bct%20final.pptx

SHALLOW FOUNDATION
INTRODUCTION
Every building consists of two basic
components:
 The Super Structure and
 Sub Structure or Foundations
Super structure is that part of building
which is above ground & serves purpose
of its internal use.
Foundation is lower portion of building,
usually located below ground , transmits
load of super structure to sub soil. It is that
part of structure which is in direct contact of
ground to which load is
transmitted. Soil which is located
immediately below base of foundation is
called foundation soil, while lower most
portion of foundation which is in direct
contact with sub soil is called footing.

 Cracked walls
 Distorted door & window openings
 Cracked lintels
SHALLOW FOUNDATION
INTRODUCTION
Function of any foundation is to safely
sustain & transmit combined dead, live
load & wind loads to ground on which it
rests, in a manner as:
 Not to cause any settlement or other
movement which would weaken
stability
 Cause damage to any part of
building
 Sub soil does not fail under load
If this settlement is slight & uniform
throughout, no damage will be caused to
building. But if it is excessive or unequal,
serious damage may result in the form of

SHALLOW FOUNDATION
TYPES
 Walls thrown out of plumb etc. and
 Complete collapse of building
Foundations divided into two categories:
 Shallow foundations and
 Deep foundations.
Words shallow & deep refer to depth of
soil in which foundation is made.
 Shallow foundations can be made in
depths of as little as 1m, while deep
foundations can be made at depths of
20 - 65m.
 Shallow foundations are used for
small, light buildings, while deep

SHALLOW FOUNDATION
TYPES
According to Terzaghi, a foundation is shallow if its depth is equal to or less than its
width. It is also known as Open Foundation, since such foundation is constructed
by open excavation.
Foundation which have depth even greater than its width, but are constructed by
way of open excavation also come under “ Shallow Foundation”.
Term footing is commonly used in conjunction with shallow foundations. It is a
foundation unit constructed in brickwork, masonry or concrete under base of a wall
or column for purpose of distributing load over a larger area.

SHALLOW OR
OPEN
1. SPREAD
FOOTING
2. INVERTED
ARCH
4. CANTILEVER
OR STRAP
5. MAT /
RAFT
SHALLOW FOUNDATION
TYPES
a. STRIP b. PAD / ISOLATED
i. SIMPLE
ii. STEPPED
iii.
FOOTING
FOR RC
COLUMN
iv.
GRILLAGE
i. SIMPLE
ii.
STEPPED
3. COMBINED
FOOTING
a. RECTANGULAR
b. TRAPAZOIDAL
c. CONTINUOUS
a. SOLID SLAB
b. BEAM & SLAB
c. CELLULAR
STEEL
TIMBER

SHALLOW FOUNDATION
TYPICAL PAD FOUNDATION TYPES
TYPES

1. Spread Footing
b. Pad or Isolated Footing:
iv. Grillage Foundations:
Special type of isolated footing
provided for heavily loaded steel
stanchions, specially in those
locations where bearing capacity of
soil is poor.
Depth of foundation is limited from 1
to 1.5m. Load of stanchion is
distributed to a large area by means
of tiers of joists. Each tiers being
placed at right angles to next tier.
Grillage Foundations are of two types:
 Steel Grillage Foundation and
 Timber Grillage Foundation
STEEL
STANCHION
BRICK WALL
SHALLOW FOUNDATION :
TYPES

1. Spread Footing
Steel Grillage Foundations:
 Constructed of steel beams,
known as RSJ, provided in two or
more tiers.
 Joists of each tier are held in
position by 20mm dia spacer bars
with 25mm dia pipe separators.
 Grillage beams are embedded in
concrete. Minimum clearance of
80mm is kept between grillage
beams so that concrete can be
easily poured & properly
compacted. GRILLAGE FOUNDATION FOR
STEEL STANCHION
SHALLOW FOUNDATION
TYPES

SHALLOW FOUNDATION
TYPES
1. Spread Footing
 Distance between flanges should
not exceed 300mm or 1.5 times
flange width so that filled concrete
acts monolithically with beams.
 Concrete filling does not carry any
load, it simply keeps beam in
place & prevents corrosion.

