动载下CRTSⅡ型无砟轨道-简支梁桥变形试验研究  

Tests for deformation of a simply supported beam bridge with CRTSⅡ ballastless track subjected to dynamic loads

作　　者：戴公连[1,2] 王蒙 刘文硕 DAI Gonglian;WANG Meng;LIU Wenshuo(College of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Lab for High Speed Railway Construction,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,长沙410075 [2]高速铁路建造技术国家工程实验室,长沙410075

出　　处：《振动与冲击》2018年第7期102-108,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51378503);中国铁路总公司科技研究开发计划资助项目(2015G001-K)

摘　　要：为了研究动载下CRTSⅡ型无砟轨道简支梁桥的变形特征,以现场试验为依托,测试了CRH380A-001型列车以速度240~350 km/h通过纵连板式无砟轨道32 m简支梁桥时梁轨系统的结构变形。通过现场采集和数据分析,得到了桥梁结构的竖横向绝对位移、水平折角及梁端转角,轨道结构的竖横向相对位移和墩梁纵横向相对位移,研究了桥梁的共振速度及动力系数。结果表明:动载下梁体竖向跨挠比最小值为54 000,水平跨挠比最小值为150 000,远大于规范规定最小限值;梁体梁端转角最大值为0.077‰,水平折角最大值为0.119‰,满足规范限值;实测CRTSⅡ型无砟轨道32 m简支梁桥存在二阶竖向共振速度306 km/h及三阶横向共振速度312 km/h,分别与理论共振速度309 km/h和315km/h相吻合;在共振速度附近实测动力系数大于规范规定取值1.084,且最大值达1.18。In order to obtain deformation characteristics of a simply supported beam bridge with CRTS II ballastless track under dynamic loads,based on field tests,structural deformations of the track-bridge system were measured during CRH380A-001 train passing through a 32 m long simply supported beam bridge with longitudinal continuous plate type ballastless track at the speed of 240 to 350 km/h.Through signals collecting on site and data analysis,vertical and transverse absolute displacements,horizontal break angle and beam-end rotary angle of the beam bridge structure,vertical and transverse relative displacements of the track structure and relative displacements of the pier beam were obtained.The resonance speed and dynamic coefficient of the bridge were studied.The results showed that under dynamic loads,the minimum vertical ratio of span to deflection of the beam is 54 000,the minimum horizontal one is 150 000,they are far larger than the minimum limit values in the code;the maximum values of the rotary angle at the beam-end and the beam horizontal break angle are 0.077‰and 0.119‰,respectively,they are smaller than the limit values in the code;furthermore,the simply supported beam bridge with CRTS II ballastless track has the second-order vertical resonance velocity of 306 km/h and the third-order transverse resonance velocity of 312 km/h obtained with actual measurements,they agree well with the theoretical resonance velocities of 309 km/h and 315 km/h,respectively;the dynamic coefficient actually measured near the resonance velocity is bigger than the limit value of 1.084 in the code,its maximum value reaches 1.18.

关 键 词：简支梁桥 CRTSⅡ型板 动载 现场试验 结构变形 动力系数 

分 类 号：U211.3[交通运输工程—道路与铁道工程] U441.3[建筑科学—桥梁与隧道工程]