Abstract: Three different situations of 7521 coal face tunnel driving of Yaoqiao coal mine were simulated using UDEC. Numerical results show that 7521 tunnel surrounding rock mass has once mining influence and little effects produced to tunnel when driving ahead of mining; 7521 tunnel surrounding rock mass has twice mining influence, and the second mining occurred after first mining when mining ahead of driving, the influence to tunnel is much greater; under the condition of driving and mining at same time, 7521 tunnel surrounding rock mass has twice mining influence, but the stress superposition would produced as effected by twice mining when the first was still unsteady, so the influence to tunnel was great. Site mine pressure situation and tunnel surface displacement curves show that driving ahead of mining scheme was most beneficial to the stability of tunnel.

Key words: Numerical simulation, Kinetic pressure, Floor heave