This presentation provides information about shallow foundations. It defines a foundation as the part of a building below ground that transfers the building's weight to the soil. Shallow foundations are placed immediately below the structure and include spread footings, combined footings, mat/raft foundations, and grillage footings. Spread footings support columns and walls, and come in types like wall, column, and inverted arch footings. Combined footings support two or three close columns. Mat foundations consist of a thick concrete slab covering the entire bottom area. The presentation discusses the advantages of shallow foundations like quick construction and lower cost, and disadvantages such as limitations with expansive soils.
3. GROUP MEMBERS NAME & ID
SAYED KOUSAR KHAN M21415121538
MD.LUTFOR RAHMAN M21515121165
SHAHED KARIM MULLICK M214151211027
4. What is foundation ?
Fig: Foundation
Foundation: Foundation is
part of a building, usually
below the ground, that
transfers and distributes
the weight of the building
onto the ground such that
the compressive stresses
do not exceed the bearing
capacity of the soil
7. The various types of shallow
foundations are :
(a) Spread footing
(b) Combined footing
(c) Mat or Raft foundation.
(d) Grillage footing
(e) Eccentrically loaded footing
8. Spread footings
Spread footings are s
tructural members us
ed to support colu
mns and walls and t
o transmit and di
stribute their loads to
the soil.
10. Combined footings
Combined footings
usually support two
columns, or three
columns not in a row. Co
mbined footings are used
when tow columns
are so close that single fo
otings cannot be used
or when one column
is located at or near a pr
operty line.
11. Raft Foundation
Foundation which consists of th
ick reinforced concrete slab cove
ring the entire area of the bot
tom of the structure like
a floor.
This foundation was invented by
John Root at Chicago in 19th
century
12. Advantages of shallow foundation
It is a quick process compared to others in the
construction work.
This type of foundation is also economically
cheaper than any other foundations.
Though there are some limitations in mat
foundation still it is economical in some cases
13. Advantages of shallow foundation
It can resist ground water absorption.
The damage due to earthquake is lesser than any other
type of foundation.
It consists of a reinforced concrete slab which is more
thicker than footing foundation.
It prevents unequal settlements.
14. Disadvantages of shallow foundation
Spread footers being installed too shallow, often times
just 23 feet below. A foundation, which does not
eliminate the effects of expansive soils.
Foundation repair will last longer than a week as the
excavations are made and the concrete will have to be
cured before the holes can be refilled.
15. Disadvantages of shallow foundation
A huge amount of earthwork is to be
done in Mat foundation.
Groundwater may come out when the
earthwork is done.
Limited to dealing with point loads