摘要
针对断层区煤巷顶板破断问题,分别建立了正断层和逆断层构造区的顶板弹性深梁力学模型,研究了顶板应力分布规律,并以Mohr-Coulomb破坏准则为判据,分析了不同顶板压力、支护强度、跨高比等因素下的顶板破断机制。理论分析表明,顶板深梁最大有效剪应力随跨高比增大而增大;其随跨高比不同而呈现出3种不同破断模式;穿越断层的巷道在断层区域应尽早使用强力支护系统,提高支护强度;穿越正断层的巷道在断层面附近应当提高护表效果。根据理论分析结论提出,在煤巷断层区使用让压型锚索箱梁支护系统,可对顶板围岩进行及时强力支护,实现"先控后让再抗",既能有效发挥支护系统作用,又能充分发挥围岩自承能力。上述支护对策应用于巨野矿区断层区煤巷支护方案设计中,有效防止了顶板事故的发生,验证了理论分析的正确性。
Based on the issues of roof collapse in fault zones,roof elastic thick outrigger mechanical models in normal fault zone and reverse fault zone are established;the roof stress distribution law is researched;and the roof collapse mechanisms under different roof pressures,different support strengths,different span-depth ratios,etc.are analyzed according to the Mohr-Coulomb failure criterion.Theoretical analysis shows that the maximum effective shear stress of roof thick outrigger increases with the growth of span-depth ratio;and it presents three different kinds of fracture modes with the increasing of span-depth ratio;support strength should be enhanced in the roadway crossed faults;surface protection effect should be enhanced near normal fault plane.According to the theoretical analysis,pressure relief anchor box beam support system is put forward to apply to fault zones,by which roof is supported opportunely and forcefully;and the effect of first anti-pressure,then pressure relief,at last anti-pressure is implemented;and the support system works effectively;the self-bearing ability of surrounding rock is put into full play.The mechanism research conclusion is applied to the support scheme in similar fault zones of the mine;and it prevents roof collapse accidents effectively,so as to prove that the conclusion of theoretical analysis is correct.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2012年第10期3093-3102,共10页
Rock and Soil Mechanics
基金
国家自然科学基金青年科学基金资助项目(No.51209127)
教育部博士点基金(No.20110131110030)
山东省自然科学基金面上项目(No.ZR2009FM009)
关键词
煤巷
断层区
顶板
破断机制
力学模型
箱型支护梁
coal roadway
fault zone
roof
fracture mechanism
mechanical model
box supporting beam
