Study on Effect of Spillway Trough on Spillway Crest Length of Sand Basin

In order to increase the effective length of spillway crest and to reduce the spillway crest’ s sediment concentration, the traditional sand basin has been improved by adding spillway trough on spillway crest site of sand basin. Based on the model test, the influence of spillway trough on spillway crest length has been analyzed; the quantitative equation is derived between the length of spillway trough and the water head of spillway crest. The verifying of surveying data indicates that the results of calculation and surveying are accord with each other well, and this quantitative equation can give reference to the design of practical spillway trough.