连续刚构桥温度应力理论研究

Research on Temperature Stress Theory of Continuous Rigid Frame Bridge

通过阅读大量文献,首先介绍了国内外由温度应力引起的桥梁破坏实例,接着阐述了桥梁结构温度应力的特性和理论计算依据。最后根据工程实例,采用MIDAS有限元软件建立全桥模型,对比分析了上部结构整体升温、降温,正温度梯度和负温度梯度变化下的主梁应力和变形情况。实例表明,温度梯度变化对桥梁的影响比整体升温降温要明显的多,而且负温度梯度变化会对主梁产生拉应力,引起结构破坏。

Through reading a lot of literatures, the paper first introduces the failure of the bridge caused by temperature stress at home and abroad, and then the characteristics of the temperature stress of the bridge structure and theoretical calculation basis are expounded. According to the engineering example, the finite element software MIDAS is used to establish the whole bridge model. The whole heating and cooling, the positive and negative temperature gradients of the upper structure under the change of stress and deformation are comparatively analyzed. The examples show that the influence of temperature gradient on the bridge is much more than that of the whole heating and cooling, and the negative temperature gradient change will lead to tensile stress of the main beam to cause structural damage.