School of Resource and Safety Engineering,China University of Mining and Technology (Beijing),Beijing　 100083,China

为掌握近距离下煤层损伤基本顶的破断、失稳规律,首先对下煤层基本顶的损伤类型进行了分类,提出了基本顶损伤量化的方法,之后采用理论分析对损伤基本顶的断裂长度进行了研究,并基于"砌体梁"的"S-R"理论研究了损伤基本顶的失稳规律。研究结果表明:1损伤造成基本顶提前断裂,断裂长度随损伤量的增大而减小,达到极限损伤量时基本顶随采随垮;2损伤基本顶更易发生"砌体梁"滑落失稳,损伤量越大滑落失稳的几率越大,铰接岩块挤压力的减小是造成上述现象的原因;3"砌体梁"铰接岩块挤压力的递减速度大于铰接面抗压强度递减速度,损伤基本顶反而不易发生"砌体梁"的回转失稳;4通过对晋华宫矿307盘区11号煤层8707工作面的矿压观测,验证了损伤基本顶断裂及失稳规律。

In order to understand the broken and instability laws of damage main roof in close distance hypogynous coal seams,the damage types of main roof in hypogynous coal seams were classified and the quantitative method of main roof’s damage was also put forward,then the breaking length of the damage main roof and the laws of the damage main roof’s instability based on the “S-R” theory of the “voussoir beam” were analyzed theoretically. The research shows that:① The damage causes the main roof’s break in advance and the breaking length decreases with damage increa- ses,the main roof breaks immediately following the coal seam excavation when the damage reaches a limit;② Sliding instability of the damage main roof occurs more easily,the more damage,the more sliding instability,and the decrease of hinged rock blocks’ extrusion force is the reason for the above phenomenon;③ The declining rate of hinged rock blocks’ extrusion force is faster than that of hinged surface’s compressive strength,and the damage main roof’s rotary instability occurs difficultly on the contrary;④ The laws of the damage main roof was proved according to the mineral pressure observation at No. 8707 working face of No. 11 coal seam in No. 307 panel of Jinhuagong Coal Mine.

国家自然科学基金资助项目(51234005,51504259)；中央高校基本科研业务费专项资金资助项目(2011YZ02)；

He Shangsen,Xie Shengrong,Song Baohua,et al. Breaking laws and stability analysis of damage main roof in close distance hypogynous seams[J]. Journal of China Coal Society,2016,41(10):2596-2605.