氯离子侵蚀环境中衬砌管片服役寿命的贝叶斯动态评估  

Bayesian Dynamic Evaluation on Service Life of Lining Segments in Chloride Ion Erosion Environment

作　　者：邢科航 冯现大[1] 卢彬 鲁瑞 XING Kehang;FENG Xianda;LU Bin;LU Rui(School of Civil Engineering and Architecture,University of Jinan,Jinan 250022,Shandong,China)

机构地区：[1]济南大学土木建筑学院,山东济南250022

出　　处：《济南大学学报（自然科学版）》2023年第4期486-492,共7页Journal of University of Jinan(Science and Technology)

基　　金：国家自然科学基金项目(51809115);山东省自然科学基金项目(ZR2019QEE003);中国博士后科学基金项目(2019M652512)。

摘　　要：为了解决目前大多数衬砌管片服役寿命评估结果过于保守以及隧道寿命预测不准确的问题,提出一种氯离子侵蚀环境中衬砌管片服役寿命的贝叶斯动态评估方法;通过模拟计算衬砌管片可靠度,考虑保护层厚度、混凝土抗压强度和钢筋抗拉强度的不确定性,实现时变状态下氯离子侵蚀导致衬砌管片承载力减小的全过程描述,并利用现有监测数据完成对衬砌管片服役寿命进行动态更新。结果表明:将所提出的方法应用于某盾构隧道工程,当仅考虑氯离子浓度作为寿命终点时,保守估计衬砌管片的服役寿命仅为37 a;在氯离子侵蚀环境中,理论计算和模拟计算显示衬砌管片会在第92年因可靠度不足而达到寿命终点;利用现有观测数据,根据贝叶斯公式对理论数据进行动态更新,衬砌管片可靠度在第88年提前失效,隧道寿命缩减4%,在实际应用中需要提前加强防护以确保隧道能够达到设定年限。To solve the problems that most service life evaluation results of shield tunnel lining segments were too con-servative and tunnel life prediction was inaccurate,a Bayesian dynamic evaluation method for service life of lining segments in chloride ion erosion environment was proposed.By simulating and calculating reliability of lining segments,and considering uncertainty of protective layer thickness,compressive strength of concrete,and tensile strength of steel bars,the whole process of reducing bearing capacity of lining segments caused by chloride ion erosion under time-varying con-dition was described.Existing monitoring data were used to dynamically update the service life of lining segments.The results show that applying the proposed method into a shield tunnel project,when only chloride ion concentration is considered as the end of life,the service life of lining segments is conservatively estimated to be only 37 a.In the chloride ion erosion environment,theoretical calculation and simulation calculation indicate that the lining segments reaches the end of life due to insufficient reliability in the 92nd year.By using existing observation data and dynamically updating theoretical data according to Bayesian formula,the reliability of lining segments fails early in the 88th year resulting in a reduction of 4%in tunnel life.In practical applications,it is necessary to strengthen protection in advance to ensure that the tunnel can complete the set period.

关 键 词：盾构隧道 衬砌管片服役寿命 贝叶斯动态评估 氯离子侵蚀 隧道寿命预测 

分 类 号：U451.4[建筑科学—桥梁与隧道工程]