交错巷道巷间围岩承载结构稳定性分析

针对普遍存在的矿井交错巷道围岩体稳定性及支护问题,运用极限平衡分析和弹塑性力学建立交错巷道巷间围岩稳定性分析判别方程,探讨了交错巷道巷间围岩稳定性主要影响因素,并进行了工业性试验。结果表明:交错巷道巷间围岩体受围岩水平应力集中叠加影响,围岩破坏自巷间围岩体上下表面向中部延伸,加之巷间围岩体尺寸有限,一旦破坏贯通将致使巷间围岩承载存在失稳隐患;交错巷道巷间距越小,越近乎平行布置都会加剧巷间围岩破坏且诱发巷间围岩破坏贯通,合理设计断面尺寸及下方巷道合理支护强度可有效控制并维持围岩稳定;现场采用交错巷道联合支护方案后,交错位置上巷道断面完整无较明显变形且下巷道围岩最大变形量小于100 mm,支护效果显著。

Stability analysis on bearing structure in the surrounding rock between staggered roadways

To overcome the common problems of surrounding rock stability and supporting in staggered roadways,the stability discriminant equation on the surrounding rock between staggered roadways was established by the limit equilibrium analysis and the elastic-plastic mechanics.Also,the main influencing factors on the surrounding rock stability in staggered roadways were discussed,and the industrial experiment was conducted.The result shows that the surrounding rock body between staggered roadways is affected by the superposition of the horizontal stress concentration.The failure of the surrounding rock between staggered roadways extends from the upper and lower surfaces of surrounding rock body to the deep rock strata,coupled with the finite size of the surrounding rock between staggered roadways.The fracture coalescence of the surrounding rock between staggered roadways could lead to a potential instability of the staggered roadways.The small distance between staggered roadways and the almost parallel staggered-roadways arrangement can aggravate the failure of roadway surrounding rock and induce the fracture coalescence of the surrounding rock between staggered roadways.The reasonable section size and supporting strength of roadway could effectively control and maintain the stability of staggered roadways.After adopting the combined support scheme of staggered roadways in the field,the sections of staggered roadways are intact and have no obvious deformation,and the maximum deformation of surrounding rock next to the lower staggered roadway is less than 100 mm,and the supporting effect on staggered roadways is obvious.