基于正交试验的底板破坏深度主控因素敏感性分析

为了研究底板破坏深度的影响因素,考虑工作面倾斜长度、采厚、采深、不同底板岩层力学参数和承压水水压,采用FLAC3D软件模拟底板破坏深度,运用正交试验法对模拟结果分析,研究影响底板破坏深度主控因素敏感性。研究结果表明,工作面斜长、采深、采厚对底板破坏深度的敏感性主次顺序为工作面斜长采深采厚;抗拉强度对底板拉破坏深度的影响为高度显著;底板岩层黏聚力、内摩擦角对底板破坏深度及拉破坏深度的敏感性不显著;抗拉强度、内摩擦角对剪破坏深度的敏感性较弱,黏聚力对底板剪破坏深度具有显著性影响;随着承压水压力的增加,底板中水平最小主应力与承压水压力越来越接近,且水平应力值接近水压的岩层范围增大,导致突水的危险性增加。

Sensitivity analysis of controlling factors on failure depth of floor based on orthogonal experiment

In order to study the influencing factors on the failure depth of floor，with the consideration of the inclined length of working face，mining thickness，mining depth，rock mechanical parameters and different water pressure，the FLAC3D was used to simulate the failure depth，and the orthogonal experiment method was used to analyze the simulation results in this study.In addition，the sensitivity of influencing factors was investigated.The results show that the sensitivity sequence of influencing factors is as follows:the inclined length of working face，mining depth，and mining thickness.Tensile strength has a significant influence on the depth of tensile failure，while the sensitivity of cohesive force and internal friction angle have no significant effect on the failure depth and the tensile failure depth.The effect of the sensitivity of tensile strength，internal friction angle on the shear failure depth is weak.The cohesive force has a significant influence on the shear failure depth.With the increase of confined water pressure，the minimum principal horizontal stress is very close to the confined water pressure，and has an increased scope，which show the risk of water inrush increases.