矿震扰动下立体采空区群动力响应研究

The Study of the Stereoscopic Goaf Group Dynamic Response with Mining Tremor Disturbance

以某金属矿山8号矿体1 100~1 250 m中段36~42勘探线的复杂立体采空区群为工程背景,基于动力学理论,提出了矿震扰动下立体采空区群的动力响应模型,揭示了采空区群在矿震扰动下的动力响应规律。考虑到围岩剪切作用,引入剪切力作用修正因子矩阵λ和作用系数矩阵B表征围岩的剪切力。根据动力响应模型建立对应的类动力响应方程,采用Newmark-β法对微分方程进行迭代求解。结果表明:该方法可直观地反映矿震扰动下立体采空区群的动力响应规律,与数值模拟得到的位移、速度时程曲线变化趋势一致;岩体位移极值最大的部位是承载垮落物的顶板岩体;采用Newmark-β法提高了理论计算的效率;动力响应模型法较好地拟合了数值模拟结果,验证了该法的可行性,进而为采空区群矿震防治提供理论指导。

Taking the stereoscopic goaf group of the 36~42 exploration line in the 1 100~1 250 m middle section of No. 8 orebody in a metal mine as the engineering background,based on the dynamics theory,a dynamic response model of the stereoscopic goaf group with the disturbance of mining tremor is proposed,and the dynamic response rule of the goaf group with the disturbance of mining tremor is revealed. Considering the shear effect of surrounding rock,the shear force matrix λ lambda and the action coefficient matrix B are introduced to characterize the shear force of the surrounding rock. According to the dynamic response model,the corresponding similar dynamic response equation of the class is established,and the Newmark-βmethod is applied to work out the solution of the equation iteratively. The results show that this method can intuitively reflect the dynamic response law of the stereoscopic goaf group with the disturbance of mining tremor,which is consistent with the changed trend of displacement and velocity time history curve obtained by numerical simulation. The maximum position of the rock mass displacement is the roof rock which carries the collapsed object,and the Newmark-β method is used to improve the efficiency of the theoretical calculation. The dynamic response model method fit the numerical simulation results well,verify the feasibility of the method,and then provide theoretical guidance for the prevention and control of mining tremor in the goafs.