基于声波测试的爆破震动对巷道围岩体累积损伤分析

Using sonic testing method to study cumulative damage of surrounding rock under blasting vibration

为了研究巷道开挖过程中爆破动荷载对巷道围岩体的累积损伤,运用RSM-SY5智能型声波仪测试巷道围岩体的岩体声波速度。结合理论推导,分析多次爆破震动对巷道围岩体的累积损伤。结果表明,第一次爆破对巷道围岩体的影响最大,多次爆破震动的累积损伤作用仅增加围岩体的破碎程度,并没有扩大巷道围岩体的损伤范围。巷道围岩体的松动圈是由多次爆破累积损伤造成的,且对巷道顶板的累积损伤程度大于巷道两帮的累积损伤。根据巷道围岩体的累积损伤程度,巷道顶板围岩体的1.5 m范围内为开挖引起的围岩体破碎带,1.75~2.5 m为巷道围岩体裂隙带,2.75 m以外的岩体为开挖扰动带和原岩区。此研究为巷道开挖过程中控制巷道的稳定性和巷道支护提供可靠参考依据。

In order to study the cumulative damage of roadway surrounding rock in the process of roadway excavation,the intelligent acoustic meter of RSM-SY5 was used to measured acoustic velocity in the roadway.Combining theoretical derivation to analysis the cumulative damagecaused many times blasting vibration in the roadway surrounding rock. The results show that the first blasting vibration hasthe strongest impact onsurrounding rock of roadway. The cumulative damage of many times blasting vibration have only impact damagedegree of surrounding rock,not expand the damage scope of roadway surrounding rock. Roadway surrounding rock loose circle is caused by blasting cumulative damage for several times,and for the cumulative damage of roadway roof to a greater extent than that of two sides of roadway damage. Based on the cumulative damage degree of roadway surrounding rock mass,Surrounding rock mass of roadway roof of 1. 5 m range belong to fracture zone,the range 1. 75 m to 2. 5 m is fissure zone,and beyond 2. 75 m is excavation disturbed zone and the original rock area respectively. This study provides a reliable reference thatto control the stability and supporting of roadway in the process of roadway excavation.