Behavior of two parallel strip footings on a sand cushion over clay

Abstract EN

In this paper, the behavior of two parallel strip footings resting on the surface of a semi-infinite clay is investigated.

The effect of stress interference on bearing capacity and settlement are studied using the finite element program PLAXIS 2D.

The clay is stimulated using the Mohr-Coulomb soil model that follows linear-elastic perfectly plastic behavior.

A parametric study is performed for different clear spacing between the footings.

The paper also investigates the effect of existence of a sand cushion as well as the existence of a layer of geogrid inside the cushion below the clay; on the stress-settlement relationship, and the bearing capacity of soil.

The results are presented in terms of non-dimensional factors defined as the ratio of settlement and bearing capacity of interfering strip footings to that of a single strip footing resting over the same soil conditions.

The study shows that the bearing capacity decreases with the decrease in clear spacing between the parallel strip footings, while the settlement is found to increase.

The results of this paper may give designer engineers to include the effect of spacing between strip footings in the design according to a given value of bearing capacity.