大化水电站二期导流工程导流明渠泥沙运动与冲淤

大化水电站二期导流工程截流前，导流明渠基本堵塞，靠人力及机械清淤无法按时实现截流。经过分析研究，采用主河槽预抛方案提高上游水位，使导流明渠水流速由１．０ｍ／ｓ逐渐增大到３．２５ｍ／ｓ，在１７天内冲走２５．２万ｍ３淤积泥砂，实现了按计划截流。

Sediment Sluicing& Sediment Motion for Construction Diversion of Second Stage on the Dahua Hydropower Station

The amount of sediment in the diversion channel of Dahua hydropower station reached 252 000 m3 which almost blocked up the channel before the second stage of river-damming of diversion construction. Clearing away the sediment by manpower and machine could not realize the riverdamming in a planned way. The employ of throw stones in advance to main river led scheme raisedthe water level of upper reaches and increased the waterflow velocity of diversion channel from1. 0 m/s to 3. 25 m/s, which resulted in the sluicing away of 252 000 m3 sediment within 17 days.Thus damming the river was achieved in a planned way.