Foundation Bearing Capacity Estimation on Rock-Mass Using Hoek–Brown Failure Criterion and Equivalent Mohr–Coulomb Parameters

Abstract

In general practice, the shallow foundations serve as economic and reliable solution to support high-rise buildings, bridges, and other heavy structures constructed on rock-mass. The aim of the present study is to simulate fractured homogenous rock-mass in finite element framework and to obtain bearing capacity of a strip footing. For this purpose, both displacement-based finite element (FE) analysis and finite element limit analysis (FELA) are carried out and results are compared. Finite element models of the flat rock-mass with supported foundations are developed in finite element package ABAQUS. The foundation is modeled using two-node cubic beam (B23) and rock-mass using plane-strain quadratic (CPE8R) element with reduced integration, having “Equivalent Mohr–Coulomb parameters.” Models with the same rock and foundation properties are modeled in OptumG2 based on FELA to obtain the upper-bound (UB) and lower-bound (LB) solutions with a constitutive model based on the Hoek–Brown failure criterion. The comparative study illustrates the critical issues that arise while implementing the failure criterion using the equivalent Mohr–Coulomb parameters, particularly in bearing capacity estimation, where the overburden pressure is low. © 2021, Springer Nature Singapore Pte Ltd.