部分预应力混凝土在铁路桥梁上的应用

Application of Partially Prestressed Concrete in Railway Bridge

本文简要介绍了部分预应力混凝土(P.P.C.)在国内外的应用情况,并结合P.P.C.梁的特点介绍了它的主要设计方法,着重分析了这一新技术用于铁路桥梁的可行性、使用性能的优越性与经济效益,以及应进一步研究的主要问题。预应力度是P.P.C.结构设计中的一个重要概念。本文提出按结构的使用要求将预应力度分为三级,并针对铁路桥梁建议了使用阶段容许开裂的P.P.C.梁的缝宽限值与缝宽计算方法。

A brief introduction on the application of partially prestressed Concrete (P.P.C.) at home and abroad and its main design method concerned to the Characteristics of P.P.C. beam is presented in this paper. The feasibility in applying this new technology to railway bridges, the advantage of its utility behaviour,its economic benifit and key problems that shall be further studied are discussed in particular. The prestressing degree is an important concept in P.P.C. structure design.It is proposed that the prestressing degree may be devided into three grades according to the requirements in structure services. The limited crack width of P.P.C. beams and its computational method in working stage aimed at the railway bridge are also recommended.