沿空留巷巷旁支护体作用机制及工程应用

Mechanisms of roadside support in gob-side entry retaining and its application

巷旁支护体稳定是沿空留巷成功的关键。通过建立沿空留巷上覆岩层结构力学模型,分析了巷旁支护体在3个阶段的受力和变形特征,得到了巷旁支护体的作用机制,即巷旁支护体设置后快速增阻,即时支撑巷内顶板,工作面后方周期来压前达到切顶阻力切落采空区一定高度的顶板,上覆岩层剧烈活动稳定前有较大的变形能力及稳定后有较高的后期强度。在上述研究的基础上,以九里山矿24021工作面沿空留巷为工程背景,在巷内支护和巷旁充填材料确定的情况下,采用数值模拟方法分析了不同巷旁支护体宽度时的沿空留巷维护效果,确定了合理的巷旁支护体宽度。该研究成果成功应用于工程实践。

The stability control of roadside support body is the key to keep gob-side entry retaining stable.According to the structural mechanics model of gob-side entry retaining overlying strata,the paper analyzes the load and deformation characteristics of roadside support in the three stages and obtains supporting mechanism of roadside support as follows.Roadside support body could support the roof instantly by increasing support resistance in the setting stage,meets the requirement of cutting off a certain height of the roof before a periodic abutment loading at the back of working face,and has a large deformation capacity during overlying strata movement and a high post-strength after stability of overlying strata movement.Based on the above investigations and the geological conditions of panel 24021 in Jiulishan colliery,we analyze the effect of support body width on the performance of a gob-side entry retaining,and determine a rational width of support body in the condition of support parameters and filling materials.Research results are successfully applied to a field practice.