基于柔度差平均曲率的悬臂挡墙损伤识别  

Identification of Damage in Cantilever Retaining Wall Based on Flexibility-difference Mean Curvature

作　　者：刘礼标[1,2] 张永兴[1,2] 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045

出　　处：《公路交通科技》2013年第1期39-44,共6页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(51027004;50878218);长江学者和创新团队发展计划项目(IRT1045)

摘　　要：针对悬臂挡墙的损伤识别问题,提出了基于柔度差平均曲率的挡墙损伤识别方法。该方法引入微分几何理论中曲面上一点的平均曲率概念,通过该点上2个主曲率求其平均曲率。首先利用挡墙损伤前、后模态柔度矩阵求取柔度矩阵差,并以其列元素的平均值作为模态柔度差向量;然后利用中心差分法求得模态柔度差平均曲率作为检测挡墙损伤的新指标(FDMC)。通过对悬臂挡墙的数值模拟研究,结果表明:无论对单处损伤还是多处损伤,该指标都能准确地识别挡墙的损伤位置;根据损伤程度和指标FDMC的相互关系进一步确定单元的损伤程度,且具有较高的识别精度。通过与已有的高斯曲率模态差指标进行比较,验证了该指标的有效性和优越性。To solve the problem of identificating damage in cantilever retaining wall, the identification method of damage in cantilever retaining wall based on flexibility-difference mean curvature is proposed. The concept of mean curvature in differential geometry is introduced to calculate the flexibility-difference mean curvature of two principal curvatures. First, the flexibility difference matrix is calculated by the change in the modal flexibility matrix of retaining wall before and after damage, and each column average value of flexibility difference matrix is used as the elements of the modal flexibility-difference column vectors. Then, the flexibility-difference mean curvature （FDMC） is obtained by central difference method as a new index of damage identification. The result of numerical simulation of cantilever retaining wall indicates that （ 1 ） the damage location in retaining wall, single damage or multiple ones, can be detected accurately by the index; （2） the unit damage extent can be accurately detected via the relation between damage extent and index FDMC with high precision. Compared to Gauss curvature modal difference, the effectiveness and advantage of FDMC are proved.

关 键 词：道路工程 悬臂挡墙 平均曲率 柔度差 损伤识别 损伤程度 

分 类 号：U417.112[交通运输工程—道路与铁道工程] TU476.4[建筑科学—结构工程]