摘要
为简化损伤识别流程,避免动力模型修正的复杂性,首先,将挠度曲线和位移影响线相结合,针对移动荷载作用下的中小跨径桥梁结构提出准静态挠度曲面的概念;其次,基于虚功原理推导挠度曲面的解析表达式,并给出实际应用时的矩阵表达方式;然后,以简支梁和连续箱梁桥为例,提出采用梁损伤前后的挠度曲面差来定位损伤;最后,对一变截面连续箱梁桥的上部结构模型进行静力加载,通过实测挠度数据构建箱梁桥损伤前后的挠度曲面,根据挠度曲面差实现对损伤的定位。结果表明:所提出方法对变截面箱梁同样适用,损伤定位只需根据结构损伤前后的实测挠度数据;挠度差曲面的峰值对应于损伤位置,峰值高低一定程度上体现了损伤程度的变化。
This study incorporates the concept of deflection curves with displacement influence lines in order to propose a new concept of quasi-static deflection surface for short-to-medium span bridges under moving loads.Analytical formulas of deflection surfaces are derived using the principle of virtual work.An alternative form by deflection matrix is given for practical applications.After that,the deflection surface difference of a simply supported beam,as well as a continuous box-girder bridge before and after damage,was used to locate damage.Lastly,the superstructure model of a continuous box girder bridge with variable cross sections was statically tested in the laboratory.Measured deflections were used to construct the deflection surfaces of the box girder bridge model before and after damage.The artificial damage was successfully located using the difference of these deflection surfaces.The analysis results demonstrate that the proposed method is also applicable to box girders with variable sections.Damage localization can be achieved using structural measured deflection data before and after damage.The peaks on a deflection difference surface correspond to the damage locations,and the peak magnitudes reflect the changes in damage severity to some extent.
作者
方圣恩
黄继源
FANG Sheng′en;HUANG Jiyuan(School of Civil Engineering,Fuzhou University Fuzhou,350108,China;National&Local Joint Engineering Research Center for Seismic and Disaster Informatization of Civil Engineering,Fuzhou University Fuzhou,350108,China)
出处
《振动．测试与诊断》
EI
CSCD
北大核心
2022年第2期270-276,406,共8页
Journal of Vibration,Measurement & Diagnosis
基金
国家自然科学基金面上资助项目(51578158)
福州大学“旗山学者”奖励支持计划资助项目(XRC-1688)。
关键词
损伤定位
静力移动荷载
准静态挠度曲面
挠度曲面差
连续箱梁桥模型
damage localization
static moving loads
quasi-static deflection surface
deflection surface difference
continuous box girder bridge model
