Numerical analysis of the response laws of roadways with different sections to blasting seismic wave

In order to effectively reduce the adverse effects of blasting seismic waves on existing roadways, reasonable measures should be taken based on the actual response characteristics of roadways to the blasting seismic wave.The response of roadway walls with different sections and surrounding rock mass to the normally incident blasting seismic wave was studied using numerical simulation method.The results show that the vibration response of roadway with composite section is approximately equal to the superposition of which with the corresponding basic section under the same impact.The vibration velocity magnification effect of roadway wall with the section containing straight wall is stronger than that of the circular or elliptical ones, and its spatial distribution variability along the wall of vibration velocity is greater.Vibration amplification effect mainly occurs in rock mass from the distance of 1 times the height of the tunnel wall, and the closer from the wall, the more serious vibration amplification is.The vibration response of roadway wall is remarkably sensitive to the change of vibration frequency of blasting seismic wave.The magnitudes and spatial distribution of vibration response change with the variety of vibration frequencies.Differences of vibration response caused by geometric properties of section increase with the increase of vibration frequencies.