1. TYPES OF FOUNDATION

2. TYPES OF FOUNDATION a) Shallow Foundation System i) Spread Foundation
ii) Mat / Raft Foundation
b) Deep Foundation System
i) Pile iii) Diaphragham wall
ii) Pile walls iv) Caissons

3. SHALLOW FOUNDATION Advantages Cost (affordable)
Construction Procedure (simple)]
Material (mostly concrete)
Labour (doesn’t need expertise)

4. SPREAD FOOTING FOUNDATION
Also known as a footer or footing
It’s an enlargement at the bottom of a column/
bearing wall that spreads the applied
structural loads over a sufficiently large soil
area.
Each column & each bearing wall has its own
spread footing, so each structure may include
dozens of individual footings.

5. SPREAD FOUNDATION

6. The foundation consists of concrete slabs
located under each structural column and a
continuous slab under load-bearing walls.
For the spread foundation system the
structural load is literally spread out over a
broad area under the building
Most common type of foundation used due
to their low cost & ease of construction.
Most often used in small to medium size structure with moderate to good soil condition.

7. Spread footings may be built in different
shapes & sizes to accommodate individual
needs such as the following:
a) Square Spread Footings / Square Footings
b) Rectangular Spread Footings
c) Circular Spread Footings
d) Continuous Spread Footings
e) Combined Footings
f) Ring Spread Footings

8. a) Square Spread Footings / Pad Foundation
- support a single centrally located column
- use concrete mix 1:2:4 and reinforcement
- the reinforcement in both axes are to
resist/carry tension loads.

9. PAD FOUNDATION

10. b) Rectangular Spread Footings
- Useful when obstructions prevent
construction of a square footing with a
sufficiently large base area and when
large moment loads are present

11. c) Circular Spread Footings
- are round in plan view
- most frequently used as foundation for
light standards, flagpoles and power
transmission lines.

12. d)Continuous Spread Footings / Strip Foundation
- Used to support bearing walls

13. e) Combined Footings
- support more than one column
- useful when columns are located too close
together for each to have its own footing

14. f) Ring Spread Footings
- continuous footings that have been wrapped into a
circle
- commonly used to support the walls above-ground
circular storage tanks.
- The contents of these tanks are spread evenly
across the total base area and this weight is probably
greater that the tank itself
- Therefore the geotechnical analyses of tanks usually
treat them as circular foundations with diameters
equal to the diameter of the tank.

15. Ring Spread Footings

16. RAFT FOUNDATION A foundation system in which essentially the
entire building is placed on a large continuous
footing.
It is a flat concrete slab, heavily reinforced
with steel, which carries the downward loads
of the individual columns or walls.
Raft foundations are used to spread the load
from a structure over a large area, normally
the entire area of the structure.

17. MAT/RAFT FOUNDATION

18. It is normally consists of a concrete slab
which extends over the entire loaded area.
It may be stiffened by ribs or beams
incorporated into the foundation.
Raft foundations have the advantage of reducing differential settlements as the concrete slab resists differential movements between loading positions.
They are often needed on soft or loose soils with low bearing capacity as they can spread the loads over a larger area.

19. Mat Foundation often considered to be
used when dealing with the following
conditions:
The structural loads are so high or the soil condition so poor that spread footings would be exceptionally large. As a general rule of thumb, if spread footings would cover more than 50% of the building footprint area, a mat or some type of deep foundation will usually be more economical.

20. b) The soil is very erratic & prone to excessive differential settlements. The structure continuity and flexural strength of a mat will bridge over these irregularities.
The same is true of mats on highly expansive soils prone to differential heaves.
c) The structural loads are erratic and thus increase the likelihood of excessive differential settlements. Again, the structural continuity and flexural strength of the mat will absorb these irregularities.

21. d) The lateral loads are not uniformly distributed through the structure and thus may cause differential horizontal movements in spread footings and pile caps.
The continuity of a mat will resist such movement.
e)The uplift loads are larger than spread footings can accommodate. The greater weight and continuity of a mat may provide sufficient resistance.

22. f) The bottom of the structure is located below the groundwater table, so waterproofing is an important concern. Because mats are monolithic, they are much easier to waterproof. The weight of the mat also helps resist hydrostatic uplift forces from the groundwater.

23. DEEP FOUNDATION Extend several dozen feet below the building a) Piles
b) Piers
c) Caissons
d) Compensated Foundation

24. PILES????? A slender, structural member
consisting steel or concrete or timber.
It is installed in the ground to transfer
the structural loads to soils at some
significant depth below the base of the
structure.

