基于广义柔度曲率信息熵的板式轨道脱空损伤识别  

Void Damage Identification of Slab Track Based on Generalized Flexibility Curvature Information Entropy

作　　者：刘渝[1,2] 赵坪锐 徐天赐[1,2] 刘卫星 姚力 LIU Yu;ZHAO Pingrui;XU Tianci;LIU Weixing;YAO Li(MOE Key Laboratory of High-speed Railway Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]西南交通大学高速铁路线路工程教育部重点实验室,成都610031 [2]西南交通大学土木工程学院,成都610031 [3]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道标准设计》2024年第4期48-54,62,共8页Railway Standard Design

基　　金：国家自然科学基金面上项目(52278459);中铁二院工程集团有限责任公司科技研究计划课题(KYY2019138(19-20))。

摘　　要：板式轨道填充层作为轨道结构关键部位,在高频列车荷载和环境共同作用下出现脱空损伤,引起脱空位置轨道结构刚度改变。为有效检测板式轨道的轨道板脱空情况,采用数值仿真分析得到无砟轨道模态信息,利用轨道脱空区域广义柔度曲率局部峰值进行轨道脱空损伤识别。结合广义柔度、均匀荷载面(Uniform load surface, ULS)、曲率和局部信息熵,提出可定位损伤的ULS曲率信息熵,并在CRTS III板式轨道上进行验证。研究结果表明:广义柔度曲率利用轨道脱空前后模态信息计算轨道脱空损伤曲率差,能够有效定位脱空位置;ULS曲率信息熵表征值只需要轨道的一阶模态信息便能够有效地反映轨道脱空位置及面积,且克服了广义柔度曲率需要健康模态信息的不足;轨道对称位置上相同面积脱空的ULS曲率信息熵值相同;ULS曲率信息熵值与脱空面积和厚度成正相关关系;ULS曲率信息熵表征值具有较好的损伤识别敏感性,能够识别小于单个测点布置面积的0.1 m×0.1 m小面积脱空,并且对轨道板边脱空识别敏感性高于轨道板中脱空识别敏感性。The filling layer of the slab track,as the key track structure,suffers cavity under the combined effects of frequent train loads and environment,which results in the change of the stiffness at the void part.In order to effectively detect the void of slab track,the modal information of ballastless track is obtained by numerical simulation analysis,and the local peak value of generalized flexibility curvature in the void area is used to identify the void damage.Combined with generalized flexibility,uniform load surface(ULS),curvature and local information entropy,the ULS curvature information entropy that can locate damage is proposed and verified on CRTS III slab track.The results suggest that the generalized flexibility curvature uses the modal information before and after the track void to calculate the curvature difference of the track void damage,which can effectively locate the void position.The characterization value of ULS curvature information entropy only needs the first-order track modal information to not only reflect effectively the position and area of track void,but also overcome the deficiency of healthy modal information required for generalized flexibility curvature.The ULS curvature information entropy values are no differences when the cavity coverage at the symmetrical position of the orbit is the same;ULS curvature information entropy is positively correlated with void area and thickness.The characterization value of ULS curvature information entropy has good damage identification sensitivity,which can identify the small area void of 0.1 m×0.1 m less than the layout area of a single measuring point,and the sensitivity of void identification at the edge of track slab is higher than that in the middle of track slab.

关 键 词：板式无砟轨道 广义柔度 均匀荷载面 局部信息熵 损伤识别 

分 类 号：U213.2[交通运输工程—道路与铁道工程]