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以五阳矿为工程背景,通过三轴压缩围压分级长时加载试验得到了顶板岩石的力学性质,模拟分析了有支护巷道围岩的黏弹性力学性能,提出控制煤层上山变形的围岩控制原则,并进行了支护实践。研究认为:巷道围岩变形是一个时间过程,荷载在加载一定时间后变形趋于稳定,且其变形稳定时间随加载载荷的增大而呈指数增大;在轴向应变未稳定时增加围压,可有效降低轴向应变速率,即在巷道变形未稳定期间增加围压可加速围岩变形的稳定,防止围岩失稳;顶板采用预应力锚杆、锚索支护后,虽然能有效地控制了顶板变形及塑性区的发展,但是会同时加剧煤帮和煤层底板的变形,即在对顶板进行锚杆、锚索强化支护的同时,必须强化两帮和底板的稳固;适当的应力转移有利于围岩的最终稳定,一次支护分级加载的围岩控制原则对控制厚煤层上山巷道围岩变形效果显著。
Taking the Wuyang mine as the engineering background, the mechanical properties of the roof rock are obtained by triaxial compression confining pressure grading long-term loading test. The viscoelastic mechanical properties of the surrounding rock with the supporting roadway are simulated and analyzed, and the surrounding rock Control principle, and carried out support practice. The study shows that the deformation of surrounding rock is a time course, the deformation of the roadway tends to be stable after a certain period of loading, and the deformation stability time increases exponentially with the increase of the loading load. When the axial strain is not stable, the confining pressure increases , Can effectively reduce the axial strain rate, that is, during the unstable deformation of the roadway to increase the confining pressure can accelerate the stability of surrounding rock deformation and prevent the surrounding rock instability; roof with prestressed anchor, anchor cable support, although effectively Control the deformation of the roof and the development of the plastic zone, but at the same time it aggravates the deformation of the coal gangue and the floor of the coal seam. That is to say, while strengthening the support of the roof and anchor cables, it is necessary to strengthen the stability of the two gangs and the floor. Appropriate stress The transfer is beneficial to the final stability of the surrounding rock. The principle of the surrounding rock control of the grade and loading of a retaining and supporting can significantly affect the surrounding rock deformation of the roadway in the thick seam.