25. PILES

26. PILES FOUNDATION IS USED WHEN:
The soil near the surface doesn’t have
sufficient bearing capacity (weak) to support
the structural loads.
The estimated settlement of the soil exceeds
tolerable limits
Differential settlement due to soil variability
or non-uniform structural loads is excessive
Excavations to construct a shallow foundation
on a firm soil are difficult or expensive.

27. LOAD CAN BE TRANSFERRED BY PILE
TO THE GROUND BY 2 WAY THAT IS:
End Bearing Piles OR
- Pile will transmit load into the firm soil layer of the ground such as rock, gravel, very dense sand
b) Friction Piles
- Pile transmit the load from the structure to the penetrable soil by means of skin friction or cohession between the soil & the embedded surface of the pile.

28. There 2 type of End Bearing Piles That is Preformed Timber Pile & In-Site-Reinforced Concrete Pile

29. Friction Pile May Be Used To Support DownWard Load

30. TYPES OF PILES a) Concrete Piles i) Cast-In-Place Concrete Piles
ii) Precast Concrete Piles
iii) Drilled Shafts
b) Steel Piles
I) H-Piles ii) Cylindrical iii) Tapered
c) Timber Piles
d) Composite Piles

31. CAST IN PLACE CONCRETE PILES
Formed by driving a cylindrical steel shell into the ground to the desired depth and cavity of shell is filled with fluid concrete.
The steel shell doesn’t contribute to the load transfer capacity of the pile.
It’s purpose is to open a hole in a ground and keep it open to facilitate the construction of concrete pile. (same function as formwork)
Vigilant quality control & good construction practice are necessary to ensure the integrity of cast-in-place piles.

32. Among the advantages of Cast-In-Place
Concrete are as follows:
Can sustain hard driving
Resistant to marine organism
Easily inspected
Length can be changed easily
Easy to handle and ship

33. PRECAST CONCRETE PILES
Usually have square/circular/octagonal cross sections.
Fabricated in a construction yard from reinforced or pre-stressed concrete.
Disadvantages of this pile are problems in transporting long piles, cutting and lengthening.
It has higher capacity than timber piles.

34. STEEL PILES It comes in various shapes & sizes
Steel H-Piles are rolled steel sections
Steel pipe piles are seamless pipes that can be welded to yield lengths up to 70m.
They are usually driven with open ends into the soil.
A conical tip is used where the piles have to penetrate boulders & rocks.
However it needs to be treated before embedded in corrosive environment.

35. TIMBER PILES Have been used since ancient times
Length of timber piles depends on types of trees used to harvest the piles,
Common length are 12m
It is susceptible to termites, marine organisms and rot within zones exposed to seasonal changes.
Eventhough it’s cheaper but it has low capacity and can’t take hard driving.

36. TYPES OF PILE CHOSEN DEPENDS ON FOLLOWING FACTORS:
What type of pile is readily available
Location & type of structure (magnitude of loading)
Ground Condition (soil type)
Cost
Durability

37. TYPES OF PILE CONSTRUCTION
Displacement Piles
- It cause the soil to be displaced radially as well as vertically as pile shaft is driven or jacked into the ground.
b) Non Displacement Piles
- It cause the soil to be removed and the resulting hole filled with concrete or a pre cast concrete pile is dropped into the hole and grouted in.

38. Displacement Pile

39. Replacement Pile / Non Displacement Pile

40. TYPES OF DISPLACEMENT PILES:
Can be classified into different types base on how they are constructed and how they are inserted.
There are 3 types as follows:
Totally Preformed Displacement Piles
(precast concrete or steel pile)
Driven & Cast-In-Place Displacement Pile
Helical Cast-In-Place Displacement Piles

41. Totally Preformed Displacement Piles
- Precast Concrete or Steel Pile
b) Driven & Cast-In-Place Displacement Pile
- This type of pile can be of 2 forms.
- The first involves driving a temporary steel
tube with a closed end into the ground to
form a void in the soil which is then filled
with concrete as the tube is withdrawn.
- The second type is the same except the steel
tube is left in place to form a permanent
casing.

42. c) Helical Cast-In-Place Displacement Piles
- This type of construction is performed using a special type of auger.
- The soil is however compacted, not removed as the auger is screwed into the ground.
- The auger is carried on a hollow stem which can be filled with concrete, so when the required depth has been reached concrete can be pumped down the stem & the auger slowly unscrewed leaving the pile cast in place.

