As an efficient foundation reinforcement technology

dynamic compaction technology has been widely used in various engineering constructions. However

most related theoretical research mainly focus on the tamping at a single location

and the interaction between adjacent tamping points under tamping at several locations simultaneously is rarely studied. In order to investigate the reinforcement impacts of multi-tamping under different arrangement forms of tamping location

the geometric nonlinear finite element method for large deformation and the constitutive model of “cap” in the framework of LS-DYNA are applied to analyze the degree of soil compactness under strong tamping at multi-locations. Firstly

based on the tamping experiment at a actual situation of site construction

the rationality of the model is verified by comparing the numerical results with the measured data for the lateral displacement in the soil around the tamping points. Moreover

considering two common arrangements of tamping points (i.e. rhombus-grid pattern and square-grid pattern)

numerical simulations are carried out on the dynamic construction process

and compaction degree of the soil under different layouts of tamping points are studied. The results show that the compacted area between adjacent tamping locations is susceptible to multi-tamping effects

and the reinforcement degree of soil near the subsequent tamping location is better than that near the previous tamping location. Besides

the reinforcement of soil is better in regions applying rhombus-grid tamping points compared with that of square-grid pattern. In addition

by using the depth of the crater and the effective reinforcement depth

the soil affected by the strong tamping can be divided into three parts: the dilatation zone

the strong reinforcement zone and the slightly disturbed zone.