Abstract:
The loads of the structures are transferred to the soil by foundation. Foundations of structures are
subjected to different modes of loading. For weak soil and heavy construction of structures pile
foundation are better choices. Pile foundations are usually used in harbor structures, bridges, high
rise structures and chimneys where both axial and lateral loads are expected to act on the
foundation. For the improvement of lateral capacity, many researchers have developed different
techniques. The new improvement techniques have been found costly. Under-reamed piles have
mechanically formed enlarged base that forms an inverted cone and can only be formed in stable
soils. They are used in normal ground condition also where economics are favorable. Under reamed piles having one or more bulbs at specified locations along their depths have been
extensively used in India to support a wide variety of structures in almost all types of soil strata. In
many situations, these piles are also required to resist considerable amount of lateral loads besides
vertical compressive and uplift loads. However, the behaviour of these piles under lateral loads has
not been properly investigated Used to increase the load-carrying capacity of pile foundation under
compression, tension, and lateral loading with least deflection compared to other piles.
This thesis work is to study the behavior of under-reamed piles under cyclic loading. The
numerical analysis is done by PLAXIS-3D software. The analysis is done on under-r-eamed piles
in sand. The study focuses on the lateral capacity of under-reamed pile under the influence of
differentsize and geometry of under-ream. The study is done under lateral loading condition on
under-reamed piles in sand.
