Dynamic compaction of loose sand deposits

Abstract

A theoretical framework based on one-dimensional wave equation model in conjunction with standard penetration test (SPT) results for the dynamic compaction analysis of loose sand deposits is presented. The wave equation model properly simulates the dynamic interaction between the pounder and the soil, the punch-through failure mechanism as well as the propagation of stress waves in the soil. Two reported case histories are analyzed and it is demonstrated that the pounder penetration, the degree and depth of soil improvement can be reasonably predicted using this model. The computed results of soil improvement are found to agree closer to those estimated based on the correlations of Skempton (1986) and Peck and Bazaraa (1969). The correlation of Gibbs and Holtz (1957) appears to lead to an over-estimation of the relative density of sand after dynamic compaction. It is believed that the theoretical framework discussed in this paper can provide a better understanding of the dynamic compaction process and may in due course lead to more cost-effective means of designing dynamic compaction work.