Abstract:

A numerical model of tunnelsoil is established by means of PFC2D (Particle Flow Code) discrete element software, so as to simulate the ground settlement induced by tunneling. The study results show that: 1) The PFC2D can be considered as an effective way to simulate the tunnel excavation. 2) The effect of soil arch is proportional to the ground loss. 3) The shear strain rate of sandy strata decreases gradually from the medial axis to the side and increases gradually from deep soil to shallow soil during tunneling. The analysis results can provide theoretical reference for study on ground settlement induced by tunneling in sandy strata.

Key words: sand strata, tunneling, settlement, PFC2D, soil arching effect, ground loss rate