拱坝加固扩建的新型式——广西南丹县拉希双层拱坝设计与施工

南丹县拉希水库双层拱坝是一项加固扩建工程。原已建砌石拱坝高37.75m,有效库容737万m~3,加固扩建采用在上游另建一高55.2m的薄拱坝与原拱坝形成双层拱坝联合受力的方案,使该库有效库容增至2755万m~3。两拱坝间充水,使上游拱坝部分水压力传递给下游拱坝。因而不仅避开在原坝加高,新旧坝体结合困难等问题,而且坝肩稳定条件和坝体应力状况亦有所改善,节省了工程投资。工程已建成并投入运行。

A New Method for Reinforcement and Expansion of Lashi Dam in Nandan County, Guangxi

In order to reinforce the 37. 75m high masonry arch dam and expand the 7. 37M m~3 Lashi Reservoir, a 55.2m high new arch dam has been built right upstream the old one, with the active storage increasing to 27. 55 M m~3. As the area between these two dams are filled with water, part of water pressure on the upstream arch dam can be transmitted to the old one, thus improving the stability condition of abutments as well as avoiding the difficulty of incorporating the new blocks with the old dam in the case of raising the existing one. The project has been completed and commissioned with less investment.