Analysis of Dynamic Compaction of Loose Soils Under Impact Loads

Dynamic compaction has become a popular method world-wide for deep improvement of loose soils in recent years. The method involves the repeated application of high-energy impacts on the soil surface using tampers weighing 10-20 Mg, dropping from heights of 10-20 m, compacting the soil strata to a considerable depth. Previous analytical methods have been used to investigate the effectiveness of dynamic compaction of loose soils, most of which were based on a rigid tamper striking a vertical soil column represented by springs, masses and dampers. This study analysed the dynamic compaction of loose soils under impact loads numerically, using ABAQUS© to generate response to rigid-body impacts of an axisymmetric elasto-plastic finite element (FE) representation of the soils. The analysis also included the stiff plug formed under the treatment area. Various comparisons were made in terms of the plug depth, the compression wave propagation, peak vertical particle accelerations with depth and the mass penetration. The peak vertical particle velocities at ground surface within some 50 metres were computed for estimation of environmental disturbance in the vicinity