腐蚀-荷载耦合作用下耐候桥梁钢及其焊接节点性能劣化研究进展

Research Progress on Performance Degradation of Weathering Steel andIts Welded Joints in Bridges Under Coupling Effects of Corrosion and Load

耐候钢以其可免涂装使用的优越性被广泛应用于桥梁工程,并且是我国钢桥领域将来一段时间大力发展的重要方向。近年来,随着耐候桥梁钢的广泛应用,耐候钢桥焊接节点的腐蚀与疲劳断裂问题也日益突出,这在一定程度上严重影响了耐候钢桥服役性能。因此,迫切需要开展耐候桥梁钢焊接节点腐蚀力学行为与性能劣化预测方法的研究。基于桥梁实际服役工况,耐候钢往往会受到腐蚀-荷载的耦合作用,故全面系统研究腐蚀环境与荷载耦合作用下耐候桥梁钢焊接节点腐蚀行为,量化导致其力学性能劣化的应力腐蚀损伤与疲劳损伤显得尤为重要。通过分析评价国内外关于耐候钢及其焊接节点腐蚀力学行为、腐蚀演化过程模拟与力学性能劣化评估方法的研究现状,建议了针对耐候桥梁钢及其焊接节点性能研究亟待解决的问题,同时介绍了当前的研究新进展,为耐候钢桥相关研究工作的开展指明了方向,旨在消除我国桥梁设计与建设单位对于耐候钢长期性能所存的疑虑,推动耐候桥梁钢在全国规模化应用进程,为今后我国耐候钢桥建设和维护发挥更积极的作用。

Weathering steel(WS)is widely used in bridge engineering because of its advantage of uncoated application.And it is an important direction for the development of steel bridge in China in the future.In recent years,the corrosion and fatigue fracture of the welded joints in WS bridges have become increasingly prominent with the application of WS.It seriously affects the service performance of WS bridges to a certain extent.Therefore,it is urgent to carry out the research on the corrosion and mechanical behaviors and the prediction method of properties degradation for the welded joints of WS in bridges.According to the actual service conditions of bridges,WS is often subjected to the coupling effects of corrosion and load.Therefore,it is particularly important to comprehensively and systematically study the corrosion behavior of WS welded joints under the coupling effects of corrosion and load,and quantify the stress corrosion damage and fatigue damage resulting in the deterioration of its mechanical properties.In this study,the research status of corrosion and mechanical behaviors,simulation methods of corrosion evolution,and evaluation methods of mechanical property degradation for WS and its welded joints was reviewed and analyzed.And the urgent issues to be solved with regard to the research on the properties of WS and its welded joints were proposed.In addition,the current progress was introduced.These point out the direction for the related researches on WS bridges,aiming to eliminate the doubts of bridge design and construction units for the long-term performance of WS,and pushing forward the large-scale application progress of WS in bridges in China.This study can play a more active action in the construction and maintenance of WS bridges in the future.