摘要
断层破碎带是隧道施工中常见的不良地质体之一,容易导致隧道围岩失稳甚至塌方等问题。为了分析其对隧道围岩稳定性的影响规律,依托港珠澳大桥连接线南湾隧道,利用离散元软件PFC2D建立二维分析模型。结果表明:断层破碎带作用下隧道围岩应力呈非对称性,当断层位于受拉一侧时,断层对隧道水平位移的影响更为明显;当断层穿越隧道轮廓面时,断层对隧道围岩竖直方向位移的影响比水平方向位移更加显著;对比断层比邻与穿越隧道两种情况,断层与隧道相交时的最大潜在松动破坏区是未相交时的2倍以上;现场监测结果表明,当断层与隧道边墙位置相交时,该断面的位移最大且相比其他断面位移值明显增大,约为其他断面相同位置位移的2.5倍,这与数值计算中断层破碎带对潜在松动破坏区的影响规律类似。
The fault fracture zone is one of the common harmful geological bodies in tunnel construction for causing instability or collapse of the tunnel surrounding rock. To analyze its influence on the stability of the tunnel surrounding rock of the Nan-wan Tunnel of the connecting line of the Hong Kong-Zhuhai-Macao Bridge, a two-dimensional analysis model was established using the discrete element software PFC2 D. The results show that the stress of the tunnel surrounding rock is asymmetric under the action of the fault fracture zone. The tension side of the fault show a more obvious effect on the horizontal displacement of the tunnel. When fault go cross the tunnel, the vertical displacement of the surrounding rock is larger than that of the horizontal. Comparing the above two situations, the maximum potential loosening zone when fault go cross tunnel is more than twice that when it do not. On-site monitoring results show that when fault cut through the tunnel side wall, the displacement at this location is the largest and much greater than that of other sections, which is about 2.5 times the displacement at the same location of other sections. The results of the numerical calculation show similar results.
作者
黄锋
董广法
李天勇
高啸也
彭焱森
HUANG Feng;DONG Guang-fa;LI Tian-yong;GAO Xiao-ye;PENG Yan-sen(Civil Engineering College,Chongqing Jiaotong University,Chongqing 400074,China;State Key Laboratory of Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Guangdong Nanyue Transportation Investment and Construction Co.,Ltd.,Guangzhou 510150,China)
出处
《科学技术与工程》
北大核心
2020年第18期7429-7440,共12页
Science Technology and Engineering
基金
国家自然科学基金(51308574)
重庆市社会民生科技创新专项(cstc2016shmszx30009)
重庆高校创新团队建设计划(CXTDX201601024)
国家重点研发计划(2016YFC0802201)
山区桥梁及隧道工程国家重点实验室开放基金(SKLBT-19-006)。
关键词
断层破碎带
离散元
松动破坏区
围岩稳定性
fault fracture zone
discrete element
loose damage zone
stability of surrounding rock
作者简介
第一作者:黄锋(1982-),男,汉族,重庆人,博士,副教授。研究方向:隧道及地下工程。E-mail:huangfeng216@126.com。
