Abstract: The tunnel named 2# cross-hole of Weijiadi coal mine in Gansu province influenced by both of tectonic stress and mining-induced stress is damaged,which shows as large roof subsidence,huge two-side wall displacement and serious floor heave.After repairing for many times,the damaged support has influenced the production and the safety.By the numerical simulation software FLAC3D,based on the analysis of the geological condition and the previous repairing supporting and referring to the pre-existing relative information,one model of the supporting program is built to calculate the safety of the supporting program that is to control floor heave by strengthening roof and sides of the tunnel.The calculation results indicate that the deformation of roof and sides and the floor heave are controlled effectively with the supporting program.The field monitoring results showed that for the soft rock tunnel,the supporting program of strengthening the intensity of roof and sides of the tunnel can control the floor heave in some way.This supporting program is reasonable and feasible,and can meet the requirement of the tunnel safety. Floor heave|FLAC,Numerical simulation|Strengthening|Field monitoring|Safety