摘要
受交通廊道的空间限制,隧道工程逐渐出现了多洞并行的布设形式。当相邻隧道净间距较小时,建设期间可能出现相互影响,降低围岩稳定性。将该课题简化为平面应变条件下的多洞并行等间距毛洞隧道围岩稳定性问题,应用刚体平动运动单元上限法开展计算分析,获取失稳临界状态下围岩稳定系数曲线和滑移线网破坏模式的定量数据,揭示围岩稳定性与潜在破坏模式随强度参数、隧道埋深H和多洞净距S等因素间的演化规律。研究结果和已有双洞并行隧道的对比分析表明:净间距S大于转换间距Str后,二者均表现为单洞独自破坏形式,且稳定系数Ncr数值吻合较好;而净距S较小时,多洞并行隧道围岩表现为上方整体下沉条件下的中夹岩破坏,较之双洞并行情况围岩稳定性大大降低。研究结果可为多洞并行隧道围岩稳定性评价及加固方案制定等工作提供数据支撑。
The layout of parallel tunnels is adopted in many tunnel construction due to the limited space of traffic corridor.The adjacent tunnels with a small clear spacing distance may cause significant interaction to reduce the stability of the surrounding rock.The problem is simplified as the stability model for the parallel multi-line tunnels with equidistance under plane strain.The systematic analysis is carried out using the upper bound method for rigid body translational motion elements.The curves for the stability coefficient of surrounding rock of tunnels the and the failure mode of slip line network under the instable critical state are obtained.The stability of the surrounding rock and the potential failure mode varying with strength parameters,tunnel buried depth H and clear spacing distance of multi-line tunnels S are discussed.The results of the parallel multi-line tunnels are compared with those of the twin-line tunnels reported by the existing literature.It is shown that when the clear spacing distance S is greater than the conversion distance Str,the failure mode of a single tunnel is presented for the both types of tunnels,and the stability coefficient Ncr is more consistent.In contrary,when the clear spacing distance S is small,the collapse of the middle rock column caused by the settlement in the whole upper part of tunnels is presented in the surrounding rock of the parallel multi-line tunnels.The stability of the parallel multi-line tunnels greatly decreases compared with the case in the twin-line tunnels.The results may provide data support for evaluation of the stability of the surrounding rock and formulating the reinforcement scheme for the parallel multi-line tunnels.
作者
杨峰
高廉镇
高益康
阳军生
YANG Feng;GAO Lianzhen;GAO Yikang;YANG Junsheng(School of Civil Engineering,Central South University,Changsha 410075,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2023年第5期976-985,共10页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(51878669)。
关键词
多洞并行隧道
围岩稳定性
极限分析上限法
刚体平动运动单元
滑移线网
破坏模式
multi-line tunnel
surrounding rock stability
upper bound limit analysis
rigid translatory movement element
slip line network
failure mode
