Research on vibration reduction effect of blasting shock-absorbing holes in tunnel
To explore the influence of different arrangement methods of shock-absorbing holes on the vibration reduction effect during tunnel blasting,the ANSYS/LS-DYNA software was used to construct a numerical model of tunnel blasting.The vi-bration reduction effect of four working conditions,including without shock-absorbing holes,conventional shock-absorbing holes,encrypted shock-absorbing holes,and enlarged shock-absorbing holes,was compared and analyzed from the change in surrounding rock vibration velocity,stress,and damage.The results show that after increasing the aperture of shock-absorbing hole,the vibration reduction efficiency in terms of vibration velocity and stress is relatively high,reaching 27.7%and 27.9%,respectively.The setting of shock-absorbing holes can effectively hinder the propagation of blasting stress and the ex-pansion of damage cracks.The enlarged shock-absorbing holes have a better hindering effect,reducing the stress radiation ra-dius and damage radius of the surrounding rock during tunnel blasting by half.The hindering effect of conventional and en-crypted shock-absorbing holes is relatively small.The research results can provide a reference for optimizing the arrangement methods of shock-absorbing holes in the drilling and blasting construction of tunnels.