湫湖灌区1号过水桥改造工程设计与计算

Design and Calculation of No.1 Overflow Bridge Reconstruction Project in Qiuhu Irrigation Area

过水桥在丘陵灌区应用十分广泛,为丘陵地区跨流域调水提供了便利基础条件。湫湖灌区1号过水桥改造,为满足过水桥的设计过流能力及减少占地等要求,使改造后过水桥的断面和跨度均有所增加。过水桥30 m跨度槽身采用后张法预应力技术,通过三维有限元分析计算,表明通过预应力钢筋的施加,可以大大减少运行期的混凝土拉应力,提高结构的安全度。

The overflow bridge is widely used in the hilly irrigation area, and provides the convenient basic conditions for the interbasin water transfer in the hilly regions. In order to meet the requirements of the design discharge capacity of overflow bridge and reduce the land occupation, the reconstruction of No.1Overflow Bridge in Qiuhu Irrigation Area can make the section and span of overflow bridge all increase after reconstruction. The post-tensioning prestressing technology is adopted for the 30 m-span groove body of the overflow bridge. The result of three-dimensional finite element analysis and calculation shows that the concrete tensile stress can be greatly reduced during the operation by the application of the prestressed steel bar, and the safety of the structure is improved.