汉江兴隆水利枢纽工程施工导流设计与实践

汉江兴隆水利枢纽工程坝址区河道开阔,两岸是低-高漫滩,中偏右为主河床,采用二期导流方式施工。坝址区覆盖层深厚,由粉细砂夹砂壤土及厚层粉细砂等组成,抗冲能力弱、透水性强,明渠防冲和围堰防渗是工程施工导流的两个重要关键技术问题。通过水工与泥沙模型试验及二维渗流计算分析,导流明渠采用“守点护线”的防护原则,解决了防冲保护问题;上下游横向围堰与左右侧纵向围堰防渗采用全截断式塑性混凝土防渗墙,布置为圈式封闭形式,避免了渗透稳定破坏。对导流建筑物的设计、运行过程中出现的问题及处理措施作了简要的介绍,可供类似工程参考。

Design and practice of construction diversion of Xinglong Hydro-junction on Hanjiang River

The river channel of Hanjiang River at Xinglong Hydro-junction site is wide. The main channel is on the middle-right part with low or high beach at both banks. 2-staged diversion was adopted in the construction of the project. Due to thicker overburden layer composed of fine sand with sandy loam, thick fine sand etc., the foundation has low anti-scouring and strong permeability, so the anti-scouring and cofferdam seepage prevention are 2 key technical issues in diversion construction. Through the hydraulic and sediment tests as well as 2D seepage calculation, the principle of "preventing the point from souring and protecting the line" was adopted, so the anti-scouring problem was solved. The full cut plastic concrete cutoff wall was applied for the transversal cofferdam and 2 longitudinal cofferdams with the layout form of full closed circular, which avoided the seepage stability failure. The problems occurred in the design and operation of the project and treatment measures are briefed to provide reference for other similar projects.