Hybrid Numerical Investigation on Soil-Hammer Interaction during Dynamic Compaction

Abstract

To investigate the mechanism of hammer-soil interaction under the action of dynamic compaction (DC) on a coarse-grained soil foundation, based on the theory of projectile penetration, the continuous-discrete coupling method is used to simulate the hammer-soil interaction process with different hammer shapes and different particle radii. The physical phenomena and mechanical parameters presented by the hammers and soil particles are quantitatively analyzed. The results show that the penetrating ability of the hammer is proportional to its lateral extrusion shearing ability and inversely proportional to its vertical extrusion capacity. The convex-bottomed hammer has the maximum penetration and lateral extrusion capability, the flat-bottomed hammer has the smallest penetration ability and the lateral extrusion capacity, and the concave-bottomed hammer has a penetration and lateral extrusion ability between those of the convex- and flat-bottomed hammers. The impact strength and vertical disturbance of the flat-bottomed hammer are the strongest, followed by the concave-bottomed hammer and the convex-bottomed hammer. In addition, it is found that the smaller the particle size of the coarse-grained soil is, the greater the depth of the crater formed and the smaller the contact force and the influence range of vertical disturbance. These research results reveal the interaction mechanisms of different hammer types and coarse-grained soil, which is expected to provide reference and guidance for the design and construction of coarse-grained soil foundations enhanced by DC.