不同梯度温度作用下曲线桥梁的温度效应分析

梯度温度作用在曲线桥梁中会产生较大的温度应力,这会影响到桥梁结构的安全性和耐久性.文章采用通用有限元程序ABAQUS建立了某曲线梁桥的空间有限元模型,分析了不同国家规范的梯度温度荷载模式下结构的变形和内力.结果表明:不同温度模式的计算结果差距很大,例如采用新西兰规范、中国规范和英国规范的计算结果较为保守；截面最大主应力出现在中腹板与顶板相交的位置；不同曲率半径下的曲线桥梁横桥向应力极值变化较大,顶板的横向配筋应考虑曲率半径的影响.

Analysis of temperature effects of curved bridge under different gradient temperature load

The gradient temperature load can cause great temperature stress in curved bridge,which will influence the safety and durability of curved bridge.The spatial finite element model of a curved box girder bridge is set up through the general finite element program ABAQUS,and the force and deformation of the curved box girder bridge under different gradient temperature load are analyzed according to different national standards in the world.It is proved that there are great differences between the calculation results of the models with different gradient temperature load.For example,the calculation results from British BS 5400 and Specification of New Zealand and Chinese Code JTG D60-2004 are more conservative.The maximum tensile stress appears at the interception of the middle web and top plate in the box girder cross section.The maximum longitudinal stress in the curved bridge changes greatly with different radius of curvature,so the transverse reinforcement design of the top plate should take the effect of the curvature radius into consideration.