Optimizing the Bearing Capacity of Pile Foundation in Clay

Abstract

AbstractThe ultimate collapse load (bearing capacity) of constant cross-section pile, tapered pile, and under-reamed pile in clay is estimated with the help of lower bound finite element limit analysis. Four different types of piles are considered: constant cross-section pile of smaller diameter, constant cross-section pile of larger diameter, tapered pile, and under-reamed pile. A comparison of the ultimate collapse load of four different piles is made by considering variables such as pile length, shaft diameter, taper angle, and bulb to shaft diameter ratio. For a given pile length and volume, the ultimate collapse load of the under-reamed pile is significantly higher than constant cross-section pile and tapered pile. The percent increase in the ultimate collapse load of the under-reamed pile is significant for a smaller length of the pile. For piles of a given length, the ultimate collapse load of under-reamed pile increases significantly compared to constant cross-section pile and tapered pile, for an increase in the bulb to shaft diameter ratio. From this study, it is concluded that among constant cross-section, tapered, and under-reamed pile, under-reamed pile gives the highest bearing capacity.KeywordsPile foundationClayBearing capacityLimit analysisPlasticity