轨道交通基础设施杂散电流腐蚀疲劳损伤机理与全寿命监测系统

Fast development of the rail transit is a national strategy of China. However, the stray current corrosion is a potentially fatal hazard to the service safety of the rail transit. Considering the two major infrastructures, e.g., reinforced concrete bridges and buried metal pipelines, there are four parts in this project, i.e., mechanisms of the stray current corrosion, evolution of the corrosion, mechanisms of the corrosion fatigue damage and life-cycle corrosion monitoring system. Firstly, the corrosion mechanisms of the cathodic and anodic regions located on the metals resulted from the stray electric fields are profoundly revealed based on the electrochemical corrosion kinetics and the experiments of quantitative microscopic analysis. Secondly, the distribution model is established to investigate leaking process of the dynamic stray current into reinforced concrete structures and soil buried pipelines, and then the algorithm of the particles field coupling the stray field close to the cathodic and anodic sites is established based on the transport theory of the porous media. Thirdly, investigate the corrosion fatigue model of the steel bar and prestressed steel strand, and then achieve the bond-slip relationship of the reinforced concrete system by coupling the high-speed train fatigue load and the stray current corrosion, and finally obtain the corrosion-fatigue-performance degradation model of the reinforced concrete beams. Finally, explore the life-cycle hybrid networking mechanisms incorporating power line and wireless communication, and then investigate the transmission mode satisfying the stray-current-monitoring service quality of the rail transit，and finally develop the data mining algorithms based on the transparent computing and storage. This project has the significant academic value, remarkable economic benefits and broad application prospects.

快速发展轨道交通是中国战略需求，然而杂散电流腐蚀是重大安全隐患。针对钢混桥梁与埋地金属管线两类重要基础设施，按杂散电流腐蚀机理、发展演化规律、腐蚀疲劳损伤机制与全寿命监测展开研究。首先，基于电化学动力学，结合定量微观测试，揭示杂散电场作用下金属材料阴阳极局部区域腐蚀机理；其次，建立动态杂散电流在钢混结构及埋有管线土壤内的分布模型，进而结合多孔介质粒子传输理论，得到耦合杂散电场下阴阳极局部区域粒子场演化计算方法；第三，建立钢筋和预应力钢绞线腐蚀疲劳模型，得到耦合列车疲劳荷载和杂散电流腐蚀作用下钢混构件的粘结滑移本构，进而建立预应力钢混梁杂散电流腐蚀疲劳性能退化模型；第四，探索电力线与无线异构通信的全寿命组网机制，研究满足轨道交通杂散电流腐蚀监测网络服务质量的传输模式，建立腐蚀监测数据挖掘方法和基于透明计算的在线运算存储平台。本项目具有重要的学术价值与显著的社会、经济效益和广阔的应用前景。

截至到2019年底，中国高铁营业里程达3.5万公里，居世界第一。轨道交通是有效缓解中国幅员辽阔、城市人口密集下运力压力的最有效途径，亦是推动国民经济快速、健康发展的重要载体，必将在相当长的时期内起到显著的牵动作用。城市人口密集、建筑密集、地下管网复杂的现状下，杂散电流长期腐蚀已成为轨道交通运营、周边生命线工程服役的重大安全隐患。轨道交通杂散电流腐蚀机理、疲劳损伤机制与全寿命监测等研究势在必行。. 本项目聚焦于杂散电流对下部钢混结构及周边生命线工程的劣化问题，采用理论研究、数值模拟与实验验证相结合的方法，在轨道交通杂散电流腐蚀机理、轨道交通杂散电流腐蚀发展演化规律、轨道交通杂散电流腐蚀疲劳损伤机理、轨道交通杂散电流腐蚀全寿命监测物联网方面取得了系列创新性成果。基于腐蚀电化学动力学理论，结合定量微观测试分析实验，揭示了轨道交通杂散电流对钢混结构与埋地管线的腐蚀机理；建立了耦合轨道交通杂散电场与局部环境介质粒子场分布演化模型，得到了杂散电流复杂动态极化对阴阳极腐蚀影响规律；应用杂散电流腐蚀和列车疲劳荷载同步耦合试验，建立了钢混构件腐蚀疲劳性能退化模型和预测方法；开发了杂散电流腐蚀监测系列传感器，构建了基于无线通信的杂散电流腐蚀全寿命监测系统。此外，通过挖掘分析上述成果，从轨道交通系统本身和下部结构两方面，提出了高铁杂散电流腐蚀防护具体措施。. 本项目的研究工作，从耐久性的层面为轨道交通的安全服役提供基础理论、实用方法和核心技术。本项目具有重要的学术价值与显著的社会、经济效益和广阔的应用前景。