洺河渡槽大跨度三向预应力结构设计

Structural design of three-way prestressed for Minghe Aqueduct

南水北调中线工程洺河渡槽设计采用输水结构与纵向承重结构相结合的三槽互联三向预应力新型结构,渡槽跨度40 m。该渡槽规模巨大,大部分设计内容超越现有规范。在设计中:采用减震支座、防落梁、防碰撞等装置消减地震的影响;采用保温隔热材料对渡槽进行保温隔热设计;宽缝止水应用了新型可更换止水装置。通过模型试验验证,采用上述新型结构设计的渡槽是安全可靠的。

In the Mid-Route of South-to-North Water Transfer Project, the Minghe Aqueduct is designed to be a new type of three trough interconnected and three-way prestressed reinforced concrete structure, combining water conveyance structure with longitudinal bearing construction. The length of the single span of the aqueduct is 40 meters. The size of the aqueduct is large, so most of the design elements beyond the current design standard. The first part of the paper introduces the design method of the new structure and the new idea that use damping device including vibration-absorbing supports, antl-falling beams, and bumpers etc. to reduce the effect of the earthquake. Then the method of using heat insulating material is brought forward to reduce temperature effect on the aqueduct. In the end, the utility of the new type replaceable sealing device is introduced. By the model test, it proved that the aqueduct designed by the new type structural is safe and reliable.