斜拉桥破损诊断技术的研究

针对钢筋腐蚀、疲劳、预应力松弛和桥梁整体倾斜或变形所引起的斜拉桥局部破损,以使用了15年的永和斜拉桥为研究对象,对斜拉桥破损诊断技术进行了研究,对该桥的破损位置进行了定位,对其破损程度进行了评价.利用有限元分析和现场振动测试结果,对破损前后的模态参数进行分析,提取了对破损状况较敏感的模态曲率作为斜拉桥破损诊断的参数,并从模态参数中选取部分点的分量,导出了可以指示斜拉桥桥面(主梁)大概损伤位置的损伤指标Id,可用以识别出斜拉桥发生破损的区段及破损程度.研究成果为永和斜拉桥的养护维修方案提供了技术支持.

A study of damage diagnosis technique for cable-stayed bridge

Considered local damage due to steels corrosion, fatigue, prestress relaxation, whole bridge incline and distortion, this paper studies damage diagnosis technique of the cable-stayed bridge and determines the location and size of damages for Yonghe Cable-stayed Bridge, which has been used for 15 years. By the finite element analysis and field vibration test, damaged and undamaged modal parameter is analyzed and curvature mode shape, which is sensitive to damage state, is introduced as possible candidate for identifying and locating damage in the cable-stayed bridge. Selecting the components of partial measured point from modal parameter, this paper introduces the damaged index which can detect the possible damaged location of the cable-stayed bridge deck and identifies the damaged region and degree for Yonghe Bridge.By the proposed method , damage diagnosis technique can be successfully applied in an in-service bridge and provides the help for rehabilitation program of Yonghe Bridge.