摘要
高强度采动影响下,煤壁片帮问题在大采高工作面日趋突出,针对断层构造处高帮煤壁稳定性恶化且难以支护的问题,采用数值模拟、理论分析、室内及现场试验等综合研究方法,分析了断层构造处大采高工作面煤壁破坏机理、稳定性影响因素及控制措施。断层构造处工作面前方煤体塑性破坏区的扩大增加了揭露前煤体损伤程度,为片帮事故发生奠定了基础;建立高帮煤壁稳定性分析力学模型,分别得到剪切、拉裂型片帮发生判据;得到煤体破坏起裂角βsm,βtm(非恒值)确定公式及影响因素;煤体黏聚力、内摩擦角及采高对两种片帮形式的影响程度均为:黏聚力>采高>内摩擦角;断层构造处片帮事故发生频率、危害程度急剧增大原因为:采高过大、煤体物理力学性能降低、顶板载荷增大;最后以王庄8101工作面过F286断层为工程背景,提出了重型设备"低割煤高度、高初撑力、高护帮高度"结合煤壁注浆的综合过断层措施,有效改善了煤壁控制效果,提高了开机率。
Rib falling becomes a main problem at mining face with large cutting height under high-intensive extraction and even leads to the stop of a mining operation. Numerical simulation,theoretical analysis,laboratory test and in-situ monitoring were carried out for improving the stability of coal wall as working face approaching fault and the mechanism of rib falling. Also,the influential factors and their control technologies were analyzed. Expansion of plastic area magnified the damage degree of coal before its exposure to fault,which might cause accident. Mechanical model for stability analysis was built,and the criterion of shear and tensile rib falling were put forward respectively.Formula used for calculating crack angle was deduced for the first time,then its influential factors were analyzed.The impacting extent to shear and tensile rib falling of different factors were cohesion >mining height >friction. The frequency and hazard degree of rib fall increase near the fault because of its large mining height,the deduction of coal physical and mechanical properties and the increase of roof load. In the study,the controlling measures of'small cutting height,high setting force,large coal wall protection height'with heavy equipments and grouting were applied at 8101 mining face in Wangzhuang Coal Mine and the in-situ measurement showed a good effect.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2015年第1期42-49,共8页
Journal of China Coal Society
基金
国家重点基础研究发展计划(973)资助项目(2013CB227903)
关键词
断层
煤壁片帮
大采高
煤体参数
注浆
fault
rib spalling
large mining height
coal parameters
grouting
