基于长期监测数据的大跨桥梁结构伸缩缝损伤识别

Damage identification of expansion joints in long span bridge using long-term monitoring data

以润扬大桥悬索桥148 d的健康监测数据为对象,通过分析伸缩缝位移和环境条件的相关性,去除了温度、交通荷载等环境条件对伸缩缝位移的影响,并建立了桥梁伸缩缝的状态监测与评估方法.分析结果表明:温度、交通荷载与伸缩缝位移具有显著的相关性,位移随着温度升高而变大,随着交通荷载的增强而减小;风速和位移的相关性十分微弱,风对伸缩缝位移的影响可以忽略不计;采用均值控制图的方法能够识别出由于结构损伤引起的伸缩缝位移1.0%的异常变化,实现了伸缩缝异常状态的有效监测与识别.

Taking 148 d health monitoring data of Runyang suspension bridge as the study object,the effects of temperature,traffic loading and other environment conditions on the expansion joint displacements are eliminated based on the analysis of displacements and environmental conditions.And,the monitoring and assessment method of bridge expansion joints is presented.The results reveal that temperature and traffic loading have remarkable correlation with displacements.The displacements are observed to increase with the increase of temperature and decrease with the increase of traffic loading.The correlation between wind speed and displacement is very weak and the effects of wind on the displacements can be ignored.The 1.0% abnormal changes of expansion joint displacements are detected using the mean-value control chart and hence the monitoring and identification of expansion joints can be realized.