Abstract:

The stress and deformation characteristics of soil mass nearby ground fissure were studied by a large-scale model test of ground fissure activity under the environment of Xi’an typical strata. It is shown that in the hanging wall of ground fissure the negative additional stress in soil mass is induced by the ground fissure movement and so stress in soil decreases; but in the foot wall the positive additional stress in soil mass is created and stress in soil increases, and the more far distance from ground fissure, less additional stress caused by ground fissure movement. Meanwhile, the bilateral soil deformations of ground fissure appear step mutation; and the range of soil deformation is larged from deep strata to shallow strata; and deformation zone in hanging wall is larger than that in footwall. Soil stress distrbution nearby ground fissure in space can be divided into 4 zones, i.e. the initial stress zone of footwall, stress increasing zone, stress decreasing zone and initial stress zone of hanging wall; and the range of stress decreasing zone is 1.5 to 2 times that of stress increasing zone. Also the soil settlement deformation neraby ground fissure can be divided into 3 zones, i.e. the stable zone of footwall, differential settlement transitional zone and stable zone of hanging wall; and the range of differential settlement zone in hanging wall is 2 times that of the footwall of ground fissure.

Key words: soil mechanics, ground fissure, model test, soil stress, settlement deformation, spatial distrbution characteristics