动力扰动作用下充填体的力学响应研究

稳定的充填体是二步骤矿房回采的安全保障。在采矿动力作用下实现充填体的稳定性预测，是二步开采的安全控制关键。为了研究不同扰动幅值下充填体的动力响应规律，以某矿山工程为研究对象，采用Midas/GTS与FLAC3D数值模拟技术，建立了充填体动力稳定性分析的三维数值模型并进行了数值模拟分析。研究结果表明:动力扰动作用下，充填体暴露面的破坏区域由四周逐渐向中心扩展，并随着动力扰动幅值的增加，充填体暴露面破坏区域逐渐增大直至贯通破坏；充填体暴露面质点峰值振动速度随着动力扰动峰值的增加而增加，并得出了适用于该矿充填体暴露面振动峰值速度与动力扰动幅值之间的函数关系。距动力加载面越远，充填体内部质点峰值振动速度越小，且距动力加载面0~12 m处，质点峰值振动速度衰减较慢，从12~20 m质点峰值振动速度下降趋势最为明显。

Study on mechanical response of backfill under dynamic disturbance

The steady backfill is the safety assurance of the second step stope mining, and realizing the stability prediction of backfill under dynamic disturbance is the key of safety control on the second step mining. In order to obtain the dynamic response regularity of backfill under different disturbance amplitude, a three-dimensional numerical model on the dynamic stability analysis of backfill was established by using Midas/GTS and FLAC3D, and the numerical simulation analysis was carried out. The results showed that under the influence of dynamic disturbance, the destruction area of backfill exposed surface expands from surrounding to the centre gradually, and with the increase of dynamic disturbance amplitude, it increases gradually until the through destruction. The peak particle vibration velocity of backfill exposed surface increases with the increasing peak value of dynamic disturbance, and the applicable function relationship between the peak particle vibration velocity of backfill exposed surfaces and dynamic disturbance amplitude was obtained for the mine. The farther away from dynamic loading surface, the smaller the peak particle vibration velocity in backfill, and when the distance between the particle and dynamic loading surface is 0~12 m, the attenuation of peak particle vibration velocity is slower, while the distance is 12~20 m, the downward trend of peak particle vibration velocity is the most obvious.