【摘要】 在截流工程中 ,加糙可以使河床底流速降低 ,其降低幅度与河床相对粗糙度有关 ,河床相对粗糙度越大 ,河床底流速降低值越大 ,反之 ,则降低值减小 ;底流速的降低 ,可以有效地减小舌状堆积体长度 ,减少抛投料和缩短截流时间 ,从而降低截流难度更多还原

【Abstract】 In the process of river closure, increase of roughness of riverbed can reduce the flow speed of under-set. The range of reduce is related to the relative roughness of riverbed: The greater the roughness, the greater the range of flow speed decrease is; whereas the smaller the roughness, the smaller the range of the flow speed decrease is. Moreover, decrease of under-set flow speed can reduce the length of the tongue-shapeed deposit, lessen the volume of cast, and decrease the difficulties of river closure.更多还原