3. When the depth of foundation is more then the width of foundation ,then it
is termed as deep foundation.
The deep foundations are classified as below:
Pile foundation Cofferdams Caissons
Pile foundations are used extensively for the support of buildings,
bridges, and other structures to safely transfer structural loads to the
ground and to avoid excess settlement or lateral movement. They are
very effective in transferring structural loads through weak or
compressible soil layers into the more competent soils and rocks below.
4. SITUATIONS WHERE A DEEP FOUNDATION IS NEEDED:
All the above schematics show the various type of piles
foundation and load carry of them.
5. It is used;
1.where the soil is compressible,
2.where the soil is water logged and
3.when stratum of required bearing
capacity is at greater depth.
The major uses of piles:
To carry vertical compression loads,
To resist uplift loads
To resist horizontal or inclined loads
7. • Nature of structure
• Loading conditions
• Availability of funds
• Availability of materials and equipments
• Types of soil and its properties
• Ground water table
• Self weight of pile
• Durability of pile
• Cost of pile
• Maintenance cost
• Length of pile required
• Number of piles required
• Facilities available for pile driving
• Presence of acids and other materials in the soil that would injure the
8. Based on the function
1. End bearing Pile
2. Friction Pile
3. Compaction Pile
4. Tension Pile or Uplift Pile
5. Anchor Pile
6. Fender Pile and Dolphins
7. Batter Pile
8. Sheet Pile
Based on the material & composition
1. Concrete Pile
2. Timber Pile
3. Steel Pile
4. Composite Pile: Concrete & Timber, Concrete & Steel
Based on the method of installation
1. Driven Pile
2. Cast-in-situ Pile
3.Driven and cast- in- situ Pile
9. a) Classification based on Function or Use
1. Bearing Piles or End Bearing Piles
2. Friction Piles or Skin Friction Piles
3. Sheet Piles
4. Tension Piles or Uplift Piles
5. Anchor Piles
6. Batter Piles
7. Fender Piles
8. Compaction Piles
10. I. Load bearing piles
II. Non-load bearing piles
I. Load bearing piles :-
It bear the load coming from the structure.
The Piles are generally driven vertically or in near vertical position.
When a horizontal forces to be resisted, the inclined piles may be
driven in an inclined position and such inclined piles are termed
the batter piles
Load bearing piles are divided into,
i. Bearing piles
ii. Friction Piles
11. Transmit most of their
loads to the load
bearing layer (dense
sand or rock). Most of
the pile capacity
inferred from the end
17. General facts
Usual length: 10m-20m
Usual load: 300kN-3000kN
Can be easily combined with a concrete superstructure
Difficult to achieve proper cutoff
Difficult to transport
19. 1. Pre Cast concrete pile
Precast concrete piles are those which are
manufactured in a factory or at a place away from
the construction site and then driven into the
ground at the place required. These piles require
heavy pile driving machinery.
Precast piles may be square, octagonal or circular
in cross section.
The size of piles may vary from 30 cm to 50 cm in
cross sectional dimension, and up to 20 m or more
The reinforcement may consist of longitudinal steel
bars of 20 mm to 40 mm in diameter, 4 to 8 nos.
with lateral ties of 6 to 10 mm diameter at 100 mm c/c
A concrete cover of at least 50 mm is provided. The
grade of concrete should be M20.
25. RAYMOND PILE
The Raymond standard pile is used primarily as
a friction pile. It is provided with uniform taper of
1 in 30 resulting in shorter piles.
The lengths of piles vary from 6 to 12 m. The
diameter of piles vary from 40 to 60 cm at the
top and 20 to 30 cm at the bottom.
Raymond piles have a high bearing capacity,
because of the corrugated surface of the pile
shaft and their conical pile shape. They are
suitable for high pile loads and difficult driving
33. Uncased cast in situ concrete
These piles are comparatively cheap, as no casing will
be left in the ground. But, great skill is required in this case to
achieve the desired results.
The common types of uncased cast in situ concrete piles are:
39. - Relatively inexpensive
- Usually limited to short lengths.
- Low capacity.
Easy handling. Non-corrosive material. If permanently submerged then
fairly resistant to decay.
May require treatment to prevent decay, insects, and borers from
damaging pile. Easily damaged during hard driving and inconvenient to
High axial working capacity. Wide variety of sizes. Easy
on-site modifications. Fairly easy to drive, minimal soil
displacement, good penetration through hard materials
High cost, difficulty in delivery, relatively higher
corrosion, noisy driving.
44. Non - Load bearing piles
This piles are used to function as the separating members
ground level and they are generally not designed to take
This piles are also known as the sheet piles.
