高墩大跨度上承式连续钢桁梁桥温致变形规律  

Temperature Induced Deformation Laws of High Pier and Long Span Deck Continuous Steel Truss Bridge

作　　者：宋楠 严国兵 张宏程 张勇 冯鸿蕾 SONG Nan;YAN Guobing;ZHANG Hongcheng;ZHANG Yong;FENG Honglei(Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;China Railway Kunming Group Corporation Limited,Kunming 650011,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [2]中国铁路昆明局集团有限公司,昆明650011

出　　处：《铁道建筑》2023年第4期42-46,共5页Railway Engineering

摘　　要：桥梁的纵向位移受活载影响较小,温度效应是影响大跨度钢桥变形行为及受力规律的重要因素,直接关系到桥梁结构安全。本文以墩高154 m,孔跨布置(108.0+151.5+249.0+151.5+108.0)m的上承式连续钢桁梁为背景,依据桥梁监测数据分析了高墩大跨度上承式钢桁梁桥包括结构温度场时变特征,以及桥梁支座位移、桥面纵向位移、温度零点等随温度及时间的变化规律。结果表明:钢桁梁桥温度场在时间维度上存在明显变化,相对于年温度场的变化,大桥日温度场变化较为显著;在同一大气温度条件下,各测点温度波峰出现的时间存在时滞效应;两侧桥台处支座及伸缩缝位移与日温差变化关联性较强。桥梁边墩支座纵向位移与温度近似呈线性关系,但中墩支座活动性能不良,说明在环境温度作用下,支座未能克服桥梁上部结构自重引起的摩阻力,桥梁结构的整体受力与理想设计状态有所差异;由于支座摩阻力不可忽略,桥梁温度零点位置随着温度的变化而发生漂移,且与原设计位置偏差较远,导致各测点纵向位移和日温差的相关性与原设计状态存在偏差。The longitudinal displacement of bridges is less affected by live loads,and the temperature effect is an important factor affecting the deformation behavior and stress laws of long span steel bridges,which directly affects the operational safety of bridge structures.Taking the deck continuous steel truss girder with a pier height of 154 m and a span arrangement of(108.0+151.5+249.0+151.5+108.0)m as the background,based on bridge monitoring data,the time-varying characteristics of the structural temperature field,bridge bearing displacement,longitudinal displacement of the bridge deck,temperature zero,and other changes with temperature and time in the high pier and long span deck steel truss bridge were analyzed in this paper.The results show that there is a significant change in the temperature field of the steel truss bridge in the time dimension,and the daily temperature field of the bridge changes more significantly compared to the annual temperature field.Under the same atmospheric temperature conditions,there is a time-delay effect at the temperature peak time of each measurement point.The displacement of bearings and expansion joint at both abutments has a strong correlation with the daily temperature difference.The longitudinal displacement of the bridge side pier bearing is approximately linear with temperature,but the poor activity performance of the middle pier bearing indicates that under the action of environmental temperature,the bearing cannot overcome the frictional resistance caused by the weight of the upper structure of the bridge,and the overall stress of the bridge structure is different from the ideal design state.Due to the fact that the frictional resistance of the bearing cannot be ignored,the zero position of the bridge temperature shifts with temperature changes and deviates significantly from the original design position,resulting in deviations in the correlation between the longitudinal displacement and daily temperature difference of each measurement point from the original design sta

关 键 词：铁路桥梁 变形温度零点 健康监测 上承式连续钢桁梁桥 支座位移 时滞效应 

分 类 号：U448.13[建筑科学—桥梁与隧道工程]