Siefanalyse

Siefanalyse, commonly referred to as sieve analysis or gradation analysis, is a method for determining the particle size distribution of granular materials. It involves separating a sample through a stack of sieves with progressively smaller openings and measuring the mass retained on each sieve.

Equipment and standards typically include a set of test sieves (in a standard series with defined openings), a sieve shaker, a receiving pan, and a balance. For some materials, wet sieving may be used to prevent agglomeration or loss of fines. Standards such as ASTM E11 (for sieve hardware) and related national or regional specifications govern procedures and sieve sizes.

Procedure generally starts with sample preparation: drying to a constant mass, breaking any lumps, and ensuring representative sub-sampling. A known mass of the sample is placed on the top sieve of the stack, which is then shaken for a prescribed time. After shaking, each sieve is weighed to determine the mass retained, and the pan is weighed for material that passes through the smallest sieve. Percent retained on each sieve is calculated, and percent passing is obtained by subtraction from 100%.

Data interpretation involves constructing a particle size distribution curve from the retained and passing fractions. Key descriptors include D10, D50 (the median particle size), and D90. Relative measures such as the coefficient of uniformity Cu = D60/D10 and the coefficient of curvature Cc = (D30)^2/(D10·D60) are used to summarize the distribution, particularly for quality control in aggregates and soils.

Applications span construction materials, soils classification, mining and pharmaceuticals. Limitations include reduced effectiveness for cohesive or ultra-fine materials and the need for careful sample preparation and drying to ensure reproducibility.