丹江口大坝加高堰顶溢流段施工渡汛试验研究

Hydraulics research on flood-releasing during constructionperiod of heightened scheme of Dangjiangkou Dam

阐述了南水北调工程丹江口大坝加高施工期渡汛时的主要试验成果。通过128m高程平台与三级台阶两个方案的试验成果表明:泄流能力满足设计要求;牛腿安装在封堵门槽后,无阻水现象;坝面平台后存在负压,闸墩工作门槽后有4.0×9.81kPa的负压;水流出平台有脱空现象;挑流水舌打击护坦,而三级台阶方案无打击护坦现象。

The hydraulics study results on flood?releasing during construction period of heightened scheme of Dangjiangkou Dam for Diversion Project from South to North China are represented. The test results obtained from the 128 m elevation platform scheme and three?steps platform scheme show that the discharge capacity can meet the design requirements;the brackets fixed at the downstream of closure?slots wouldnt occur water?resisting phenomenon;the dam surface behind the platform would generate negative pressure, and the negative pressure behind working slot equals to 4.0×9.81 kPa;below the flow separated from the platform a cavity pocket forms; and the jet flow will strike on the apron, as to the three?steps pkatform scheme, the flow passing over it doesnt strike on the apron.