Dry Sieve Analysis is a foundational laboratory procedure used to determine the particle size distribution of coarse soils, such as sand and gravel. By passing dried soil through a stack of standardized sieves, we quantify the gradation of the material, providing a direct measurement of structural suitability.
Test Objectives
- Determine the gradation of gravel and sand particles
- Classify soil according to engineering standards (USCS/AASHTO)
- Provide data for foundation and soil improvement works
Site Application
- Evaluates grading for drainage and compaction stability
- Assesses suitability for pavement and embankment layers
- Informs the selection of ground enhancement methods
Construction Value
- Ensures correct classification for structural safety
- Prevents settlement caused by poorly graded fills
- Supports precision design of foundation systems
Gradation Parameters
- Percentage of material retained vs. passing
- Coefficient of Uniformity ($C_u$)
- Coefficient of Curvature ($C_c$)
The test involves oven-drying a representative soil sample to remove all moisture, followed by mechanical agitation through a "nest" of sieves. The sieves are arranged with the largest openings at the top and decreasing mesh sizes toward the bottom.
By weighing the material retained on each sieve, we create a Grain Size Distribution Curve. A "well-graded" soil contains a diverse range of particle sizes that interlock effectively, providing superior structural support compared to "poorly-graded" or "uniform" soils.
Our Methodology
- 1 Oven-drying soil to ensure consistent particle separation
- 2 Systematic sieving through calibrated mesh stacks
- 3 Precision recording of retained mass per layer
- 4 Generation of gradation curves and technical reports