Abstract: The failure mode of tunnels in the jointed rock mass has a close relationship with the rock joint characteristics. Based on a jointed rock mass model of a tunnel project in Fujian Province, the discrete element method was utilized to establish the failure mode of tunnels in jointed rock mass with various dip angels, rock fragment strengths, joints strengths, buried depths and joint spacing. The following results can be concluded: 1) the failure direction of tunnel in jointed rock mass is governed by the dip angle of the joints; 2) the rock fragment strengths, joints strengths and buried depths have an effect on the degree of damage of tunnels in jointed rock mass; 3) the joint spacing also might have an effect on the degree of damage of the tunnel.

Key words: Jointed Rock Mass, Tectonic Stresses, Tunnel Engineering, Failure Modes, Discrete Element Method