SHALLOW FOUNDATION
TYPES
1. Spread Footing
 Minimum concrete cover of
100mm is kept on outer sides of
the external beams, as well as
upper flanges of top tier.
 Depth of concrete below the lower
tier should be at least 150mm.
Method of Construction:
 Foundation excavated to required
depth.
COMBINED TRAPEZOIDAL STEEL

 Generally, it is shallow. Sufficient
to accommodate two tiers of
Grillage beams & gusset plate etc.
connecting the stanchion to base.
 However, depth should not be less
than 900mm in any case.
 After levelling foundation base,
rich concrete is poured &
compacted so that formed
thickness is not less than150mm. COMBINED TRAPEZOIDAL STEEL
SHALLOW FOUNDATION
TYPES
1. Spread Footing

 Compaction should be done
properly so that the layer of
concrete is becomes an
impervious bed.
 This will protect steel joists against
the ground water.
 After levelling concrete, first tier of
Grillage beams of designed sizes
are laid over it, at proper distance
with the help of separators.
 surface of all beams should lie in
one horizontal plane.
STEEL GRILLAGE FOUNDATIONS FOR
WALLS
SHALLOW FOUNDATION
TYPES
1. Spread Footing

SHALLOW FOUNDATION
TYPES
 Rich cement grout is poured all
around lower flanges of beams so
that they are secured to concrete
bed.
 Cement concrete is then poured
between & around beam of first tier.
 Second tier of beams is then placed
at right angles to the first tier & over
top flanges of beam of first tier.
 They are properly spaced with help of
separators. Concrete is then poured
between & around steel beams.
 Steel stanchion then connected to
upper tier with help of base plate,
side angles & gusset plate.

Steel Grillage Foundation may also be
provided for a masonry wall or soils of
low bearing capacity. Grillage
Foundation for such a case consists of
only one tier, though in some
circumstances when the wall is wider & it
carries heavy loads, two tiers may also
be provided.
STEEL GRILLAGE
SHALLOW FOUNDATION
TYPES
 These connecting members are also
embedded into concrete so that the
joint becomes rigid.

SHALLOW FOUNDATION
TYPES
1. Spread Footing
iv. Grillage Foundations
Timber Grillage Foundations:
Provided for heavily loaded timber
column or masonry wall. Foundation
uses timber planks & timber beams in
place of steel joists.
It is useful in water logged areas where
bearing power of soil is very low & where
steel beams may get corroded due to
subsoil water.
Loading on soil is limited to 50 to
60kN/m2.

SHALLOW FOUNDATION
TYPES
1. Spread Footing
iv. Grillage Foundations
No concrete is embedded between
timber joints. Bottom concrete replaced
by timber platform of timber planks

placed at right angle to this timber
SHALLOW FOUNDATION
TYPES
Method of Construction
 After excavating foundation of
required depth & levelling it, bottom
layer of planks 50 to 75mm thick &
200 to 300mm wide is laid.
 Planks are arranged side by side,
without any gap between them. Over
this platform, a tier of wooden beams,
about 150x100mm in size spaced
300 to 500mm apart is laid at right
angles to the direction of planks.
 Over top of this layer, timber beam of
same section is that of wood post is
GRILLAGE FOUNDATION FOR WOODEN POST

Upper layer of planks placed (side by
side) may be 75 to 100mm thick,
extending over full width of wall base &
running longitudinally along the wall.
Lower layer of planks may be 50 to
75mm thick placed longitudinally along
wall. However, lower layer of timber
planks & also middle tier of timber
beams, should extend to at least 450 to
600mm on either side of wall footing
TIMBER GRILLAGE FOUNDATION FOR
MASONRY WALL
base.
SHALLOW FOUNDATION
TYPES
Figure shows Timber Grillage
Foundation for a wall. Foundation
consists of two layers of wood planks
separated by rectangular sections of
timber placed at right angle to direction
of wall.

