预应力混凝土箱梁温度梯度荷载下的应力研究  

Research on Stress of Prestressed Concrete Box Girder under Temperature Grandient Load

作　　者：王绍平 WANG Shaoping(W-Municipal Design, Wuxi 214072, China)

机构地区：[1]无锡市政设计研究院有限公司,无锡214072

出　　处：《交通科技》2018年第6期28-31,共4页Transportation Science & Technology

摘　　要：基于实桥测试研究混凝土箱梁温度场分布规律并计算实测温度梯度,考虑最不利太阳辐射和大气温度等气象因素作用,采用有限元法建立混凝土箱梁温度场模型及理论竖向正温度梯度,计算不同竖向正温度梯度下的温度效应,并同现行规范进行比较。研究表明,规范温度梯度得到的上缘应力为实测和理论温度梯度的1.2倍左右。规范对于箱梁下缘应力和挠曲变形的考虑相对保守,在缺乏实测数据时,可采用理论正温度梯度进行温度应力计算。Based on bridge monitoring,the temperature field distribution of concrete box girderis researched and the measured temperature gradientis calculated.Taking into account the maximum solar radiation and atmospheric temperature,the finite element method is used to establish temperature field model of concrete box girder and the maximum vertical positive temperature gradient.The temperature effect under different vertical positive temperature gradientis calculated and compared with the current specification.The research shows that the stress at the top of box girder obtained by temperature gradient of specification is about1.2times of the measured value and the maximum temperature gradient.The stress and flexural deformation at the lower edge of box girder in the specification is relatively conservative.In the absence of the measured data,the maximum positive temperature gradient can be used to calculate temperature stress.

关 键 词：混凝土箱梁 温度场 温度应力 温度梯度 有限元法 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]