爆破切顶卸压合理参数模拟研究

Simulation Study on Reasonable Parameters of Blasting Top Cutting Pressure Relief

为解决厚坚硬顶板难垮难落的问题,利用数值模拟软件对某矿井爆破切顶卸压情况进行分析,发现爆破后岩体内部可以分为压碎区、破裂区和震动区三个部分。对不同切顶参数下切顶效果进行模拟分析,确定最佳切顶角度为15°,最佳卸压高度为8 m;同时对切顶前后护巷煤柱应力情况进行分析,发现切顶后煤柱应力峰值为13.60 MPa,未切顶的煤柱应力峰值为37.48 MPa,切顶后巷道围岩稳定性得到了有效的控制,为坚硬顶板治理作出了贡献。

In order to solve the problem that thick and hard roof slabs are difficult to collapse and fall,this paper uses numerical simulation software to analyze the blasting top cutting and pressure relief,and finds that the rock body can be divided into three parts after blasting,namely crushing area,fracture area and vibration area.It simulates and analyzes the effect of roof cutting under different roof cutting parameters,and determines that the optimal roof cutting angle is 15°,and the reasonable value of relief height is 8 m.At the same time,it analyzes the stress of the coal pillar before and after roof cutting,and finds that the peak stress of the coal pillar after roof cutting is 13.60 MPa,and that of the coal pillar without roof cutting is 37.48 MPa.The stability of surrounding rock of the roadway after roof cutting has been effectively controlled,making contributions to the treatment of hard roof.