INVERTED ARCH FOUNDATION
SHALLOW FOUNDATION
TYPES
2. Inverted Arch Footing:
Used on soft soils to reduce the depth of
the foundation. Loads above an opening
are transmitted from supporting walls
through inverted arches to the soil.
Following should be noted:
i.It should be set in cement mortar.
ii.End pier should be designed to
resist outward pressure caused by
arch action
iii.Rise is about one fifth to one tenth
of the span & they are usually build in
half brick rings.
iv.Position of inverted arches may be
either along the raw of piers or in
both directions, depending on the
nature of soil & type of load.

TYPES
2. Inverted Arch Footing:
v.Depth of foundation is considerably
reduced when this method is adopted &
hence , economical in case of foundation
of soft soil
vi.This method of spreading the weight
over a large area is not common for the
construction of foundation of buildings.
But it is suitable for the foundation of
structures such as
Bridges
Reservoirs,
Supports for drainage lines,
Tanks etc.

Generally, they are constructed of RC. In
design of footing, footing is assumed to
be rigid & resting on homogeneous soil.
Location of centre of gravity of column
load & centroid of footing should
coincide.
COMBINED FOOTING
SHALLOW FOUNDATION
TYPES
3. Combined Footing:
It supports two, three or more columns in
a row.
 It can be rectangular in shape if both
the columns carry equal load or
 Can be trapezoidal, if there are
 Space limitation &
 They carry unequal load

TYPES
3. Combined Footing:
c. Continuous Footing:
A single RC slab is provided as
foundation of two or more columns in a
row.
 It is suitable at locations liable to
earthquake activities.
 This also prevents differential
settlement in the structure.
In order to have better stability a deep
beam is constructed in between the
columns.

SHALLOW FOUNDATION
TYPES
4. Strap or Cantilever Footing:
Consists of two or more individual
footings connected by beam called strap.
It is also sometimes called as Cantilever
Footing or Pump Handle Foundation.
It can be used where it is necessary to
avoid imposing any pressure on an
adjacent foundation or underground
services.
It may be used where distances between
columns is so great that a combined
trapezoidal footing becomes quite
narrow with high bending moments.

CANTILEVER FOUNDATION TYPES
SHALLOW FOUNDATION
TYPES

TYPES
Strap beam does not remain in contact
with soil, so a strap does not transfer any
pressure to soil. However, because strap
is infinitely stiff, hence it seems to
transfer column loads on to soil with
equal & uniform soil pressure under both
footing.
Grillage Strap Footing:
Strap footings are commonly constructed
in RCC. However, for steel stanchions,
grillage strap footings may be used,
specially for the circumstances where
the depth of footing has to be shallow
and where soil has low bearing capacity
GRILLAGE STRAP FOOTING

COMMON ARRANGEMENT OF
STRAP FOOTINGS
STRAP FOOTING
SHALLOW FOUNDATION
TYPES
Strap beam does not remain in contact
with soil, so a strap does not transfer any
pressure to soil. However, because strap
is infinitely stiff, hence it seems to
transfer column loads on to soil with
equal & uniform soil pressure under both
footing.

SHALLOW FOUNDATION
TYPES
5. Mat or Raft Foundation:
It is a foundation unit continuous in two
directions covering an area equal to or
greater than base area of building.
It is used to spread the load of the super
structure over a larger base to reduce
the load per unit area being imposed on
the ground.
This is particularly useful :
 Where low bearing capacity soils are
encountered and
 Where individual column loads are
heavy.
COMMON TYPES OF RAFT FOUNDATION

TYPICAL RAFT FOUNDATION TYPES
TYPES
Three types of RC Raft foundations are:
1.Solid Slab Raft Foundation
2.Beam & Slab Raft Foundation
3.Cellular Raft Foundation
a. Solid Slab Raft Foundation:
It is a solid RC slab generally of uniform
thickness, cast on subsoil of poor or
variable bearing capacity, so that the
loads from walls or columns of light
loaded structures are spread over the
whole area of the building.
RCC RAFT WITH SLAB ONLY

