2. Check for straightness
3. Check for Knots
8. 2. Concrete Piles
• In general, can be either
precast – pre stressed or cast
in situ
• P-P piles shapes: square,
cylindrical or octagonal
• Square and octagonal are
casted in horizontal forms, on
casting bed
• Cylindrical are casted in
cylindrical forms and spun for
consolidation
• Steam Curing is done for the
above, pre stressing done with
strands, spiral reinforcements
are provided
• Drawback: Reducing or
increasing the length of piles,
upon any requirement
9. • It is advisable to use rammer with heavy ram and low
impact velocity when soft soils are encountered
• Driving cap should fit loosely around the top of the pile –
prevention of torsional stresses
• Ends of the pre stressing strand or reinforcing must either
be cut off flush with the top of the pile or the driving cap
must be designed to contain threads
• To eliminate eccentricity, top must be perpendicular to the
longitudinal axis
• It is important to avoid soil plug in case of cylindrical piles
for structural stability reasons
10. • Cast in situ piles can be constructed in two fashions; by
displacing the surrounding soil or by not displacing the
surrounding soil
• First can be performed in two ways; concrete placed in
hole previously driven in the ground or concrete placed in
hole from which mandrel is removed
• Franki technique is a patented technique to perform the
first
• Second is consonance with augered cast in situ piles
• ACIS piles are constructed by rotating a hollow shaft
continuous flight auger into soil to a predetermined tip
elevation
11. 3. Steel Piles
• Have higher initial costs, but lower
driving costs
• Used when piles are to be driven to
greater depths, strength required is
high and less displacement of the
surrounding soil
• Can be of two types; H section or steel
pipe piles
• H section is primarily used as end
bearing pile, susceptible to deflection
on striking boulders or other obstruction
• Used in the urban areas where heaving
of surrounding soil may become a
problem
• Available in small lengths where height
or head room is not enough for driving,
small lengths are welded together
12. • Steel pipe piles can be hollow box or tubular in shape
• Most efficient friction piles
• Can be close ended or open ended
• Close ended are driven by conventional methods and
sections are joined with the help of internal sleeve
• Open ended are driven in the soil and the soil inside is
removed by methods like bursts of compressed air,
mixture of water and compressed or use of earth auger
13. 4. Composite Piles
• Used in some special situations
• Special situations; hard driving conditions or warm marine
conditions
• Can be of the types; concrete steel composite, steel concrete
composite and plastic steel composite
• Concrete steel composite; top portion of pre stressed concrete
pile, and tip would be a steel H pile, suitable for marine
conditions
• Steel concrete composite; Steel casing with hollow spun
concrete core, resting on solid driving shoe, suitable for hard
driving conditions
• Plastic steel composite; replaced creosote coating, Plastic
piles consisting of steel hollow core, most suitable for fender
14. • Total resistance offered by the pile is the sum of forces
produced by friction and end bearing
• Representative value for skin friction can be obtained by
determining the total force required to cause small
increments
• The magnitude of end bearing is determined by driving
button bottom pile test
• For large scale projects – test pile program should be
conducted – cost effective
• Factors when selecting a method for driving piles; size
and weight of pile, driving resistance, available space,
noise restrictions
15. • Initial site investigations give
information on soil characteristics and
depths of strata capable of supporting
the load.
• Used to arrive at more precise pile
length and number of blows per foot by
the hammer to attain desired bearing
capacity
• Test piles are selected, which have
length larger than predicted by borings
for some reasons
• Static loads are applied by methods;
static test weights or reaction pile
method
• Static test weights are incrementally
applied on the pile and relevant
information is gathered
• Reaction pile method consists of steel
H piles, placed in close proximity of the
test pile and consequent gathering of
16. • For driving piles, many types of
hammers are used, these are
used to furnish energy required
to drive pile, various types are
as follows:
1. Drop hammer
2. Single acting
steam/compressed air
hammer
3. Double acting steam
/compressed air hammer
4. Differential acting
steam/compressed air
hammer
5. Diesel hammer
6. Hydraulic impact hammer
7. Vibratory drivers
17. • Several factors influence selection of piles; size and type
of pile, number of piles, character of soil, location of
project, topography of site, type of rig available, land or
water
• Hammer should be selected such that there is minimum
practical cost
• In general, it is sensible to select largest hammer that
can be used without overstressing
• Considerations must be specially given to crane
18. • Method necessary to
position the piles at proper
location with required
alignment or batter that will
support the pile during
driving
• Following methods are used
for said purpose:
1. Fixed Leads
2. Swing Leads
3. Hydraulic Leads
4. Templates
• Other methods are
1. Jetting Piles
2. Spudding and Preaugering
19. • Diaphragm walls are underground
structural elements commonly used for
retention systems and permanent
foundation walls.
• Diaphragm walls provide a water tight
barrier and are constructed with a
minimum back slope subsidence.
• They are formed from reinforced
concrete and are constructed as normal
cast-in-place walls with support, which
become part of the main structure.
• They can also be used as deep
groundwater barriers.
20. • Can be installed through
virtually all soil conditions, to
any plan geometry and to
considerable depths.
• Can be constructed ahead of
time and independent of other
site activities.
• Can be constructed in relatively
low headroom and in areas of
restricted access walls can be
quickly formed several hundred
feet deep and through rock,
with good control over
geometry and continuity.
• They are relatively costly.
• They are also unsuited to
strong soils conditions where
penetration is slow and difficult
due to the use of the slurry
trench method.
21. • As permanent and temporary foundation walls for deep
basements.
• In earth retention schemes for highway and tunnel
projects.
• As permanent walls for deep shafts for tunnel access.
• As permanent cut-off walls through the core of earth
dams.
• In congested areas for retention systems and permanent
foundation walls.
• Deep ground water barriers through and under dams.
22. • The panel dimensions 50 to 100 cm thick and up to 7m
height, extending to the excavation bottom.
• The installation starts with the construction of shallow
concrete or steel guide walls.
• The excavation is then made using special equipment, such
as the thin-grab clamshell.
• Bentonite slurry is then pumped into the trench to provide
temporary support and a prefabricated reinforcing cage is
lowered in.
• The bentonite slurry is then replaced by concrete and the
sequence proceeds onto the next panel.
23. • Construction Planning, Equipments and Methods by
Puerifoy, Schexnayder & Shapira
• Soil Mechanics and Foundations by Dr. B. C. Punmia &
Ashok Kumar Jain
• http://en.wikipedia.org/wiki/Deep_foundation
• www.franki.co.gg/
• Selecting Pile Construction Method using Fuzzy
approach, Zayed, T. M., Journal of Construction
Engineering and Management, ASCE.
