岩滩水电站库区长乐排涝工程设计洪水的确定

Determination of Design Flood of Changle Drainage Works in Yantan Reservoir Area

岩滩水电站蓄水致使东兰县长乐乡内涝区排水通道落水洞出口被淹,地下河通道水泄水能力下降,暴雨积水不能及时排泄而引发岩溶浸没内涝。在缺乏水文资料的情况下,根据岩溶河流产汇流特点,暴雨资料,采用堰流公式、洪峰模数法等方法分暗河和明流两部分计算洪峰流量,然后按时段叠加得出设计洪水过程线,为排涝提供依据。

During impoundment of Yantan reservoir, Karst immersion-waterlogging hazard occurred in Changle Town of Donglan County because of reduced discharge capacity of underground-river channel resulting from the submerged sinkhole outlet. Due to lacking of hydrological data, peak flows of underground-river and open flow were calculated by weir formula and flood peak modulus method based on the rainfall data and the runoff characteristics of Karst River, and then the design flood hydrograph was obtained by period superposition, which provided a basis for drainage works. Changle