SHALLOW FOUNDATION
COMMON TYPES OF RAFT FOUNDATION
TYPES
b. Beam & Slab Raft Foundation:
As a foundation to support heavier loads
of walls of columns a solid slab raft
would require considerable thickness.
To make most economical use of RC in
a raft foundation supporting heavier
loads it is a practice to form a beam &
slab raft.
This consists of upstand or down stand
beams that take loads of columns &
spread them to monolithically cast slab
which bears on natural subsoil.
BEAM & SLAB RAFT FOUNDATION

SHALLOW FOUNDATION
BEAM & SLAB RAFT FOUNDATION
TYPES
b. Beam & Slab Raft Foundation:
On compact soil which can be excavated
without the necessity of timbering to
trenches,
it is economical to use down stand
beams & where the subsoil is granular,
upstand beams may be necessary.

CELLULAR RAFT FOUNDATION
SHALLOW FOUNDATION
TYPES
5. Mat or Raft Foundation
c. Cellular Raft Foundation:
Where differential settlement are likely to be significant and foundations have to
support considerable loads the great rigidity of monolithically cast RC cellular RC
raft is an advantage. This consists of top & bottom slabs separated by & reinforced
with vertical cross ribs in both directions.

TYPES
5. Mat or Raft Foundation
c. Cellular Raft Foundation:
This has great rigidity & spreads
foundation loads over the whole area of
the substructure to reduce consolidation
settlement & avoid differential
settlement.
A cellular raft may be the full depth of a
basement storey and the cells of the raft
may be used for mechanical plant &
storage.

SHALLOW FOUNDATION
TYPES
SHALLOW FOUNDATIONS

TYPES
SHALLOW FOUNDATIONS
.

DEEP FOUNDATION:
INTRODUCTION
Depth of foundation is very large in
comparison to its width. They are not
constructed by ordinary methods of open
pit excavations. They are of following
types:
1.Pile foundation
2.Pier foundation
3.Caisson or Well foundation
Of these, pile foundation is more
commonly used in building construction.
These foundation carry loads from a
structure through
Weak compressible soil or
Fills on to the stronger and less
compressible soils or
rocks at depth
STAGES IN CONSTRUCTION OF LARGE
DIA BORED PILE WITH UNDER-REAM

DEEP FOUNDATION:
INTRODUCTION
These foundations are in general used
as
 Basement
 Buoyancy rafts
 Caissons
 Cylinders
 Shaft and
 Piles
It is preferred in following situations:
1. Load of super structure is heavy & its
distribution is uneven.
2. Top soil has poor bearing capacity
3. Subsoil water is high so that pumping
of water from open trenches for the
shallow foundations is difficult &
uneconomical .

DEEP FOUNDATION:
INTRODUCTION
4. There is large fluctuation in subsoil
water level.
5. If deep strip foundation is attempted,
timbering of sides is difficult to
maintain or retain the soil of sides of
the trench.
6. If the structure is situated on sea
shore or river bed, where there is
danger of scouring action of water.
7. Canal or deep drainage line exists
near the foundation.
8. Top soil is of expensive nature.
COMPONENTS OF WELL
FOUNDATION

FOUNDATION:
PILE FOUNDATION
Use of Pile as foundation can be traced
since olden times. Today, pile foundation
is much more common than any other
building type of deep foundation.
Modern pile driving started with the first
steam pile drivers, invented by Nasmyth
in 1845.
It is a construction supported on piles. A
pile is an element of construction
composed of:
 Timber
 Concrete
 Steel or
 Combination of above

