Abstract: According to the problem of larger surface subsidence caused by mining under bridge and railway in Zhaogu No. 2 Coal Mine, used the mechanical theory of soil, we analyzed the movement and deformation characteristics of soil in the mining area. Through the normalized processing of the soil mechanical test results, we analyzed the changing laws of soil mechanics parameters and got the relation curves between the rate of soil dry density and soil mechanics parameters disturbance rate, and the relation curves between the rate of soil mechanics parameters disturbance change rate and disturbance rate.