一、平巷围岩的变形与破坏(一)非弹性变形区的出现巷道围岩的周边应力值小于岩体的强度极限(脆性岩石)或屈伏极限(塑性岩石)时,围岩周边只会产生不大的弹性位移,巷道围岩稳定。这时,从原则上讲,是不需要什么支架来维护的,如许多金属矿山的巷道中没有支架,实际上是稳定的围岩起到了支架的作用。如果应力超过了强度极限或屈伏极限,周边岩 First, the deformation and destruction of the surrounding rock (a) the emergence of inelastic deformation zone Surrounding rock roadway surrounding stress is less than the rock mass strength limit (brittle rock) or yield limit (plastic rock), the surrounding rock only Produce little elastic displacement, roadway rock stability. At this time, in principle, it does not need any support to maintain, such as many metal mines in the tunnel without stents, in fact, the stability of the surrounding rock has played a role in the stent. If the stress exceeds the strength limit or yield limit, the surrounding rock