摘要
膨胀岩遇水产生的膨胀应力对地铁隧道结构的长期安全存在不利影响,前人的研究主要考虑膨胀岩的体积膨胀作用,而对膨胀过程中的软化效应考虑不足。为此,通过室内试验,获取膨胀岩的物质组分、软化特性、膨胀参数,揭示了膨胀岩在膨胀过程中的弹性软化效应。基于湿-温体积膨胀等效的认识,提出了考虑弹性软化的湿温等效模拟方法,给出了弹性软化参数、膨胀等效温度边界条件、膨胀圈的确定方法,建立了湿温软化等效膨胀模拟流程。将上述方法应用于重庆地铁18号线区间隧道砂质泥岩洞段的长期安全评价,结果表明,考虑弹性软化的湿温等效模拟计算得到的膨胀应力比不考虑弹性软化的湿温等效模拟结果更接近于实际。对影响计算结果的膨胀圈厚度、弹性软化程度等进行了讨论,给出了膨胀岩洞段的处置建议。研究结果可供膨胀岩隧道长期安全评价参考,对于防治地下工程膨胀灾害有一定指导作用。
The expansion stress of swelling rock in the contact with water has an adverse effect on the long-term safety of the subway tunnel structure. Previous studies mainly considered the volume expansion of swelling rock, but lacked the consideration of the softening effect during the expansion process. For this reason, through laboratory tests, the material components, softening characteristics, and expansion parameters of swelling rock are obtained, and the elastic softening effect of swelling rock in the expansion process is revealed. An equivalent simulation method of humidity and temperature expansion considering elastic softening is proposed based on the recognition that the volume expansion caused by humidity and temperature are similar. The determination methods of elastic softening parameters, expansion equivalent temperature boundary conditions, and expansion zone are given. The simulation procedure has been established. The above method is applied to the long-term safety assessment of the sandy mudstone section of the interval tunnel of Chongqing Metro Line 18, and the results show that the expansion stress calculated by the new method is closer to reality than the classical equivalent simulation result of humidity and temperature. Finally, the thickness of the expansion zone and the degree of elastic softening that affect the calculation results are discussed. Recommendations for the disposal of the swelling tunnel section are also put forward. This work can be used as a reference for long-term safety evaluation of swelling rock tunnels, and has a certain guiding role in preventing and controlling swelling disasters of underground engineering.
作者
李兆琛
朱勇
周辉
李静
LI Zhao-chen;ZHU Yong;ZHOU Hui;LI Jing(College of Pipeline and Civil Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2022年第S02期497-507,共11页
Rock and Soil Mechanics
基金
国家重点研发计划项目(No.2019YFC0605103,No.2019YFC0605104)
国家自然科学基金专项项目(No.41941018)
中国科学院科研仪器设备研制项目(No.YJKYYQ20200040)。
关键词
深埋地铁隧道
膨胀岩
弹性软化
湿温等效膨胀
deeply-buried subway tunnel
swelling rock
elastic softening
equivalent expansion of humidity and temperature
作者简介
第一作者:李兆琛,男,1995年生,硕士,主要从事城市地下空间长期安全稳定性等方面研究工作。E-mail:Lizhaochen2021@163.com;通讯作者:朱勇,男,1979年生,博士,助理研究员,主要从事城市地下空间、围岩稳定性分析等相关岩土力学方面的研究工作。E-mail:yzhu@whrsm.ac.cn
