浅谈沙河超大U形薄壁预应力渡槽槽片预制

Brief Discussion on the Slotted Vane Precast of the Super U-shaped Thin-wall Prestressed Concrete Aqueduct in the Shahe River

南水北调中线沙河渡槽工程是目前世界上规模最大的渡槽工程之一，受自身工程大体积、薄壁、钢筋、钢绞线布置密集、需一次浇筑成型等条件限制，槽片预制过程中暴露出诸如混凝土外观质量缺陷等问题，曾一度被认为是无法克服的难题，通过各参建单位技术人员分析原因、研究方法、并在工程施工过程中不断改进，直至问题解决，总结出不少行之有效的解决办法，积累很多施工经验，为以后类似工程的施工提供参考。

The Shahe aqueduct engineering in the central line of the South-to-North Water Diversion Project is one of the largest aqueduct pro- jects in the world at present. By the restriction of its bulk mass, thin-wall, steel bar and steel strand densely packing and one-time-concreting sha- ping, some problems arise in the process of the prefabrication of the slotted vane, such as the appearance defect of the concrete. It has been con- sidered as an aporia that could not be overcome at one time. Thanks to the construction units and technical personnel, they analyzed the cause, studied the method and kept the continuous improvement, and solved the problems. They summed up many effective solutions and accumulated a lot of construction experience,which offered the reference for the future similar engineering construction.