边帮压煤在不同回采条件下边坡变形破坏及稳定性分析

Analysis of deformation failure and stability of slope coal under different mining conditions

因边坡存在典型失稳特性,边帮煤回采会进一步加剧边坡发生变形和失稳现象;采用FLAC3D构造边坡结构模型对边帮煤在不同回采状况下边坡变形破坏及稳定性进行分析预判。结果表明:不同回采条件,边坡内部岩体塑性区扩展形态和范围不同,对边坡平盘所形成的扰动破坏也不相同;逆坡和顺坡回采相比,在回采长度及边坡稳定性方面都比顺坡回采差,顺坡回采在一定程度上可以保证边坡的稳定性,虽存在局部滑移现象,但整体稳定性较好,逆坡回采边坡存在失稳现象;上煤层回采边坡存在局部失稳现象,整体稳定性较好,下煤层回采塑性区远离边坡平盘,稳定性比上煤层回采更优;由此可以得出边坡稳定性和回采深度有关,回采深度越大边坡稳定性越好。

Due to the typical instability characteristics of the slope, slope coal mining will further aggravate the deformation and instability of the slope. Therefore, we use FLAC3Dslope structure model to analyze and predict the deformation, failure and stability of the slope coal under different mining conditions. The result shows that the expansion form and range of the plastic zone of the rock mass inside the slope are different different mining conditions, and the disturbance and damage to the slope flat plate are also different;compared with the downhill stoping, the uphill stoping is worse than the downhill stoping in terms of length and slope stability;the downhill stoping can ensure the stability of the slope to a certain extent;although there is a local slip phenomenon, the overall stability is better, and the instability phenomenon exists in the reverse slope mining slope;the upper coal seam mining slope has local instability, and the overall stability is good. The lower coal seam plastic zone is far away from the slope flat plate, and its stability is better than that of the upper coal seam. It can be concluded that the slope stability is related to the mining depth. The greater the mining depth, the better the slope stability.