直墙半圆拱巷道爆破震动数值分析

为利于判断巷道围岩在爆破荷载作用下的稳定性及巷道内壁混凝土衬砌的安全，采用ANSYS/LS-DYNA分析了巷道钻爆法掘进爆破荷载作用下震动区岩体的动力响应。结果表明，近区岩体内部爆破压力、单元有效应力、质点振动速度随爆心距的衰减规律基本符合萨道夫斯基经验公式，单元有效应力与质点振动速度的衰减规律具有很强的相关性；巷道围岩临空面上的质点振动速度以沿巷道方向的振动速度为主，巷道横截面内垂直临空面方向次之，横截面内沿临空面方向为最小。巷道同一横截面处各质点的振动波形基本相同，拱顶的振动速度峰值比帮部的要大10%左右，拱与帮的连接处振动速度峰值较小。巷道围岩沿巷道方向临空面上质点振动速度衰减规律也基本符合萨道夫斯基公式，以上分析结果对采用钻爆法进行岩巷施工时，控制近区震动区爆破荷载对结构的影响具有一定的指导作用。

Blasting vibration numerical analysis of vertical wall semicircular arch roadway

In order to determine the stability of surrounding rock or the safety of concrete lining under blasting load, this paper adopted ANSYS/LS-DYNA software to analyze the dynamic response of rock mass under blasting vibration load when rock tunnel excavation with drilling and blasting methods . The results show that the attenuation law of blasting pressure，element effective stress and particle vibration velocity can be expressed by Sadaovsky empirical formula approximately, the attenuation law of particle vibration velocity and element effective stress have well relationship. Particle vibration velocity on the surface of surrounding rock is mainly along the axis of tunnel, and which is less along the normal line, and the least is on the surface. All particles on the same cross section have the same vibration wave shapes. The maximum particle vibration velocity on the arc is larger by 10% than on the wall slope, and that of conjunction is the least. The maximum particle vibration velocity of all nodes along the axis of tunnel attenuates according to Sadaovsky empirical formula. All the results are helpful to analyze the influence of blasting vibration field when excavating tunnel with drilling and blasting methods.