FOUNDATION:
PILE FOUNDATION
Pile foundation may be defined as a
column support type of foundation which
may be cast in situ or precast.
The piles may be placed separately or
they may be placed in form of cluster
throughout the length of structure.
This type of construction is adopted
when loose soil extends to a great depth.
The load of structure is
 Transmitted by piles to the hard
stratum below or
 It is resisted by the friction developed
on sides of piles

DEEP FOUNDATION:
PILE FOUNDATION
CLASSIFICATION
Broadly classified based on following:
I.Based on the function and
II.Based on material & composition
Classification Based on Function:
1.Bearing pile
2.Friction pile
3.Screw pile
4.Compaction pile
5.Uplift pile
6.Batter pile
7.Sheet pile
CLASSIFICATION BASED ON FUNCTION

DEEP FOUNDATION
PILE FOUNDATION
1.End Bearing Pile
It penetrates through the soft soil & their
bottoms or tips rest on hard stratum. The
soft ground through which the piles pass
also gives some lateral support and this
increases the load carrying capacity of
the bearing piles. These piles act as
columns.
2.Friction Piles
When loose soil extends to a great
depth, piles are driven up to such a
depth that frictional resistance developed
at the sides of the piles equals to the
load coming on piles.

DEEP FOUNDATION
PILE FOUNDATION
2.Friction Piles
The total frictional resistance of piles is
obtained by multiplying frictional
resistance of soil with the area of pile in
contact with the soil. The total frictional
resistance can be increased by:
Increasing diameter of piles
Driving piles to a greater depth
Making surface of pile rough
Placing the piles closely and
Grouping the piles

DEEP FOUNDATION:
PILE FOUNDATION
3.Screw Piles
It consists of a hollow cast iron or steel
cylinder with one or more blades at the
bottom.
The blades are generally made of cast
iron. The bottom end of the screw pile
with blunt point is useful when ground to
be penetrated consists of sand and clay.
Screw piles when provided with
Gimlet point for gravely ground
Hollow conical point for sand mixed
gravel ground and
Serrated point for soft rock

DEEP FOUNDATION:
PILE FOUNDATION
3.Screw Piles
The number of helices, their diameters
and position on the pile shaft as well as
steel plate thickness are all determined
by a combination of:
 The combined structure design load
requirement
 The geotechnical parameters
 Environmental corrosion parameters
 The minimum design life of the
structure being supported or
restrained.

DEEP FOUNDATION:
PILE FOUNDATION
3.Screw Piles
Used extensively, and their usage has
extended from
 Lighthouses to rail,
 Telecommunications,
 Roads
 Numerous other industries where fast
installation is required, or
 Building work takes place close to
existing structures.
Most industries use screw pile
foundations due to the cost efficiencies
and - increasingly - the reduced
environmental impact.

DEEP FOUNDATION:
PILE FOUNDATION
3.Screw Piles
Screwing' the foundations in ground
means that there is less soil
displacement so excess soil does not
need to be transported from site, saving
on transportation costs and reducing the
carbon footprint of the project.
Main benefits of screw pile foundations:
 Shorter project times
 Ease of installation & access,
 Reduction of the carbon footprint,
 Ease of removal when the
foundations are no longer required,
 Reduced risk to the workforce, and
 Reduced costs.

DEEP FOUNDATION:
PILE FOUNDATION
4.Compaction Piles
Used for foundations of structure of
various types such as
 Residential and industrial buildings,
 Overhead tanks,
 Towers,
 Substations,
 Gantry foundations,
 Underground tanks,
 Overbridges etc.
They are used to compact loose granular
soils in order to increase their bearing
capacity. These piles themselves do not
carry any load.

DEEP FOUNDATION:
PILE FOUNDATION
4.Compaction Piles
Combines the advantage of both bored
and driven piles by compacting freshly
laid concrete and soil around obtaining
increased load carrying capacity over
normal piles.
Suitable for loose to medium silty/sandy
soils specially with high water table.
No adverse effects on the environment.

