连续刚构铁路桥收缩徐变效应监测与分析  

Monitoring and Analysis on Shrinkage and Creep Effects of Continuous Rigid Frame Bridge

作　　者：程辉[1,2] 王鸣辉[1,2] 梅秀道[1,2] 叶仲涛[1,2] 王翔[1,2] 

机构地区：[1]桥梁结构与健康湖北省重点实验室,湖北武汉430034 [2]中铁大桥局集团武汉桥梁科学研究院有限公司,湖北武汉430034

出　　处：《江汉大学学报（自然科学版）》2015年第4期323-327,共5页Journal of Jianghan University：Natural Science Edition

基　　金：湖北省自然科学基金项目(2013CFA135;2013CFB457)

摘　　要：对连续刚构铁路桥箱梁温度场及桥梁线形进行长期、连续监测,通过主梁跨中下挠的理论与实测对比揭示了连续刚构铁路桥收缩徐变效应。对比了国内外常用收缩徐变估算模型,选择CEB-FIP徐变模型对黄河特大连续刚构桥进行了有限元分析。采用实测温度数据,以箱梁内测温度、外侧温度、顶底板温度梯度、左右侧温度梯度作为箱梁温度场的评判指标,对箱梁1年内的四季温度场分布进行分析。在基于相同温度场的条件下,通过理论值与实测值对比,发现分析成果与实测结果较吻合,说明混凝土的收缩徐变是引起连续刚构铁路桥跨中下挠的主要原因,对比结果还说明通过改善箱梁顶底板应力差能够改善收缩徐变长期效应。For long-term and continuous monitoring of the railway bridge box beam temperature field and the bridge alignment of continuous rigid frame bridge, through the comparison of theoretical and measured value of excessive deflection in the midspan of girder, revealed the shrinkage and creep effects of the bridge. The common used domestic and overseas shrinkage and creep estimation models were compared, and the CEB-FIP creep model was selected for finite element analysis of the Yellow River large continuous rigid frame bridge. With the measured temperature data, and evaluation indexes which were inner and outer temperature of box girder, bottom and top temperature gradient, left and right temperature gradient, to analyze the temperature field distribution of box girder in four seasons in one year. Under the same temperature field, through the comparison of theoretical and measured value, it was found that the analysis results were consistent with the measured results, so it illustrates that the shrinkage and creep of concrete are the main reasons for excessive deflection in the midspan of railway continuous rigid frame bridge, the comparison results also illustrate that the improvement of stress difference of roof and floor of box girder can improve the long-term shrinkage and creep effects.

关 键 词：连续刚构 温度场 线形 CEB-FIP 收缩徐变 

分 类 号：U446.2[建筑科学—桥梁与隧道工程]