Bearing Capacity of Piles in Non-homogeneous Clay Using Conic Programming

Abstract

By using the lower bound finite elements limit analysis, this paper presents a methodology to evaluate the bearing capacity of piles in cohesive soils. The non-homogeneous nature of soil has been assumed for which the cohesion increases linearly with depth. An axisymmetric formulation, comprising of a planar domain with a mesh of three noded triangular elements has been adopted. Here, Mohr–Coulomb (MC) yield criterion has been employed. The yield criterion is expressed in terms of three quadratic constraints so that the problem can be solved using second-order cone programming (SOCP). Bearing capacity factors have been generated as a function of (i) height to radius ratio of the pile, (ii) rate of increase of cohesion and (ii) roughness of base and shaft of pile. The results computed from the analysis have been compared thoroughly with that reported in literatures.