Abstract: Previous simulation methods of the splitting diffusion of self-expanding polymer materials in soils are not complete yet. This paper develops a new, preliminary simulation method for simulating the splitting compaction effect of polymer on soil. This method uses the extended finite element method (XFEM) to solve numerically the regional soil medium, and adopts a modified Cam-clay model to describe the mechanical characteristics of the soil. And it calculates slurry expansion pressure acting on the surfaces of a soil fracture iteratively using the relationship of polymer density versus confining pressure. We realize numerical solutions of the process of crack propagation in the soil, and verify them against experimental data. Example analysis shows that the method is applicable and effective in the simulation of the soil’s crack initiation process, propagation direction, and grout vein thickness variation under the expansive force, and it gives the distribution characteristics of deformation modulus, void ratio, stress field, and density field over the soil zone around a crack, thus laying a basis for further study of the splitting compaction mechanism of expansive polymer grouting material in soil.

Key words: polymer grouting, extended finite element method, modified Cam-clay model, splitting mechanism, compaction effect