ABSTRACT
Dynamic compaction (DC) has gained significant popularity in the last few decades as an effective ground improvement technique for densification of loose granular soils. The objective of the paper is to examine the influence of tamper geometry on the response of underlying deposits for improving the efficiency of DC process in the field. An experimental set-up is designed and developed for the above purpose, and the advantages of the actuator over existing test-setups are discussed. Physical model tests are subsequently carried out with the developed actuator at earth’s gravity on loose dry sandy soil using circular and conical based tampers. The degree and depth of improvement due to DC is assessed in each case using Geo-PIV on images captured during experimentation. The pattern of propagation of energy waves though the soil mass plotted in terms of displacement vectors and contours varied considerably depending on tamper shape, and for a given drop height and tamper mass, the use of conical tamper resulted in larger extent of influence zone (of the order of 16%) as compared to flat based tamper. Further, the volume of crater induced by conical tamper was observed to be 18% more than that of conventional flat based tamper.
