目前我国已初步完成铁路隧道极限状态法转轨,建立了铁路隧道结构在自重及围岩荷载作用下的极限状态设计方法,但未对铁路隧道在地震荷载作用下的极限状态法展开详细研究。为进一步完善铁路隧道极限状态设计体系,明确铁路隧道结构抗震目标可靠指标以建立铁路隧道抗震极限状态设计方法,采用校准法对现行铁路隧道衬砌及明洞抗震通用参考图进行了可靠度校准,并基于校准结果提出了铁路隧道抗震目标可靠指标。结果表明:铁路隧道结构抗震可靠指标主要与围岩级别及结构类型相关,具体表现为衬砌可靠指标小于明洞可靠指标,Ⅴ级围岩下结构可靠指标小于Ⅳ级围岩可靠指标;考虑不同围岩级别下各结构的权重系数后,铁路隧道抗震可靠指标的平均值为6.81,大于现行规范提出的铁路隧道结构在自重及围岩压力作用下的目标可靠指标4.2,现行衬砌及明洞的抗震可靠度水平较高;结合铁路隧道抗震通用参考图可靠度校准结果和现行规范中的目标可靠指标,确定铁路隧道抗震目标可靠指标安全等级一级时为4.7,二级为4.2,三级为3.7。
China preliminarily completes the transition of limit state design method for railway tunnel currently and establishes the limit state design method for railway tunnel structure under self weight and surrounding rock load. However, detailed research are not conducted on the limit state method for railway tunnel under seismic load. In order to improve the limit state design system of railway tunnel, clarify the target reliability index of railway tunnel structure for seismic resistance and establish the limit state method for railway tunnel for seismic resistance, the paper calibrated the reliability of railway tunnel lining and open cut tunnel in current general reference maps for seismic resistance by calibration method, and put forward the target reliability index of railway tunnel for seismic resistance based on calibration results. The results show that: The reliability index of railway tunnel structure for seismic resistance is mainly related to the surrounding rock level and structure type, specifically, the reliability index of the lining is significantly lower than that of the open cut tunnel, and the reliability index of the structure under Grade V surrounding rock is significantly lower than that under Grade IV; After considering the weight coefficients of various structures under different surrounding rock levels, the average reliability index of railway tunnel for seismic resistance is 6.81, which is greater than target reliability index of 4.2 for railway tunnel structure under self weight and surrounding rock pressure, the reliability level of the current structure for seismic resistance is relatively high; Based on the calibration results of the current general reference maps of railway tunnel for seismic resistance and the target reliability index in current code, the target reliability index of railway tunnel for seismic resistance is determined to be 4.7 for Level 1, 4.2 for Level 2, and 3.7 for Level 3.
[1] 胡炜, 赵东平, 郑长青.铁路隧道衬砌极限状态法设计验证研究[J].地下空间与工程学报, 2017, 13(6): 1592-1598.(Hu Wei, Zhao Dongping, Zheng Changqing.Research on design verification of limit state method for railway tunnel lining[J].Chinese Journal of Underground Space and Engineering, 2017, 13(6): 1592-1598.(in Chinese))
[2] 赵东平, 喻渝.中英钻爆法铁路隧道设计方法比较研究[J].铁道标准设计, 2014, 58(5): 99-104.(Zhao Dongping, Yü Yü.Comparative research between China and britain on design approach of railway tunnel with drilling-and-blasting-method[J].Railway Standard Design, 2014, 58(5): 99-104.(in Chinese))
[3] 赵万强, 李磊, 王政栋, 等.铁路隧道复合式衬砌极限状态设计研究[J].铁道工程学报, 2015, 32(6): 62-68.(Zhao Wanqiang, Li Lei, Wang Zhengdong, et al.Study on optimizing limit states design of railway tunnel composite lining[J].Journal of Railway Engineering Society, 2015, 32(6): 62-68.(in Chinese))
[4] Azadi M, Ghasemi S H, Mohammadi M.Reliability analysis of tunnels with consideration of theearthquakes extreme events[J].Geomechanics and Engineering, 2020, 22(5): 433-439.
