非等压应力场巷道围岩主应力差分布规律与稳定性分析  

Distribution law of principal stress difference and stability of roadway surrounding rock in unequal stress field

作　　者：赵洪宝[1] 程辉[1] 刘绍强 秦逢缘 王伊阔 ZHAO Hongbao;CHENG Hui;LIU Shaoqiang;QIN Fengyuan;WANG Yikuo(School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《采矿与安全工程学报》2021年第6期1111-1121,共11页Journal of Mining & Safety Engineering

基　　金：越崎杰出学者计划项目(800015Z1179);河北省生态智慧矿山联合基金项目(E2020402036);中央高校基本科研业务费研究生科研创新能力提升项目(2020YJSNY07)。

摘　　要：采用理论分析、数值模拟方法对非等压应力场巷道围岩主应力差分布规律与稳定性进行研究,重点分析不同侧压系数下巷道顶底板与两帮的主应力差分布演化规律、塑性区形态和变形演化规律。研究结果表明:侧压系数λ<1时,巷道两帮破坏范围大于顶底板;λ>1时,顶底板破坏范围大于两帮。基于数学拟合得到巷道围岩最大主应力差轨迹线方程,该式可计算出围岩破坏最严重区域。巷道在围岩四周会形成主应力差承载壳,λ增大过程中,承载壳形态演化过程为:水平的类"8"字形→扁平椭圆形→圆形→瘦高椭圆形→类"8"字形。顶底板主应力差峰值随着λ的增大而增大,并向围岩深部转移,两帮峰值随着λ的增大而减小,向围岩浅部转移。巷道围岩塑性区总是分布在主应力差承载壳内,其形态演化过程与主应力差承载壳保持一致。λ增大过程中,巷道顶底板位移曲线离散程度不断增大,两帮位移曲线离散程度先减小后增大。λ<1时,两帮表面位移>顶底板表面位移;λ>1时,顶底板表面位移>两帮表面位移。λ越接近1,巷道围岩稳定性越好。以回坡底煤矿11-1021巷为工程背景,研究发现巷道围岩主应力差呈倾斜的类"8"字形分布,理论分析结果与巷道实际破坏情况吻合,验证了理论的正确性。Distribution law and stability of principal stress difference of roadway surrounding rock in unequal stress field were studied through theoretical analysis and numerical simulation. The evolution law of principal stress difference distribution, plastic zone shape, and evolution law of deformation in roadway roof, floor, and two sides under different lateral pressure coefficients were analyzed. The results have shown that when coefficient of lateral pressure λ<1, failure range of two sides of roadway is larger than roof and floor;when λ>1, failure range of roof and floor is larger than two sides. Based on mathematical fitting, trajectory equation of maximum principal stress difference was obtained through fitting, which can accurately calculate the area with the most serious damage of surrounding rocks. With the increase of λ, shape evolution process of principal stress difference bearing shell of roadway surrounding rock evolves from horizontal "8" shape → flat ellipse → round → thin high ellipse →similar "8" shape. With the increase of λ, peak value of principal stress difference of roof and floor increases and transfers to deep part of surrounding rocks, while that of two sides decreases and transfers to shallow part of surrounding rocks. Plastic zone of surrounding rocks is always distributed in principal stress difference bearing shell, and its shape evolution process is consistent with principal stress difference bearing shell. With the increase of λ, dispersion degree of displacement curve of roadway roof and floor increases, and that of two sides first decreases and then increases. When λ<1, surface displacement of two sides > that of roof and floor;when λ > 1, surface displacement of roof and floor >that of two sides. The closer λ is to 1, the better the stability of surrounding rock is. With roadway 11-1021 of Huipodi Coal Mine as engineering background, it was found that principal stress difference of surrounding rocks is like an oblique "8" shape. The theoretical analysis results are in

关 键 词：非等压应力场 侧压系数 主应力差 承载壳 塑性区 

分 类 号：TD322[矿业工程—矿井建设]