Seismic bearing capacity of strip footing above cavities in rock masses

Abstract

AbstractThis paper presents a novel approach for investigating the seismic bearing capacity of strip footings overlying cavities in rock masses using adaptive finite element limit analysis (FELA) combined with nonlinear programming (NLP). The generalized Hoek-Brown failure criterion is employed to describe the strength of the rock mass, which is directly incorporated into the FELA program. The feasible arc interior point algorithm (FAIPA) is utilized to solve the optimization models, and to enhance the convergence speed of the NLP algorithm, a new imprecise step search algorithm is proposed. Based on the FELA method, the bearing capacity of strip footing on a rock mass without voids and the dimensionless reduction factor are determined. The computed results are presented in tables and charts, and the impacts of geometric parameters and material properties on the reduction factor are thoroughly investigated. Furthermore, failure modes associated with different parameters are discussed, and a design procedure is proposed for practical engineering applications.