护岸不护底水垫塘底板冲刷特性试验研究

针对乌东德水电站下游水垫深厚的特点,坝后水垫塘拟采用护岸不护底布置型式。通过1∶100水工整体模型试验,观测分析了坝后水垫塘底板基岩的冲刷特性。不同型式泄水孔对底板冲刷影响的比较研究表明:在边表孔挑角、中间表孔俯角的布置格局下,较大泄量工况时,底板基岩均受到不同程度的冲刷;表孔挑坎段增设齿坎不能有效减轻底板基岩的冲刷;在边表孔俯角、中间表孔挑角的布置下,底板基岩冲刷较轻微。

Experimental research on bottom scouring characteristics of plunge pool with side-retaining wall and unprotected bottom plate

Due to the deep and thick downstream water-cushion, the bottom of the plunge pool behind the dam of Wudongde Hydropower Station is unprotected but the bank is protected. By 1:100 hydraulic whole model, the scouring characteristics of the bed rock of the bottom is observed and analyzed. The comparative study on the scouring effect of the bottom plate under different flow releasing modes show that in the case of picking angle of side surface outlet and depression angle of middle outlet, the bottom plate is scoured at different degrees under large discharge;the erosion of the bed rock would not be alleviated by building notched sill on the flip bucket;in the case of depression angle of side surface outlet and picking angle of middle outlet, the bed rock ero-sion is relatively slight.