地下工程喷射混凝土爆破振动安全标准研究

根据一维波动理论,通过分析应力波在不同介质中反射和透射的过程,研究了爆破振动应力波对巷道围岩和喷射混凝土的破坏作用。结果表明,在爆破振动应力波的作用下,对于坚硬岩体,支护结构的破坏主要由喷射混凝土的抗拉强度所决定;而对于软岩体,支护结构的破坏则主要由喷射混凝土与围岩的交界面的抗拉强度所决定。同时,通过研究爆破振动在围岩中的传播规律,得到了掘进爆破工程中喷射混凝土支护的安全距离,为地下掘进爆破工程施工以及喷射混凝土初期支护的设计提供了一定参考。

STUDY ON BLASTING VIBRATION SAFETY STANDARDS OF SHOTCRETE IN UNDERGROUND ENGINEERING

Based on one-dimensional wave theory,the destructive effects of blasting vibration stress-wave on surrounding rock of roadway and shotcrete were studied by analyzing the process of reflection and transmission in different media.The result showed that tensile strength of shotcrete was the main factor for the damage of supporting structure for solid rock,and the tensile strength of interface between shotcrete and rock was the main factor for the damage of supporting structure for soft rock under the action of stress waves of blasting vibration.The allowable blasting vibration critical velocity under different levels of rock and different ages of shotcrete was obtained.Meanwhile,safe distance of shotcrete supporting in blasting excavation engineering was concluded by studying propagation rule of blasting vibration in the surrounding rock.These results could provide a reference for underground excavation blasting construction and design of shotcrete primary support.