葛洲坝及三峡工程对上游槽蓄曲线影响探讨

Discussion on impact of the Gezhouba and Three Gorges projects on upstream channel storage curve

影响水面线及槽蓄曲线的因素可概括为河段自然地理状况及水流情势。随着水利水电工程的开发建设,人类活动影响日益凸现。以三峡工程坝址以上河段为例,根据三峡库区大量实测地形和水文资料,遵循水力学分析原理和方法,建立数学、物理模型,研究三峡坝址以上河段在天然、葛洲坝单独蓄水运行、三峡工程二期导流3个不同时期的水面线和槽蓄曲线,探讨了两项水利工程建设对上游槽蓄曲线的影响。分析表明,受工程影响,同蓄量水位抬高,同水位蓄量减小。三峡坝址至双江河段蓄量同为40亿m3,天然时期坝址水位为63.05m,葛洲坝蓄水后坝址水位抬高6.38m,三峡工程二期导流时期坝址水位抬高达8.71m。

The factors affecting the water-surface profile and channel storage curve may be summarized as the physical geographical condition and the flow regime of the river reach. Along with the development and construction of water conservancy and hydropower projects,the impact of human activities are increasing remarkably. Taking the river reach upstream of the dam site of the Three Gorges project for example, on the basis of a lot of observed topographical and hydrological data and in accordance with the principle and method for hydraulic analysis, mathematical and physical models were established to study water-surface profiles and channel storage curves of the Yangtze river reach upstream of the dam site of the Three Gorges project for three different operation periods of the natural river channel, the Gezhouba project's separate operation and the second-phase construction water diversion of the Three Gorges project. The impacts of the two hydropower projects on upstream channel storage curves were analyzed and discussed. Analyzed results showed that due to the hydropower project's impact, the water levels were raised with same storage volumes and the storage volumes were decreased with same water levels, the storage volume of the river reach from the dam site of the Three Gorges project to the Shuangjiang river was 4 billion m\+3, its corresponding water level at the dam site was 63.05 m for the natural channel period, and was raised by 6.38 m after the impoundment of the Gezhouba reservoir and by 8.71 m during the second phase construction diversion of the Three Gorges project.