On the choice of appropriate sieves and diffusor sieves for air pluviation based on sand grain properties
On the choice of appropriate sieves and diffusor sieves for air pluviation based on sand grain properties
Air pluviation is a widely used method in geotechnics for creating sand samples for physical modelling purposes. The benefit of this method is the wide range of possible bulk densities to be reached and, with the right equipment settings, homogenous samples. This leads to high quality experimental results.
However, to be able to achieve homogeneity, the set-up of the pluviation stand needs to be chosen carefully. Here, especially the sieve together with the diffusor sieves play an important role. The sieve is responsible for adjusting deposition intensity, which describes the mass of sediment per area and time falling on the sample surface. The diffusor sieves, which usually consist of a relatively coarse quadratic mesh, are generally attached below the sieve to uniformly distribute the sediment over the sample surface. If either the diffusor sieves or the sieves are not adjusted to the used sand, considering grain size as well as other grain properties, the resulting sample will not be homogenous.
To investigate this effect, an existing pluviation test stand is used for varying diffusor sieves and sieves, as well as the air pluviated sands. The resulting samples are examined regarding their density and grain size distribution by using directly collected sand samples as well as 3D-laser scanning. In addition, the properties of the sand grains, such as grain size distribution, roundness or shape, are determined by dynamic image analysis. From these results, the required geometries for the sieve and diffusor sieves to achieve homogenous samples are determined.
Natascha Heim; Sascha Henke
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Session 1: New facilities, new equipment, and measuring techniques
https://doi.org/10.53243/ICPMG2026-76