Simulation geometric model of soft soil microstructure is the premise and foundation for micro numerical simulation of soft soil. According to the void ratio and the percent contents of each fraction obtained from conventional soil test

the Monte Carlo method is applied to generate a certain amount of random polygon elements to represent the various structure elements and pores of soil microstructure

the random geometric model of soft soil microstructure is established by distributing these polygons into a given size region randomly. By applying this method to the microstructure simulation modeling for the soft soil samples in a certain highway engineering in Guangdong Province

the result shows that the simulation geometric model has certain similarity with the actual microstructure image of the soil sample

the feasibility of proposed method is verified.