论文部分内容阅读
为研究深部回采巷道围岩大变形破坏规律,在地质力学评估及矿压显现特征实测的基础上,采用真三轴相似模拟方法,模拟了不同加载梯度下巷道围岩应变特征。结果显示,在浅埋静水压力条件下,巷道围岩呈现“浅部拉应变、深部零应变”的特征;深埋静水压力及初掘采动应力下巷道围岩出现“径向应变拉压交替分布”现象;当采动应力集中系数大于2时,深埋巷道围岩应变进入非线性大应变状态。采用FLAC3D的应变软化模型与摩尔-库仑模型,对比研究了深部回采巷道围岩位移、塑性区分布规律。结果表明,应变软化条件下,巷道围岩产生拉、压分区破坏且软化后的围岩位移与实测结果更吻合。综合研究结果,揭示了深部回采巷道围岩拉、压分区的产生机制,初步提出了注浆、喷层等措施,防止过度应变软化引起深部回采巷道围岩大变形,为类似巷道稳定性控制提供了一定的参考。
In order to study the law of large deformation and failure of surrounding rock in deep mining roadway, the true triaxial similarity simulation method was used to simulate the strain characteristics of surrounding rock under different loading gradients, based on the geomechanical assessment and the characteristics of rock pressure. The results show that under the conditions of shallow hydrostatic pressure, the surrounding rock of the roadway exhibits the characteristics of “shallow tensile strain and deep zero strain”, and the "radial strain When the mining stress concentration factor is greater than 2, the surrounding rock strain of the deep roadway enters the state of nonlinear large strain. The strain softening model and the Mohr-Coulomb model of FLAC3D are used to study the displacement and plastic zone distribution of surrounding rock in deep mining roadway. The results show that under the condition of strain softening, the surrounding rock of the roadway produces tension and pressure zone failure and the softened surrounding rock displacement is more consistent with the measured results. According to the comprehensive research results, the formation mechanism of surrounding rock pull and pressure zones in deep mining roadway is revealed, and some measures such as grouting and shot blasting are preliminarily proposed to prevent over-strain softening from causing large deformation of surrounding rock in deep mining roadway and provide similar control of roadway stability A certain reference.