The materials used for the construction of non load
bearing piles are,
i. Timber sheet piles
ii. Steel sheet piles
iii. Concrete sheet piles
45. SHEET PILES
Sheet piles are thin piles, made of plates of
concrete, timber or steel, driven into the ground for
either separating members or for stopping
seepage of water. They are not meant for carrying
any vertical load. Therefore, sheet piles are also
termed as non-load bearing piles.
47. SHEET PILES
1.Concrete sheet piles
Concrete sheet piles are
reinforced, precast units. The width of
each unit may vary from 50 cm to 60
cm and thickness varies from 2 cm to 6
The rainforcement is in the form
of vertical bars and hoops.
48. 2. Steel sheet pile:
Steel sheet piles are most commonly used.
They are trough shaped and when the piles are
interlocked with alternate once reversed.
They are generally made from steel sheets 20 to 30 cm
wide and 4 to 5 m long.
49. Different types of steel sheet piles are:
1. Arch web steel sheet pile.
2. Built up steel sheet pile.
3. Z-type steel sheet pile.
4. Corrugated steel sheet pile.
5. Deep arch web steel sheet pile.
6. Universal joint steel sheet pile.
53. These piles are successfully developed by
C.B.R.I., Roorkee (U.P.) for serving as foundations
for black cotton soils, filled up ground and other
types of soils having poor bearing capacity.
An under reamed is a cast-in-situ concrete
pile having one or more bulbs or under-reams in
its lower portion. The bulbs or under-reams are
formed by under reaming tool. The diameter of
under reamed pile varies from 20cm to 50cm and
that of bulb varies from 2 to 3 times the diameter of
Under reamed piles
59. Sometimes the piles are arranged in close-
spaced groups. When the piles are driven to
the required depth, their tops are cutoff a
same level and then the pile cap is provided.
In case of single pile small pressure is developed
in the surrounding soil. And in case of group piles,
the pressure developed surrounding the individual
piles will overlap laterally and the pressure in the
overlapping zone will be sufficient to cause movement
of the soil and the pile will settle down.
60. The spacing of pile is the center to center distance between two successive piles.
The factors to be considered while deciding the pile spacing are as follows:
1. The nature of soil through which the pile is driven.
2. The obstruction during pile driving
3. The type of pile
4. The depth of penetration
5. The area of cross section of the pile
6. The centre to centre distance of piles in a group
7. The manner in which the pile supports the load
8. The material of pile
62. In case of Wooden Piles, Steel Piles, Pre-cast Concrete Piles, to
protect the top and bottom of the Pile while driving into the ground
and to facilitate easy Pile driving certain accessories are required as
1. Pile Cap
2. Pile Shoe
63. Pile caps carrying very heavy point loads tend to produce high
tensile stresses at the pile cap.
Reinforcement is thus designed to provide:
◦ Resistance to tensile bending forces in the bottom of the cap
◦ Resistance to vertical shear
64. While driving wooden or steel pile by hammer the bottom
end of the pile gets damaged causing difficulty in driving.
Therefore, a pile shoe is fitted at the bottom end of the pile
to protect the pile and to facilitate easy pile driving.
Pile shoe are made of cast iron, steel iron.
65. Various Types of Pile Shoe :
1. Square Pile Shoe
2. Wedge shape Shoe
3. Round Pile Shoe
4. Steel Trap shoe
5. Socket Type pile shoe
6.Closed end shoe for pipe pile.
67. Piles are commonly driven by means of a hammer supported by a
crane or a special device known as a Pile Driver.
Hammers adopted for driving the pile are of the
1. Drop hammer
2. Single acting hammer
3. Double acting hammer
4. Diesel hammer
5. Vibratory hammer.
68. 1.Drop hammer
The drop hammer in the pile driving equipment consists of a
heavy hammer in between the leads. The hammer is lifted up
to a certain height and drop on the pile.
79. Absence of statistical data regarding the nature of soil strata
through which the piles are to be driven.
Actual load coming on the pile being more than the design load.
Bad workman ship in case of the cast-in-situ cement concrete
Breakage due to over driving especially in case of the timber
Buckling of piles due to removal of side support, inadequate
lateral support, etc.
80. Lateral forces (wind, waves, currents etc.) not being
taken into the design of the pile.
Improper choice of the type of pile.
Improper choice of the method of driving the pile.
Improper classification of pile.
Insufficient reinforcement or misplacement of
reinforcement in case of the R.C.C. piles.
Wrongful use of pile formula for determining its load
81. Preliminary pile design
is first carried out on
the basis of site
laboratory soil testing,
and office study.
Pile load tests are
then carried out to
refine and finalize the
design. For these
conditions, the test
piles are generally
tested to failure. 81