斜拉桥纵向位移与温度的相关性分析

Correlation Analysis for Longitudinal Displacement and Girder Temperature for a Cable-stayed Bridge

依托南京长江第二大桥健康监测系统实测数据的分析,对斜拉桥纵向位移与温度的关系进行了分析,发现其基本呈现出线性的关系,但在较长时间段里呈现出较弱的非线性关系,这一较弱的非线性关系在对伸缩缝进行安全评估时,可以利用线性关系替代;斜拉桥的非线性热膨胀效应强于悬索桥的非线性热膨胀效应,可以指导斜拉桥运营期的安全预警阈值的设定工作以及桥梁安全状态评估工作,对今后斜拉桥的设计以及养护具有一定的指导作用。

According to the data recorded by the structural health monitoring system of the Second Nanjing Yangtze Bridge, this paper researched the relevance between the girder-end longitudinal displacement and the girder temperature, and found out that they had the linear relationship in terms of short time, but a little bit nonlinear relationship in terms of long time. This little nonlinear relationship could be substituted by the linear relationship when assessing the safety of the expansion joint. The result showed that the nonlinear characteristic of the thermal expansion effect in cable-stayed bridge was stronger than that in suspension bridge, which could be used to guide the alarming value setting for the safety of the cable-stayed bridge. It could provide reference for the design and the maintenance of cable-stayed bridge.