Mitigating the seismic settlement of foundations on sand by ground improvement techniques

Geotechnical design of shallow foundations on clean fine sands often requires provisions for earthquake-induced settlements. In this regard, there have been many investigations on the volume-change behaviour of fine sands during dynamic and cyclic loading, and different methods have been developed to estimate ground settlement. However, less attention has been given to the role of ground improvement in reducing earthquake-induced settlements. This paper focuses on Anzali sand, which is representative of most sands found in the northern Iran, a region subject to high seismic activity. This sand was studied with the aid of physical modelling in the laboratory, and three different soil stabilisation techniques were applied to improve its stiffness and strength against volume change. Investigations revealed that among these methods, the cement treatment technique has an appreciable effect on the mitigation of seismic settlement.