**The
use of pile foundations is inevitable during following conditions:**1. At the
time when the strata at or just beneath the ground surface is greatly
compressible and very weak or loose for carrying the load transferred from the
structure above.
3. When the plan of the structure is irregular relative to its outline and load
distribution. This may lead to the unpleasant non-uniform settlement when the
shallow foundation is constructed. Thus, a pile foundation eliminates
differential settlement.
5. The pile foundations are perfect for transmission of different structural
loading/forces via deep water to the firm stratum below.
7. The pile foundations are proficiently used to withstand the horizontal forces
as well as supports. The vertical forces/loads in the earth retaining structures
and tall structure which are subjected to horizontal forces of wind and
earthquake.
9. The plies are extremely useful when the soil conditions are in very
loose/weak conditions that a washout, erosion and scour of soil underneath leads
to the collapse of shallow foundations.
11. The piles are used for the foundations of some structures, such as
transmission towers, off-shore platforms, which are subjected to uplift.
13. In expansive soils like black cotton soil, that swells or shrinks when the
ware content varies, the piles are used to transfer the load below the active
zone.