观音岩水电站三期截流设计与施工

观音岩水电站三期截流方式为导流明渠截流。由于导流明渠采用混凝土衬砌，糙率小，截流抛投材料难以稳定。因此，该设计与施工方案从招投标阶段到现场施工阶段进行了优化，在最截流困难时采用大块石串凸出上游挑角进占，既经济又保证了三期截流的圆满成功。

Design and construction of third-phase river closure for construction of Guanyinyan Hydropower Station

The third-phase river closure for the construction of Guanyinyan Hydropower Station is made by diversion open-channel. The diversion channel is lined by concrete with less roughness， and then the dumping materials for the closure cannot be stabilized. Therefore， optimizations are made on the design and construction scheme from the bidding period to the construction period all along； i.e. large rock cages are taken for protruding the advancement of the upstream oriented angle during the most difficult closuring period， which is not only economical， but also ensures the satisfactory success of the river closure concerned.