2. BEARING CAPACITY OF SOIL
GUIDED by:- GAURAV GOHIL
SR. NO. NAME ENROLLMENT NO.
1 PRAJAPATI MITESH P. 151240106064
2 PRAJAPATI NILESH D. 151240106065
3 PRAJAPATI TIRATH A. 151240106066
BRANCH : CIVIL
3. What is Soil Bearing Capacity?
• The Bearing Capacity of Soils is perhaps the most
important of all the topics in soil engineering.
• In geotechnical engineering, Bearing Capacity is
the capacity of soil to support the loads applied
to the ground. The bearing capacity of soil is the
maximum average contact pressure between
the foundation and the soil which should not
produce shear failure in the soil.
• Soils behave in a complex manner when loaded
so, it is important to know the bearing capacity of
4. Why is Soil Bearing Capacity required?
• The stability of foundation depends on:
1) The bearing capacity of the soil beneath the
2) The settlement of the soil beneath the `
• There are, therefore, two independent stability conditions to be
fulfilled since the shearing resistance of the soil provides the bearing
capacity and the consolidation properties determine the settlement.
5. Important Terminologies related to Soil
• Ultimate Bearing Capacity (qu)
The ultimate bearing capacity is the gross
pressure at the base Of the foundation at
which soil fails in shear.
• Net ultimate Bearing Capacity (qnu):
It is the net increase in pressure at the
base of foundation that cause shear failure of
6. • Net Safe Bearing Capacity (qns):
It is the net soil pressure which can be safely applied
to the soil considering only shear failure.
• Gross Safe Bearing Capacity (qs):
It is the maximum pressure which the soil can carry
safely without shear failure.
7. • Net Safe Settlement Pressure (qnp):
It is the net pressure which the soil can carry without
exceeding allowable settlement
• Net Allowable Bearing Pressure (qna):
It is the net bearing pressure which can be used for design
8. METHODS OF INCREASING SOIL BEARING CAPACITY OF BLACK COTTON SOIL
• 1) Increasing Depth of Foundation:
In granular soil the bearing capacity
increases with the depth due to the
confining weight of overlying
• 2 ) Chemical Treatment:
In this treatment certain chemicals
are grouted in the place of cement
grout. The chemical used is such that
it can solidify and gain early strength.
9. • 3) Grouting:
Bore holes in sufficient numbers are driven in the
ground and cement grout is forced through
these under pressure
Due to which the bearing capacity of soil is
• 4) Compaction of soil:
Due to the compaction of soil the bearing
capacity of the soil increases resulting in
reduction in resting settlements
10. 5) Drainage of soil:
Due to the presence of water
in the soil the bearing
capacity of the soil is
decreased hence by draining
out water the void ratio is
improved resulting in higher
11. 6) Confining the soil:
• sometimes the safe bearing pressure of
the soil is low because of settlements
resulting due to the lateral movement of
loose granular soil.
• Such a tendency of lateral movement
can be checked by confining the soil ,
outside the perimeter of foundation area ,
by driving sheet piles , thus forming an
enclosure and confining the soil.