在两巷道的交叉段两支承压力区和顶板卸载区会发生相互叠加,因此,相对于巷道其他部位来说交叉段的围岩扰动范围会扩大,且导致变形加剧和原有支撑应力增加等不利于巷道稳定的情形出现。为分析地下采场巷道交叉段的稳定性,利用有限元数值模拟软件并考虑岩土体的应变软化特性,对5种具有代表性的交叉情形进行了数值模拟研究。研究结果表明:由于巷道交叉使得交叉几何中心附近的围岩变形进一步增加,不同的交叉角度对巷道交叉段的变形存在不同程度的影响,交叉角度越小,主巷(巷道1)锐角侧的变形越大,而且由于交叉角度的不同也使得交叉段主巷的顶板最大沉降区向锐角侧呈不同程度的偏移,交叉角度越小,偏移越为明显。从结果可以得出巷道2的变形同样也受到交叉角度的影响,从距离交叉中心4远的地方开始,交叉角度越小,巷道2的变形越大。研究成果可以为类似条件下的巷道设计和支护提供借鉴与参考。
Abutment pressure zone and roof unloading area in the roadway intersection are superimposed. Therefore, in the roadway intersection, perturbation range of the surrounding rock is greater than other parts, which leads to intensified deformation and increased original support stress, is not conducive to the stability of the roadway. In order to analyze the stability of roadway intersection, finite element simulation software is used to simulate the five kinds of typical examples and analyze the deformation of the roadway intersection. At the same time, because most of the geomaterials have the strain-softening characteristics, the rock mass characteristics of strain softening are taken into account. The result shows that: in the roadway intersection, due to the abutment pressure superimposed, the surrounding rock deformation of the roadway is further increased. For the roadway intersection, different crossover angles influence the deformation of roadway intersection differently. The specific performances are for the main roadway (roadwayl), the smaller the cross-angle is, the greater the deformation degree of acute angle side is; the bigger the cross-angle is, the greater the deformation degree of obtuse angle side is. Because the cross angles of these five model are different, the largest roof settlement areas of the main roadway (roadway 1) show different degrees of offset to the acute angle side, and the smaller the cross-angle is, the more obvious offset phenomenon is. The results also show that: the deformation of support lane (roadway 2) is also affected by cross-angle. The smaller the cross-angle is, the greater the deformation of the roadway is. The results can provide reasonable references to design and support for similar engineering.