43. METHOD OF INSTALLATION
Dropping Weight or Drop Hammers
- commonly used method of insertion of displacement piles
Diesel Hammers
- Most suitable to drive pile in non cohesive granular soil
Vibratory Hammers or vibratory method of pile driving
- very effective in driving piles through non cohesive granular soil
Jacking Method Of Insertion

44. Diesel Hammer
Rapid controlled explosions can be produced by the diesel hammer.
The explosions raise a ram which is used to drive the pile into the ground.
Although the ram is smaller than the weight used in the drop hammer the increased frequency of the blows can make up for this inefficiency.
This type of hammer is most suitable for driving piles through non-cohesive granular soils where the majority of the resistance is from end bearing.

45. Vibratory Method of Pile Driving
Vibratory methods can prove to be very effective in driving piles through non cohesive granular soils.
The vibration of the pile excites the soil grains adjacent to the pile making the soil almost free flowing thus significantly reducing friction along the pile shaft.
However the large energy resulting from the vibrations can damage equipment, noise and vibration propagation can also result in the settlement of nearby buildings.

46. Pile Driving Rig - raise and temporarily support the pile that being driven and to support the pile hammer.

47. Pile Driving Rig

48. Dropping Weight / Drop Hammers
A weight approximately half that of the
pile is raised a suitable distance in a guide
and released to strike the pile head.
When driving a hollow pile tube the
weight usually acts on a plug at the bottom
of the pile thus reducing any excess
stresses along the length of the tube during
insertion.

49. Pile Installation Using Drop Hammer

50. Jacking Method Of Insertion
Jacked Piles are most commonly used in
underpinning structures
By excavating underneath a structure short
lengths of pile can be inserted and jacked
into the ground using the underside of the
existing structure as a reaction.

51. Jacking Method Of Insertion

52. NON DISPLACEMENT PILES
THERE ARE 4 TYPES THAT IS:
Small Diameter Cast-In-Place
Large Diameter Cast-In-Place
Partially Preformed Piles
Grout or Concrete Intruded Piles

53. PIERS It’s a vertical bridge support.
It’s a foundation for carrying a heavy
structural load which is constructed in site
in a deep excavation.

54. Among the things to be taken in consideration
during construction of pier are as follows:
Drilling through wet or caving soils may need use of temporary steel casing. May also require the use of a tremie & a pump to dewater the hole & place concrete. This is more expensive and require a large diameter hole.
For the purpose of reinforcing, it’s difficult to get bars to the full depth of the pier with the proper concrete cover in deep holes.Use centralizes. Use large diameter bars versus more bars.

55. c) Don’t leave holes open for any length of time even in dry condition
c) Don’t leave holes open for any length of time even in dry condition. Cuttings fall in or etc. Have concrete on site and fill right after drilling and cleaning.

56. Pier

57. Pier

58. Pier

59. Pumping Water Out Of The Hole For The Excavation
Of The Pier

60. Constructing The Pier Framing

61. Completed Pier Framing
Post Footing & Detail

62. Ramp Is Installed
Ramp Is Bolted

63. Floor Decking
Installation
Completed Pier

64. CAISSON FOUNDATION

65. WHAT IS CAISSONS? It’s a prefabricated hollow box or cylinder.
It is sunk into the ground to some desired
depth and then filled with concrete thus
forming a foundation.
Most often used in the construction of bridge piers & other structures that require foundation beneath rivers & other bodies of water.
This is because caissons can be floated to the job site and sunk into place.

66. Basically it is similar in form to pile
foundation but installed using different way
used when soil of adequate bearing strength
is found below surface layers of weak
materials such as fill or peat.
It’s a form of deep foundation which are
constructed above ground level, then sunk to
the required level by excavating or dredging
material from within the caisson.

67. A caisson foundation consists of concrete
columns constructed in cylindrical shafts
excavated under the proposed structural
column locations
Caissons are drilled to bedrock or deep into
the underlying strata if a geotech eng. find the
soil suitable to carry the building load.

68. It’s created by auguring a deep hole in the
ground.
Then, 2 or more ‘stick’ reinforcing bar are I
inserted into and run the full length of the
hole and the concrete is poured into the
caisson hole.
The caisson foundations carry the building
loads at their lower ends, which are often
bell-shaped.

69. Caissons

70. TYPES OF CAISSONS Box Caissons Excavated Caissons Floating Caissons
Open Caissons
Pneumatic Caissons
Sheeted Caissons

71. Reinforced Concrete Caissons

72. Caissons

73. Caisson As One Of The Elements In This Structure

74. THE END