DEEP FOUNDATION:
PILE FOUNDATION
4.Compaction Piles
They are used to compact loose granular
soils in order to increase their bearing
capacity. These piles themselves do not
carry any load.
5.Uplift Piles
These piles anchor down the structure
subjected to uplift pressure due to
overturning movement.
6.Batter Piles
They are used to resist large horizontal
or inclined forces.

DEEP FOUNDATION
PILE FOUNDATION
7.Sheet Piles
They are retaining walls constructed to
retain earth, water or any other filling
materials.
These walls are thinner in section
compared to masonry walls. Sheet pile
walls are generally used for following:
 Water front structures, i.e. in building
wharfs, quays and piers.
 Building diversion dams, such as
cofferdams
 River bank protection

DEEP FOUNDATION
PILE FOUNDATION

DEEP FOUNDATION:
PILE FOUNDATION

FOUNDATION:
PILE FOUNDATION
Selection Between Different Piles:
The factors which govern the choice
between different types of pile are:
1.Nature of soil at site
2.Type, size and weight of structure to
be supported
3.Depth, extent and nature of strata for
supporting piles
4.Availability of material for piles
5.Number of piles required
6.Cost comparatives
7.Type of structure adjacent to project
site
8.Pressure of water if any above surface
into which piles are to be driven
COMPOSITE PILE

DEEP FOUNDATION:
PILE FOUNDATION
Classification Based on Material &
Composition:
Following are the most common types:
1.Cast-iron Piles
2.Cement Concrete Piles
3.Timber Piles
4.Steel Piles
5.Sand Piles and
6.Wrought-iron Piles
7.Composite Piles

PILE FOUNDATION:
MATERIAL BASED CLASSIFICATION
1.Cast-iron Piles
 They are generally hollow.
 Inside diameter is about 300mm &
thickness about 25mm.
 Length is about 3 to 4m & can be
extended to the desired length with
help of suitable device.
 Cast-iron being brittle material, not
possible to drive into ground with
hammer. Hence, special screws are
provided at the bottom & they are
driven like a screw into the ground.
These are known as Cast-iron screw
piles.
Cast-iron Pile Shoe

PILE FOUNDATION:
1.Cast-iron Piles
Advantages Disadvantages
Useful for areas where the timber piles
will be attacked & damaged by insects
It cannot be subjected to shocks or
vibrations
Suitable for heavy vertical pressure Not suitable for works under sea water
If shocks or vibrations would endanger
the adjacent properties, Cast-iron piles
are preferred

PILE FOUNDATION:
2. Cement Concrete Piles
Possess excellent compressive strength.
These can be reinforced or prestressed
type. They can be divided into following:
a. Precast Concrete Piles and
b. Cast in Situ Concrete Piles
i. Driven Piles: Cased or Uncased
ii. Bored Piles
 Pressure Piles
 Under-reamed Piles &
 Bored Compaction Piles
INSTALLATION OF FRANKIE PILE

PILE FOUNDATION:
2. Cement Concrete Piles
a. Precast Concrete Piles
 Manufactured in factory.
 May be tapered or parallel sided.
 May be Square, Octagonal or Round
 Used for a maximum design load of
80 T Reinforced to withstand
handling stress
 Require space for casting & storage
 Require more time to set & cure
before installation
 Need heavy equipment for handling
& driving
 Incur large cost in cutting off extra
length or adding more length. PRECAST CONCRETE PILES

DEEP FOUNDATION:
PILE FOUNDATION
Composition:
a.Precast Concrete Piles
Used for maximum design load of 80T
Reinforced to withstand handling
stress
Require space for casting and storage
Require more time to set & cure before
installation
Need heavy equipment for handling &
driving
Incur large cost in cutting off extra
length or adding more length.
PRECAST RCC SHEET PILES

DEEP FOUNDATION
PILE FOUNDATION
Composition:
These piles can be driven under water. It
is possible to have a proper control over
the composition & design of these piles
as they are manufactured in factory
Any defect of casting such as hollows
etc. can be found out and repaired
before driving the pile.
These piles possess high resistance to
biological & chemical actions of ground.
PRECAST PILES

DEEP FOUNDATION
PILE FOUNDATION
Classification Based on Material & Composition:
Concrete piles should correspondence to M200. usually lifting points are specified
at 0.207 of its length from either end, so that magnitude of maximum bending
moment due to handling is kept at lowest possible value.

