大跨度铁路混凝土斜拉桥收缩徐变计算方法研究  

Study of Creep and Shrinkage Calculation Method for Long-Span Concrete Railway Cable-Stayed Bridge

作　　者：陈英贵 CHEN Ying-gui(China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China;China Railway Construction Bridge Design and Research Branch,Wuhan 430063,China;China Railway Construction Laboratory of Bridge Engineering,Wuhan 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063 [2]中铁建大桥设计研究院,湖北武汉430063 [3]中国铁建股份有限公司桥梁工程实验室,湖北武汉430063

出　　处：《世界桥梁》2020年第S01期89-93,共5页World Bridges

基　　金：浙江省交通运输厅科研计划项目(2017002);中铁第四勘察设计院集团有限公司科技研发项目(2015K14,2020K004)。

摘　　要：针对国内外普遍采用的收缩徐变模型(经验模型)计算结果差异较大的情况,以大跨度铁路混凝土斜拉桥——瓯江特大桥为背景,对我国现行铁路、公路规范以及欧洲现行规范经验模型进行研究。结合徐变试验数据,对经验模型进行修正,得到混凝土的徐变预测模型(试验拟合模型),比较经验模型与试验拟合模型的长期收缩徐变效应。结果表明:常用经验模型与试验拟合模型的收缩徐变效应(位移、内力和应力)均存在较大差异,经验模型计算得到主梁长期收缩徐变所致的主梁位移明显偏大;开展桥梁实际混凝土材料的收缩徐变试验,建立试验拟合模型,可提高大跨度混凝土桥梁长期收缩徐变的预测精度。The traditional empirical model based shrinkage and creep evaluation method that has been widely used at home and abroad can generate results with big differences.To address this,the empirical models in the current Chinese railway and highway codes and Eurocodes are studied,taking Oujiang River Bridge(a long-span concrete railway cable-stayed bridge)as a case.With the measured creep data,the empirical models were modified to be the creep predication models,namely the experimental fitting models,and by which the long-term shrinkage and creep effects of the empirical and the experimental fitting models were compared.The results show that there are big differences between the shrinkage and creep effects(including displacement,internal force and stress)predicted by the two types of models,the empirical models overestimate the main girder displacements caused by long-term shrinkage and creep effect.Using experimental fitting models modified with the data from concrete materials tests of the real bridge can present more accurate results.

关 键 词：混凝土斜拉桥 铁路桥 收缩徐变 混凝土徐变试验 计算方法 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U448.13[交通运输工程—道路与铁道工程]