[5] Wang Z C, Hu M G, Lai J X, et al.Reliability analysis method for tunnel structural design: Brief review and relevant prospects[J].Structures, 2023, 55: 1894-1905.
[6] Tian N, Chen J, Zhou N X, et al.Simplified reliability assessment approach for tunnel structures considering the effects of adjacent excavation and soil uncertainty[J].Structures, 2023, 58: 105514.
[7] Fang Y B, He C, Su Y H, et al.Supplement to the reliability index approach and its application to tunnel reliability problems[J].Computers and Geotechnics, 2023, 163: 105767.
[8] 胡炜, 谭信荣, 喻渝.铁路隧道衬砌极限状态法设计软件开发及应用[J].铁道标准设计, 2022, 66(5): 100-105.(Hu Wei, Tan Xingrong, Yü Yü.Development and application of limit state method design software for railway tunnel lining[J].Railway Standard Design, 2022, 66(5): 100-105.(in Chinese))
[9] 童祥, 吕刚, 赵东平, 等.京张高铁八达岭铁路隧道衬砌极限状态设计方法研究[J].铁道标准设计, 2021, 65(3): 118-123.(Tong Xiang, Lü Gang, Zhao Dongping, et al.Research on the design of lining limit state method for badaling railway tunnel of Beijing-Zhangjiakou high-speed railway[J].Railway Standard Design, 2021, 65(3): 118-123.(in Chinese))
[10] 中国铁路总公司.铁路隧道设计规范(极限状态法)(Q/CR 9129-2018)[S].北京: 中国铁道出版社, 2019.(China Raiway Corporation.Code for Design of Railway Tunnel (Limit State Method)(Q/CR 9129-2018)[S].Beijing: China Railway Publishing House, 2019.(in Chinese))
[11] 侯公羽, 韩茹, 黄祥忠.基于响应面法的隧道可靠度分析及其指标确定[J].地下空间与工程学报, 2009, 5(5): 965-971.(Hou Gongyü, Han Ru, Huang Xiangzhong.Reliability analysis of the tunnel and determination of its index based on response surface method[J].Chinese Journal of Underground Space and Engineering, 2009, 5(5): 965-971.(in Chinese))
[12] 余永康, 刘新荣, 刘先珊, 等.随机变量相关性对隧道二衬作用效应的研究[J].地下空间与工程学报, 2019, 15(4): 1138-1143.(Yu Yongkang, Liu Xinrong, Liu Xianshan, et al.Study on random variables correlation to the internal forces of tunnel secondary lining[J].Chinese Journal of Underground Space and Engineering, 2019, 15(4): 1138-1143.(in Chinese))
[13] 边亦海, 黄宏伟, 高军.可靠度理论在确定隧道衬砌合理参数中的应用[J].地下空间与工程学报, 2005, 1(1): 129-132.(Bian Yihai, Huang Hongwei, Gao Jun.Application of reliability theory in determining reasonable parameters of railway tunnel lining[J].Chinese Journal of Underground Space and Engineering, 2005, 1(1): 129-132.(in Chinese))
[14] 胡炜, 赵东平, 谭信荣.基于可靠度理论的隧道洞门结构计算软件开发[J].现代隧道技术, 2018, 55(6): 19-25.(Hu Wei, Zhao Dongping, Tan Xinrong, et al.Development of the software for calculating tunnel portal structure based on the theory of limit state method[J].Modern Tunnelling Technology, 2018, 55(6): 19-25.(in Chinese))
[15] 喻渝, 赵东平, 路军富, 等.铁路隧道概率极限状态设计方法及应用[M].北京: 人民交通出版社, 2017.(Yü Yü, Zhao Dongping, Lu Junfu, et al.Probabilistic limit state design method for railway tunnel and application[M].Beijing: China Communications Press, 2017.(in Chinese))