DEEP FOUNDATION
PILE FOUNDATION
Composition:
a.Precast Concrete Piles – Casting
Formwork is prepared & coated with
soap solution or oil to prevent adhesion.
Reinforcement cage prepared & placed
into formwork.
Minimum cover of 50mm shall be
ensured all around.
Concrete of required proportion laid in
formwork. Concrete should be laid till the
pile is completely filled up.
PRECAST PILES

DEEP FOUNDATION
PILE FOUNDATION
Composition:
a.Precast Concrete Piles – Casting
Vibrators are used for the consolidation
of concrete. It should be observed that
all the edges & corners are sharp,
straight & unbroken when formwork is
removed
Forms are removed after 3 days &
piles are kept in the same position for
about 7 days minimum.
The piles are then shifted to curing
tank & after a period of about 3 to 4
weeks, they are ready for use.

DEEP FOUNDATION
PILE FOUNDATION
a.Precast Concrete Piles – Advantages & Disadvantages
Position of reinforcement undisturbed Heavy in weight, difficulty in transport
Can be driven underwater. Extra reinforcement provided to resist
stresses develop during handling &
driving operation makes it costly.
For ground water containing 5000ppm ,
cast in situ concrete may not set & under
such condition precast piling is only
option
Length decided from trial bores. Extra
length, if required, made on site. Weak
connection. In case of extra long, it is to
be cut on site. Wastage of material.
Quality control over design, composition
& workmanship
Chances of breakage in transit or driving

DEEP FOUNDATION
PILE FOUNDATION
a.Precast Concrete Piles – Advantages & Disadvantages
Defects can be found & rectified in
advance
If not available at short notice, project is
delayed
Any numbers can be manufactured at
convenient place & prove economical
Requires heavy pile driving equipment
When driven in ground, ready to take
load. Saving in time.
Size & length of pile dictated by available
transport facilities
Possess high resistance to biological &
chemical action in ground
Excessive driving can cause fine cracks
in concrete
Driving of these piles is smooth, it does
not develop any adverse effect on
adjacent installed piles.

DEEP FOUNDATION
PILE FOUNDATION
Composition:
a.Precast Concrete Piles – Repairing
It can be repaired by following method:
 By lowering a permanent jacket
either of steel or precast concrete
around the pile & filling with tremie
grout.
 By using underwater setting cement
 By using under water setting epoxy
 By using RCC jacket cast in a
temporary form
 By using shotcrete which is applied
over wire mesh

DEEP FOUNDATION
PILE FOUNDATION
CONCRETING USING TREMIE PIPE

FOUNDATION:
PILE FOUNDATION
Composition:
b.Cast in Situ Concrete Piles
A bore is dug into the ground by
inserting a casting.
This bore is then filled with cement
concrete after placing reinforcement, if
any.
They may be either cased or uncased
cast in situ concrete piles depending
upon whether the casing is kept in
position or is withdrawn afterwards.

DEEP FOUNDATION
PILE FOUNDATION
Composition:
b.Cast in Situ Concrete Piles
A variety of patented process have been
developed under both categories. The
most common amongst them are:
Raymond Piles
Mac-Arthur Piles
Monotype Piles
SF Base Driven Piles
Button Bottom Piles
Samplex Piles
Franki Piles
RAYMOND PILES

FOUNDATION:
PILE FOUNDATION
Composition:
b.Cast in Situ Concrete P
Easy to handle & drive in the ground Difficult to maintain reinforcement in
correct position during construction
Do not require any extra reinforcement
to resist stresses developed during
handling or driving operation
Cannot be constructed under water
No wastage of material as the piles of
required length is constructed.
Not possible to have proper control over
the composition & design of these piles.
Extra cost of transporting pile is also
eliminated.

