基于长期观测的混凝土箱梁温度与应变分析  

Analysis of concrete box-girder temperature and strain based on long term observation

作　　者：雷笑[1] 叶见曙[1] 王毅[2] 吴文清[1] 

机构地区：[1]东南大学交通学院,江苏南京210096 [2]南京市公路建设处,江苏南京210012

出　　处：《江苏大学学报（自然科学版）》2010年第2期230-234,239,共6页Journal of Jiangsu University：Natural Science Edition

基　　金：国家"863"计划项目(2007AA11Z106);国家西部交通建设科技基金资助项目(200331822315)

摘　　要：基于对某预应力混凝土连续箱梁桥为期5年的温度与应变观测,系统地研究了混凝土箱梁截面内最大竖向温差以及各部位混凝土应变随时间长期变化的规律.基于相关性分析提出了一种由环境最高温度对无铺装层和有100 mm沥青铺装层的混凝土箱梁竖向正温差的极限值进行预测的方法,得到的有100 mm沥青铺装层的混凝土箱梁的日最大竖向正温差和箱外日最高温度的相关系数为0.73,在此基础上得到了相应的混凝土箱梁计算梯度温度模式.通过回归分析得到了混凝土箱梁应变增量和最大竖向正温差的关系式,得到的底板纵向日最大应变增量和日最大正温差的相关系数为0.64,由此可对混凝土箱梁应变增量的大小进行评估.The temperature and strain data of a post-tensioned continuous concrete box-girder bridge have been monitored for five years.Based on the measured data,the temperature in the different positions of the concrete box girder was systemically analyzed to extract the temperature variables,including the vertical temperature differences throughout the bridge cross section and the concrete strains in the different aspects of the bridge cross section.A method for predicting the maximum value of the vertical temperature diffe-rences of concrete box-girder with 100 mm asphalt pavement and without pavement was proposed by use of the correlation analysis based on the daily maximum environment temperature.The correlation coefficient between the daily maximum environment temperature and the maximum vertical temperature difference in concrete box-girder with 100 mm asphalt pavement was 0.73.The computational model of temperature difference was developed.The relationship between the maximum vertical temperature difference and the concrete maximum strain increment was established by regression analysis.The correlation coefficient between the maximum vertical temperature difference and the concrete maximum strain increment in the bottom plate is 0.64.The relationship is quite useful in estimating the strain value in concrete box-girder.

关 键 词：混凝土桥梁 温度观测 温度梯度 温度效应 应变 

分 类 号：U448.35[建筑科学—桥梁与隧道工程]