曲线连续梁桥的病害与温度效应

由于曲率的影响，曲线梁桥易产生弯扭耦合作用，因此曲线梁桥的内力、变形计算远比直线梁桥复杂，实际工程中也出现了不少问题。应用有限元方法，以曲线连续箱梁桥为工程背景，对温度荷载作用下曲线连续梁桥的受力与变形特点进行了分析。计算结果表明，温度作用对曲线连续梁桥的内力有显著的影响，容易产生工程病害；原公路桥涵设计规范中对混凝土箱梁竖向温度梯度的规定不够合理；箱梁顶、底板的温差效应是造成曲线连续箱梁扭转的主要因素，而整体升温则是曲线连续箱梁桥直接发生径向偏移的主要原因。这一结论将对改进曲线连续梁桥的设计，具有较强的理论与实践意义。

Diseases of Curved Continuous Bridge and Temperature Effect

The coupling effect of moment and torque will occur in the curved continuous bridge due to the impact of curvature, therefore, the computation of internal forces and deformation is far more complicated than the straight line bridge, and many problems have emerged in curved continuous box-girder bridge in practical engineering. Taking an actual curved continuous box-girder bridge as an example, the features of loading and deformation of this bridge were computed and analyzed under the temperature action by use of finite element method. Numerical computation results show that the temperature action has direct impact on the internal force of curved continuous bridge, and diseases are hence easily induced. Obviously, the relevant provision about the vertical temperature difference of concrete box-girder in the former standard was not reasonable. It was also found that the vertical temperature difference between top flange and bottom flange is the main reason that results in the torsion of curved continuous box-girder bridge, and the integral temperature rise is the main cause that results in the radial displacement.The conclusions obtained have obvious significance both in theory and application to the design and analysis of such curved continuous box-girder bridges.