为研究水库泥沙淤积与泥沙密度之间的变化关系，采用丹江口水库不同库段、不同粒径的泥沙，进行了不同管径、不同深度和分别加沙的沉降实验，发现了一些特殊的现象。并对这些实验数据和丹江口水库的实测资料，进行了分析。研究结果说明泥沙沉降快慢与泥沙表层水深无关，而泥沙的密度是随泥沙沉降快慢而变的。

In order to study the relation between the settling velocity of sediment and the change of sediment bulk density in Danjiangkou Reservoir, and adopting the various sediment particle sizes taken on from different reservoir segments, the sediment settlement experiments were carried out under the conditions of different pipe diameters, different water depths, and sands adding respectively. During the experiments we found many especial phenomena. By comparing and analyzing the experimental data and the measured data, the results show that the velocity of sediment deposition is independent of the surface layer water depth, but the sediment bulk density changes with the velocity of sediment deposition.