基于概率的锈蚀钢筋混凝土桥梁检测维护策略优化

Probabilistic optimum inspection and maintenance strategy for reinforced concrete bridges due to reinforcement corrosion

考虑钢筋锈蚀钢筋混凝土桥梁结构,将基于钢筋局部锈蚀深度的结构损伤强度指标作为表征结构使用性能的退化指标;考虑钢筋锈蚀、损伤检测、维护决策等各种因素的不确定性,给出基于概率的结构使用寿命预测模型和检测维护成本模型;以最大化桥梁经检测维护后的使用寿命期望和最小化检测维护成本为优化目标函数,提出基于Monte Carlo模拟和遗传算法的锈蚀钢筋混凝土桥梁结构检测维护策略优化分析方法;通过算例分析1座钢筋混凝土桥梁30 m跨主梁,得到其检测维护策略的Pareto优化解集。研究结果表明:Pareto优化解集提供了在不同的结构使用寿命期望和检测维护成本预算约束下效益最大的检测维护策略,可为业主或土木基础设施管理部门选择优化的检测维护策略提供决策依据。

Focused on the deterioration of reinforced concrete（RC） bridges due to reinforcement corrosion, the damage intensity of structure based on local pit depth of reinforcement was used to characterize the deterioration of structure. Considering the uncertainty in reinforcement corrosion, damage detection and maintenance decision, the probabilistic calculation models of service life, inspection and maintenance cost were established. Based on the maximization of the expected service life after inspection and maintenance and the minimization of the expected inspection and maintenance cost, a method based on Monte Carlo simulation（MCS） and genetic algorithm（GA） to optimize the inspection and maintenance strategy owing to reinforcement corrosion for RC bridge was proposed. An example of 30 m span girder of RC bridge was calculated to get the Pareto solutions set of inspection and maintenance strategy. The results show that the Pareto solutions can provide the most profitable strategy with different life expectations and economic budgets as well as decision reference to owners or civil infrastructure administrators to choose inspection and maintenance strategy.