软岩巷道在周边爆破反复作用下的损伤疲劳破坏  

THE FATIGUE DAMAGE AND BREAKING OF ROCK AFFECTED REPEATEDLY BY BLASTING STRESS WAVE

作　　者：马建军[1] 

机构地区：[1]武汉科技大学,武汉430081

出　　处：《中国矿业》2005年第11期67-69,共3页China Mining Magazine

摘　　要：本文分析了软岩巷道围岩在远区爆破弱应力波反复作用下的损伤疲劳破坏机理,认为:岩石在周期性荷载作用下会产生疲劳损伤,所引起的力学性能变化对岩体工程的长期稳定性有重要影响;岩石的疲劳破坏存在门槛值,只有在局部应变或损伤疲劳累积达到疲劳裂纹扩展门槛时,疲劳裂纹才会形成和扩展;岩石疲劳裂纹的起裂韧度比其断裂韧度小得多,因此岩石会在远低于其断裂韧度的循环应力作用下发生疲劳损伤破坏。In the paper, the fatigue damage and breaking mechanism in wall rock in soft rock tunnel affected repeatedly by weaken blasting stress wave at distant place is firstly analyzed, then, the following conclusions that the change of mechanics capability of rock caused by fatigue damage that is produced by periodical load will play a important effect on long-term stability of rock engineering; there is a threshold of change for fatigue damage of rock, and, only when local strain of fatigue damage cumulates and achieves the above-mentioned threshold, the fatigue crack will come into being and expend; at the same time, because raising breaking toughness is less that breaking toughness for fatigue crack of rock, so, fatigue damage and breaking of rock affected by cycle stress that is less than break toughness will be caused are drawn.

关 键 词：爆破应力波 远区作用 岩石疲劳损伤 起裂与断裂韧度 双K断裂准则 

分 类 号：TD235.1[矿业工程—矿井建设]