摘要
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.
作者
胡炜
汤印
谭信荣
喻渝
Hu Wei;Tang Yin;Tan Xinrong;YüYü(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,P.R.China)
出处
《地下空间与工程学报》
北大核心
2025年第6期2141-2147,共7页
Chinese Journal of Underground Space and Engineering
基金
中铁二院重点课题(KSNQ202013)。
关键词
铁路隧道
目标可靠指标
校准法
抗震可靠指标
二次衬砌
明洞
railway tunnel
target reliability index
calibration method
reliability index for seismic resistance
lining
open cut tunnel
