盾构隧道结构状态导向维护的检查策略

Inspection is the primary method of obtaining operational condition of structure, and it is also the basis for carrying out service state assessment, degradation prediction and maintenance. The shield tunnel structure generally adopts regular inspection method in engineering practice, regardless of the influence of service state and its degradation. Machinery, electronics and other industries proposed the condition-based maintenance, which divides the maintenance object into normal state and failure state when developing inspection policy. Unlike the above industries, the service performance evolution of shield tunnel structure has multiple states. This project intends to propose an inspection policy based on the service state of shield tunnel structure, which can dynamically control the inspection interval. The mathematical model of inspection policy will be established. The characteristics of degradation trend for different shield tunnel structures will be investigated, and the applicability of inspection policies will be investigated with different degradation mode of shield tunnel structure. Decision optimization and strategy evaluation models for inspection policy under the multi-objective constraints of maintenance cost, safety index and inspection validity will be established, and different inspection policies will be compared to prove the technical advancement. In this way, this research aims to form the optimal inspection policy of state-oriented maintenance for shield tunnel structure.

检查是获取结构运行状况的主要手段，也是开展状态评估、退化预测和维修的基础。工程中盾构隧道结构一般采用定期检查方式，不考虑结构退化及状态的影响。机械、电子等行业提出了基于状况的维护方法，在制定检查策略时将维护对象分为正常-失效两种状态。与上述行业不同，盾构隧道结构的服役性能演化是多状态的。本项目拟提出一种依据盾构隧道结构服役状态对检查时间间隔进行动态控制的检查策略，并建立检查策略的数学模型；分析盾构隧道结构的退化趋势特征，考察检查策略与盾构隧道结构退化模式的适用性；构建维护成本、安全性和检查有效性等多目标约束下的决策优化和策略评价模型，比较不同检查策略的先进性，以此形成盾构隧道结构状态导向维护的最优检查策略。

工程中盾构隧道结构一般采用定期检查方式，缺少对结构退化历程和当前所处状态的考虑，因此其检查策略难以优化。本项目研究了随机过程，比例风险模型和时间序列模型等数据驱动的服役性能预测方法，建立了隧道结构服役性能预测模型；在此基础上，提出了具有动态性的检查计划函数模型，构建了检查计划函数的合理化数学形式，分析比较了传统周期性检查与检查计划函数法在隧道结构全寿命周期内的维护效果差异；提出多状态导向维修规则，并与传统的修复性维护方法和预防性维护方法中的维修规则进行了比较，以结构安全性为约束条件，以最小化隧道结构服役寿命期内的维护成本为目标函数，给出了隧道结构维护策略优化问题的数学框架和网络穷举优化算法。通过对现实问题的提炼总结，基于若干算例的数值试验，得到了可用于指导应用实践的结论。项目成果可用于制定盾构隧道结构状态导向维护的检查计划，构建决策优化和策略评价体系，形成维护方案最优化方法，为科学制定检查策略提供理论支持。