摘要：粒径计系清水沉降，由于试样的整体作用．颗粒的沉速值偏大。根据实测的粒径各分级泥沙的流速值，和相应泥沙粒径的标准值，并分别计算出Ｓａ、Φ．建立两者的关系式，则可以此进行粒径计泥沙粒径和沉速间的准确换算。

关键词：颗分方法;泥沙粒径

Abstract:The sizemeter is based on the sinking principle in still clearwater， but the settling velocity of the grain is greater than that of entirety action. Inthispaper，based on the fall velocity of each grading fraction measured with sizemeter and on the standard value of equivalent size diameter， the Sa and Φ can be calculated respectively and their relations can be set up，and then the accurate conversions between thegrain diameter and the fall velocity measured with sizemeter can be carriedon.

Keywords: Sizemeter，Grain-size