摘要
为了解结构面倾角对诱发岩爆动力失稳行为的影响,通过采用GDEM数值模拟软件,开展了含不同角度闭合多节理的直墙拱形隧道在全断面开挖卸荷作用后对诱发结构面型岩爆的数值模拟研究,分析了隧道在开挖卸荷下围岩的裂纹扩展行为、应力变化、碎块体的体积与块体的弹射速度等力学特征。研究表明,由于围岩内节理倾角空间位置的不同,导致在隧道开挖卸荷后,容易在节理尖端围岩处形成应力集中,造成不同程度的应力重分布,改变了围岩裂纹的扩展行为和承载能力。且围岩破坏模式受结构面倾角的影响明显,缓倾角强化了结构面的抗剪切作用,不易形成岩爆。陡倾角易诱发压剪滑移破坏,诱发岩爆。研究结果对含节理隧道的开挖设计与灾害防治有重要的工程意义和学术价值。
In order to understand the influence of structural plane dip Angle on the dynamic instability behavior of induced rock burst,a straight wall arch tunnel with multiple joints closed at different angles was carried out by using GDEM numerical simulation software.After full section excavation and unloading,the induced rock burst of structural plane was numerically simulated.The mechanical characteristics of surrounding rock such as crack propagation behavior,stress variation,volume and ejection velocity of the block under tunnel excavation and unloading are analyzed.The results show that the different degrees of stress concentration can be easily produced at the tip of the joint after the tunnel excavation,due to the difference in the spatial position of the structural plane.As a result,the difficulty of the crack generation in the surrounding rocks is varying,which changes the crack propagation behavior and bearing capacity of the surrounding rocks.The failure modes of the surrounding rock are obviously affected by the structural plane inclination angle.The gentle inclination angle strengthens the anti-shear behavior of the structural plane,resulting in no or slight rock burst.A steep inclination angle can easily induce rock burst due to the compression-shear slip failure of structural planes.The research results have great engineering and academic values for the excavation design and disaster prevention of the jointed tunnel.
作者
周雄
孟凡震
修占国
岳祝凤
王玮
崔广昊
王在泉
ZHOU Xiong;MENG Fanzhen;XIU Zhanguo;YUE Zhufeng;WANG Wei;CUI Guanghao;WANG Zaiquan(College of Science,Qingdao University of Technology,Qingdao,Shandong 266000,China;Colleye o Civil Enyineeriny,Qingdao University 0$Technology,Qingdao,Shandony 266000,China)
出处
《水利与建筑工程学报》
2023年第4期94-100,共7页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金面上项目(51879135,42272334)
山东省泰山学者青年专家项目,山东省青创团队(2019KJG002)。
关键词
直墙拱形隧道
岩爆
开挖卸荷
结构面倾角
连续与非连续的数值方法(CDEM)
straight wall arch tunnel
rock burst
excavation unloading
structural plane inclination
continu-um-based discrete element method(CDEM)