中文摘要：

简支梁桥多跨连续布置带来大量伸缩缝,对行车舒适性和结构维护造成不利影响,因此用连续桥面板代替伸缩缝正成为改进该类桥梁性能的一种处理方式。但是对这种部分连续的桥梁结构,其力学分析理论尚不完善,阻碍了相关的工程应用和优化。因此,针对连续桥面简支梁桥,提出了一种带边界转动弹簧的简支梁模型,弹簧刚度通过对连续桥面和相邻简支梁的拉压、弯曲和剪切分析得到。基于该模型,可以用类似于传统简支梁的分析方法,对这种非传统的桥梁结构进行静力和动力特性分析,获得该类桥梁静力变形、内力、自振频率与模态的计算公式。实例计算表明,由理论公式得到的边界转动弹簧刚度与三维有限元分析结果吻合;采用考虑边界转动弹簧的模型后,桥梁静力挠度、应变、自振频率的计算值接近实桥测试值,优于普通简支梁计算结果,因此可以用于连续桥面简支梁桥的力学分析。

英文摘要：

Because a multi-simple-span bridge introduces many expansion joints that negatively affect the riding comfort and structural maintenance, a continuous deck is becoming an alternative to the expansion joints to improve the performance of this kind of bridge. However, the method for the mechanical analysis of this partially continuous bridge structure is deficient, and the application and optimization are impeded. In this paper, a model for a simple-supported beam with boundary rotational springs is presented to analyze the mechanical properties of a multi-simple-span bridge with a continuous deck, in which the spring stiffness is obtained from the tensional, bending and shearing analyses of link slabs and adjacent bridge girders. Based on this model, the static and dynamic performances of a unconventional bridge structure are analyzed using the method similar to that applied on a conventional simple-supported girder bridge, and the equations of static displacement, intemal force, natural frequency and vibration mode are obtained. The numerical analysis of a practical bridge suggests that the stiffness of a rotational spring from a theoretical equation agrees well with that from 3D finite element analysis. The static deflection, strain and natural frequency from the model considering the boundary rotational spring are closed to the test results of a bridge, and better than those obtained from the model of a simple-supported beam. Thusly, the new method can be applied in the mechanical analysis of a multi-simple-span bridge with a continuous deck.