摘要
为分析多节理顶板失稳过程及应力重新分布规律,采用离散元软件3DEC建立了工作面回采模型,模拟分析了工作面回采过程中多节理顶底板的失稳机理及支承压力、节理法向应力的分布规律。模拟结果表明:多节理顶板的失稳是块体三铰拱结构沿节理面破坏导致的;由于横向挤压力的存在,只有铰点处的节理面才会发生开裂;多节理底板较完整岩体而言,底鼓现象更加明显;顶板发生初次跨落之前,最大支承压力出现位置随工作面推进而距工作面越来越远,最大、最小节理法向应力相对工作面位置基本相同;节理面正应力反映了块体间的相互挤压程度,数值上大于支承压力。
In order to analyze the process of multi-joint roof failure and stress redistribution,the mining face model is established by 3DEC,the instability mechanism and the distribution law of the bearing pressure and the joint normal stress are analyzed and simulated in the mining process.The simulation results show that：the failure of the multi-joint roof is caused by the failure of the block three-hinged arch structure along the joint surface;due to the presence of lateral squeezing force,only the hinge at the joints will be cracking;comparing with the more complete rock,the heaving phenomenon of multi-joint floor is more obvious;before the first occurrence of the roof,the appearance of the maximum bearing pressure is farther and farther from the working face with the advancing of the working face,the maximum and minimum joint normal stress is basically the same relative to the distance of working face;the normal stress of the joint surface reflects the degree of mutual squeezing between the blocks,which is greater than the bearing pressure.
作者
董鹂宁
DONG Lining(College of Architecture and Civil Engineering, Xi＇ an University of Science and Technology, Xi＇ an 710054, China)
出处
《煤矿安全》
北大核心
2017年第12期187-190,194,共5页
Safety in Coal Mines
基金
西安科技大学培育基金资助项目(2009005)
