某水电站截流方案比选

截流工程是水电工程建设极其重要的环节。针对截流时龙口水力学指标过高,抛投料流失严重的问题,结合某工程实例,通过模型试验对比研究了S型龙口、S型龙口和导沙坎开孔、河床加糙、拦石栅立体加糙四种截流方式的水力学指标变化规律。结果表明,拦石栅立体加糙方案的龙口落差减少率、龙口流速减少率以及龙口单宽功率减少率分别为10%、30%、20%,此外,该方案还能有效减小抛投料流失率,尤其是大块石料等人工特殊料使用量减少率高达67%,大大降低了施工难度和成本。这种方式尤其适用于龙口落差大、流速快、单宽功率大且大块石缺乏的工程。

Comparison and Selection of Closure Plans for a Certain Hydropower Station

Closure plays an exceeding role in construction of water power engineering. Aiming at high hydraulic indexes in closure gap and serious wastage of ripraps, a typical engineering model experiment was used to find the variation rules of the hydraulic indexes between the roughness of river bed closuring and block stone gate contrastively. The research shows that the reducing rate of closure water-head, closure velocity and closure unit-width energy are 10%, 20% and 30% respectively by using stone gate-dimensional bar closure roughening method. Additionally, the wastage rate of ripraps can be reduced. As for the wastage rate of boulders, using stone gate-dimensional bar closure roughening method can reduce the rate for 67%. Therefore, the proposed method can greatly reduce the difficulty and cost. The proposed method is especially suitable to the projects which have large gap, high velocity, large unit-width power and lack of local large stones.