水底隧道管片构件耐久性失效风险研究

拟建造在长江口区软土地层中的钢筋砼盾构隧道管片结构 ,在对其耐久性的影响因素进行分析的基础上 ,结合工程的环境条件提出了基于结构可靠度理论的钢筋砼构件耐久性失效风险的计算方法 ,并以上海崇明越江通道工程为例 ,采用蒙特—卡罗法 (MonteCarlo)计算了结构耐久性的失效风险 ,并讨论了各主要因素对耐久性失效风险的影响程度 ,从而取得了水底隧道钢筋砼管片构件耐久性失效风险分析的量化指标。文中提出的方法采用可靠性动态模型模拟结构耐久性失效风险的变化过程 ,包括利用随机事件之间的逻辑运算处理多因素影响的结构耐久性问题 ,为建立多因素影响下耐久性的计算模型提供了一条思路

A Study on Risk of Durability Failure of the Segments for Underwater Tunnel

Based on analysis of factors influencing th e durability of segments i n reinforced concrete shield tunnel to be built in soft soil strata in Yangtze R iver Delta Area, considering the environment of the project, a calculation metho d for the risk of durability failure for reinforced concrete elements was sugges ted, taking the reliability theory of the structure as its basis. For the projec t of passage across the Yangtze River in Chongming, Shanghai, the Monte-Carlo M e thod was applied to estimate the risk of durability failure of the structure. Th e influence of the main factors on the durability failure was discussed and the quantitative indexes for analyzing the factors influencing the durability of seg ments in reinforced concrete shield tunnel under water were gained. A dynamic mo del of reliability was used to simulate the process of durability failure of the structure, including use of logic operation between the random cases to treat t he structure durability influenced by multi-factors, which gives an idea for se tting up a model for calculating durability with multi-factors.