Deformation Response of Tunnel Lining in Geological Area of Coal Seam Group Caused by Explosion Stress Wave

AbstractTo study the influence of drilling and blasting on the deformation of the tunnel lining in a multimedium surrounding rock section, this paper constructs the deformation calculation theory of the explosion stress wave of the tunnel lining. We select single-medium surrounding rock, multimedium surrounding rock, different explosion accelerations, and different surrounding rock grades as research variables and analyse in depth the causes of the deformation response of the tunnel lining. It is found that the stress wave causes more damage to the surrounding rock closer to the explosion point, and the disturbance to the surrounding rock increases with the increase of the acceleration of the explosion stress wave. And the better the surrounding rock grade, the more obvious the creep effect formed by the explosion stress wave, and the more damaging the stress wave propagation is to the tunnel lining. After the stress wave propagation medium changes from soft to hard, the energy will produce a “nest effect” at the interface between the two media, and the energy will accumulate briefly at the interface. When a certain amount of energy has accumulated, it propagates into the hard medium in an excited state, which causes large vibration of the tunnel lining in the soft medium area. The stress wave propagation medium changes from hard to soft, and the excessive energy in the hard medium produces huge vibration only at the junction of the hard–soft media, and there is no “nest effect.”