岩层倾角对巷道结构稳定性的影响

Effect characteristics of rock strata with varying inclinations on stability of roadway structure

为了解决倾斜岩层巷道存在的变形不对称问题,建立了巷道两帮围岩受力力学模型.分析表明,巷道高帮围岩受到沿岩层倾向向下的"拉力"和岩层法向上的压力作用,围岩容易发生拉破坏;巷道低帮围岩受沿岩层法向和岩层倾向压力作用,围岩相对稳定.利用UDEC软件对不同倾角模型模拟分析发现倾斜岩层巷道结构非均称变形表现为3个方面:(1)巷道高帮变形量大于低帮变形量;(2)岩层倾角增加,高低帮水平变形量都增加,高帮水平变形量增加速度大于低帮增加速度,岩层倾角增加,高低帮垂直变形量先增加再逐渐减小;(3)高帮垂直位移量在帮角处最大,随高度增加而减小,低帮垂直位移量在底角处最小,随高度增加而增加.

Aiming at the roadway asymmetric deformation within inclined rock strata,the mechanics model of roadway sidewalls is built.The analysis shows that the surrounding rock tensile failure of long side is likely to occur under downward tension of inclined rock strata and strata normal direction stress,whereas the surrounding rock of short side is relatively stable under strata normal direction and inclined rock strata stress.According to the numerical simulation analysis of different dip angles by UDEC（Universal Distinct Element Code）,it is found that the structure asymmetric deformation of the inclined rock strata roadway has three characteristics as follows：（1）the high side deformation degree is greater than that of low side within roadway;（2）the dip angles of rock strata increases,it naturally follows the sidewalls horizontal deformation degree and the increase of high side horizontal deformation degree is faster than that of low side,while the sidewalls vertical deformation degree increases at first and gradually decreases when the dip angles of rock strata increases;（3 ）the high side vertical displacement presents the greatest degree at the base angle and decreases with the height increases,while the low side vertical displacement presents the slightest degree at the base angle and increases with the height increase.