Numerical Study on Interference of Surface Strip Footings Resting on Stiff Clay

Abstract

In the present study, the interference effects of two closely spaced strip footings on the surface of stiff clay were investigated. The effect of interference on characteristic behaviour like bearing pressure, settlement and tilt is observed using two-dimensional plane strain analysis. Finite element analysis software PLAXIS 2D is used for this. The behaviour of individual footing on stiff clay is first established. Parametric study is done by varying the width of footing and the spacing between the footings. The results are presented in terms of efficiency factors, which are defined as the ratio of settlement or bearing pressure of interfering footing to that of the isolated footing. The effect of interference is particularly noticeable in terms of settlement. Maximum settlement and tilt occur at a spacing 1.5B irrespective of the footing width. Effect of shear keys placed beneath the footings at different locations beneath the footing and the interference of such footings were also studied. It is found that the presence of shear keys has a significant effect on the interference between the footings, compared to without the shear keys. © 2020, Springer Nature Singapore Pte Ltd.