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.
出处
《中国矿业》
北大核心
2005年第11期67-69,共3页
China Mining Magazine
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
Blasting Stress Wave Affect by Distant Place Fatigue Damage of Rock Raising Breaking and Breaking Toughness Double k Breaking Guide Line
