Abstract: The blasting seismic wave is simplified reasonably. Based on wave function expansion method, the dynamic stress concentration factor equation of tunnel surrounding rock and lining under the blasting seismic wave is deduced in infinite rock. Combining with a typical case, the influences of the main frequency of the blasting seismic wave, geometric parameters and the physico-mechanical indices of tunnel surrounding rock and lining on dynamic stress concentration factor in the different positions of tunnel are analyzed. The analytical results show that the trend of dynamic stress concentration factor of different direction stresses with the main frequency of the blasting seismic wave are different at different positions. The dynamic stress concentration factor caused by the blasting seismic wave with low main frequency of the blasting seismic wave is larger, which is unfavorable for blasting vibration resistance. The influence trend of tunnel geometric parameters on the dynamic stress concentration factor of tangential stress of tunnel surrounding rock and lining is different. The elastic modulus of tunnel lining has a greater effect on dynamic stress concentration factor than the Poisson’s ratio. The tunnel surrounding rock with larger Poisson’s ratio have the effect of blasting vibration resistance, but the effect is limited.

Key words: blasting seismic wave, wave function expansion method, tunnel surrounding rock, tunnel lining, dynamic stress concentration factor (DSCF)