DEEP FOUNDATION:
PILE FOUNDATION
Composition:
3.Timber Piles
Prepared from trunk of trees. May be
circular or square.300 to 500mm in
diameter, with length not exceeding 20
times its top width.
At bottom, a cast iron shoe is provided
& at top steel plate is fixed. If group of
pile is driven, top of each member is
brought at same level & then concrete
cap is provided to have a common
platform

FOUNDATION:
PILE FOUNDATION
Composition:
2.Timber Piles
They have a small bearing capacity &
are not permanent unless treated.
Difficult or impossible to drive into hard
strata or boulders.
Economical where timber is available
easily
TIMBER SHEET PILES

DEEP FOUNDATION:
PILE FOUNDATION
Composition:
3.Steel Piles
Used in following different forms:
i.H – Piles
ii.Box Piles and
iii.Tube Piles
i.H – Piles
Usually of wide flange section.
Suitable for trestle type piers in which
piles extend above ground level and also
acts as columns.
STEEL PILES
STEEL SHEET PILES

DEEP FOUNDATION
PILE FOUNDATION
Composition:
3.Steel Piles
i.H – Piles
Since they have small cross sectional
area, therefore, can be easily driven in
soils in which it will be difficult to drive
ordinary displacement piles.
Used as long piles with high bearing
capacity
STEEL SHEET PILE

FOUNDATION:
PILE FOUNDATION
Composition:
3.Steel Piles
ii.Box Piles
Rectangular or octagonal in form, filled
with concrete.
Used when it is not possible to drive H-
pile into hard strata
iii.Tube Piles
Tube or pipes are driven into the ground.
Concrete is filled inside the tube piles.
Because of their circular cross section,
these piles are easy to handle and drive
in.

FOUNDATION:
PILE FOUNDATION
Composition:
3.Steel Piles
iii.Tube Piles
Advantages are:
Can easily withstand stress due to
driving.
Can be easily lengthened by welding
and can also be cut off easily
Can resist lateral forces in a better way
Bearing capacity comparatively high
Can take up impact stresses

FOUNDATION:
PILE FOUNDATION
Composition:
3.Steel Piles
iii.Tube Piles
The only disadvantage is their corrosion.
To prevent corrosion:
Should be coated with paint or
May be encased with cement concrete

DEEP FOUNDATION:
PILE FOUNDATION
Composition:
4.Sand Piles
Formed by making holes in ground &
then filling them with sand.
Top of the sand piles is filled with
concrete to prevent the sand ejecting
upwards due to lateral pressure.
Sand piles are spaced at 2 to 3m.
Its lengths is kept about 12times its
diameter.
They are easy t construct and can be
used for any position of water table.
.
STAGES IN RAYMOND STANDARD PILE
CONSTRUCTION

FOUNDATION:
PILE FOUNDATION
Composition:
4.Sand Piles
Not suitable
For loose or wet soils
Where there is danger of scour and
In region subjected to frequent
earthquakes.

FOUNDATION:
PILE FOUNDATION
Composition:
5.Composite Piles
Formed
When it is combination either of a
bored pile & driven pile or
Piles made up of two different
materials.
Suitable where the upper part of pile is to
project above the water table. They are
economical & easy to construct

FOUNDATION:
PILE FOUNDATION
Design of Piles:
Following loads & forces are taken into
consideration:
 Direct vertical load to be
transmitted by pile
 Impact stresses developed during
process of pile driving
 Bending stresses developed due to
curvature & eccentricity of loads
coming on to piles
 Stresses developed during
handling operation
 Lateral forces due to wind, waves,
currents of water etc.
 Forces due to impact of ship, in
case of marine structure

FOUNDATION:
PILE FOUNDATION
Design of Piles:
Following loads & forces are taken into
consideration:
 Impact forces due to ice sheets
 Forces due to uplift pressure if any
and
 Earthquake forces
.
.

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