官地水电站RCC大坝泄洪底流消能技术研究与应用

Study on Underflow Energy Dissipation Technology of High RCC Dam's Flood Discharge

官地水电站大坝为碾压混凝土重力坝,坝身泄洪采用底流消能形式,具有落差大、流速高、单宽流量大、单宽泄洪功率大的特点,其高坝泄洪底流消能防冲的规模和技术难度在国内外当属前列。根据大坝的结构布置特点,结合模型试验研究,对溢流表孔宽尾墩、溢流坝面掺气减蚀设施、消力池连续跌坎等结构设计进行关键技术研究和试验验证,确定了官地大坝溢流面泄洪底流消能体形方案。

The dam of Guandi Hydropower Station is a RCC gravity darn, in which, the energy dissipation through underflow is employed for the dam flood discharge. With a high discharge power per unit width, it is characterized by high drop, high flow velocity and strong discharge power per unit width. The scale and technical difficulty involved in underfiow energy dissipation of this dam is rarely met in domestic and international fields. Based on structure and outlet features of Guandi RCC gravity dam, an experimental research is carried out to study and verify the key technologies in structure design of flaring gate piers of overflowing orifices, aeration facilities for cavitation alleviation of overflowing surface, and a continuous bottom drops of stilling basin. The underflow energy dissipation scheme for the overflowing dam flood discharge of station is finally determined.