Seismic bearing capacity for strip footings above voids in cohesive-frictional soils

Abstract

In this article, the seismic bearing capacity for strip footings above square voids in cohesive-frictional soils is presented. A numerical study is performed by using adaptive finite element limit analysis (AFELA), and the pseudostatic approach is employed to consider the earthquake loadings. Both the upper bound (UB) and lower bound (LB) of the seismic bearing capacity for the strip footing are obtained, along with the relative errors, which are found within 8% or less. The results are presented in the form of design tables and charts to be used by designers and practicing engineers. The effects of the location of the voids, the dimensionless strength ratio c/( γB), the soil internal friction angle ϕ, and the horizontal seismic coefficient kh on the seismic bearing capacity are examined. In addition, the failure mechanisms are also discussed, and comparisons with previous studies of static nature are conducted.