大埋深高地压弱结构面顶板岩层诱发冲击地压离心模型试验

Centrifuge model tests on rock brusting induced by great depth highly stressed roof strata of weak structural plane

针对赵楼矿井首采区近1 km深部拟开采的3煤(即山西组稳定可采煤层)冲击地压问题,考虑断层切割顶板的实际情况,概化出弱结构面顶板工程地质模型并进行离心模型试验。研究结果表明:对于离心模型模拟的弱结构面顶板条件,直接顶来压过程中煤柱压力较低,而老顶来压过程对煤柱受力的影响明显,是引起冲击地压的主要动力来源;顶板被断层切割时,顶板岩层的完整性受到破坏,应力在构造部位重新分布,形成构造应力集中,是引发冲击地压的危险部位;回采工作面揭露断层后,下盘顶板沿断层面失去煤体支撑而形成"悬臂梁",由此大大降低了顶板的支撑强度,容易发生因顶板突然断裂而形成的冲击压力,这种构造条件下厚-巨厚层极坚硬顶板易发生冲击地压。研究结果为赵楼矿井巷道的合理布置、支护及采动冲击地压的潜势性评价提供了重要的参考依据。

For the problem of rock busting of three coals intended to be exploited nearly 1 km depth of Zhaolou Mine,considering the actual situation of the fault cutting roof,the geological model of weak structural plane was built and centrifuge model tests were conducted.The results show that the direct roof weighting process has comparatively low pressure on coal pillar,whereas the main roof weighting process has more significant influence on it,which is the primary power origin of rock bursting.In the context where the roof is cut by faults,the integrity of roof strata is damaged,stress redistributes at construction site,tectonic stress concentration is formed which is dangerous position inducing rock brusting.Footwall roof loses support from coal body and then transforms into cantilever beam after the extracting working face exposes the faults,thus the support intensity of the roof greatly reduces,and it is prone to occur rock brusting produced by sudden rupturing roof.Thick to hugely thick roof and extremely hard roof are easy to form rock brusting in this structure.The research provides an important reference for rational arrangement,reinforcement and mining rock brusting of roadway of Zhaolou Mine.