文章针对目前弯桥设计中广泛采用的杆系理论没法准确分析结构的实际受力特性的问题,提出了用于弯桥结构分析的实体退化系列单元及预应力空间效应的两阶段分析法,并用一数值算例对其进行了验证。以一实际P.C.弯桥为背景,对其成桥状态下结构的空间受力特性进行了研究,对预应力效应进行了评估,对正应力沿横向分布情况进行了分析,并将其与杆系理论分析结果进行了比较。研究发现:P.C.曲线箱梁桥的空间受力特性明显,在设计计算时其内力不均匀系数宜取1.15～1.20;应用该方法进行P.C.弯桥的空间受力分析是可行的、可靠的,实现了对预应力空间效应的准确分析,为完善P.C.弯桥设计提供了依据。 Aiming at the problem that the rod theory which is widely used in the design of curved bridges can not accurately analyze the actual stress characteristics of the structure, a two-stage analysis method of solid degradation series elements and prestressing space effect for bending bridge structure is proposed. It is verified with a numerical example. Based on an actual PC curved bridge, the space force characteristics of the structure under its bridge condition were studied, and the prestressing effect was evaluated. The transverse distribution of normal stress was analyzed and compared with that of the rod system The theoretical analysis results are compared. The results show that the PC curved box girder bridge has obvious space force characteristics, and its internal force inhomogeneous coefficient should be 1.15 ~ 1.20 in design and calculation. It is feasible, reliable and achievable Accurate analysis of the spatial effect of prestress provides a basis for improving PC curved bridge design.