Abstract: Taking sediment basin of small and medium hydropower station as the research object, the reasonable values of the harmful sediment particle size, the turbulence modified coefficient, the sediment deposition rate and the dry density of sediment deposition were selected on the base of quasi hydrostatic settlement method. And the calculation method without sediment data for dredging and scouring sediment basin was proposed. The harmful sediment particle size was selected according to the rated head of the sediment basin, the mean annual sediment content, the scale of engineering, the performance of wear resistance as well as the manufacturing and processing quality of hydraulic turbine material. The turbulence modified coefficient was selected according to the actual motion rules of sediment. The sediment deposition rate was selected according to the hydraulic design handbook. The dry density of sediment deposition was selected according to the prototype observation, the model test and the operation practice. Taking Mazihe first-grade hydropower station as an example, the calculation indicates that the calculation result of the calculation method without sediment data for dredging and scouring sediment basin is in accordance with that of the model test. The actual 10-year operating effect of the hydropower station shows that it is feasible to design sediment basin of small and medium hydropower station by using the proposed calculation method.

Key words: hydraulic engineering, hydropower station, sediment basin, sediment, scouring calculation

摘要： 以中小型水利水电站沉沙池为研究对象，在准静水沉降法基础上，选取了危害泥沙粒径、紊动修正系数、泥沙沉降率、泥沙淤积物干密度的合理值，提出了无泥沙资料的沉沙池冲洗计算方法。危害泥沙粒径根据沉沙池额定水头、多年平均含沙量、工程规模、水轮机材料的耐磨性能及加工制造水平选取，紊动修正系数按泥沙实际运动规律选取，泥沙沉降率根据水工设计手册选取，泥沙淤积物干密度结合国内原型观测和模型试验及运行实践选取。以麻子河一级水电站为例进行计算，计算表明：无泥沙资料的沉沙池冲洗计算方法的计算结果与模型试验一致。水电站10年来的实际运行效果显示：基于该方法的中小型水电站沉沙池设计是切实可行的。

关键词: 水利工程, 水电站, 沉沙池, 泥沙, 冲洗计算