Principle and application
Soil characterization tests classify the soil from its basic properties: moisture content, particle-size distribution, Atterberg limits, unit weight and compaction. They are the starting point of any design, from fill control in earthworks to the subgrade in pavement.
The test in stages
Moisture and unit weight
Determination of the natural moisture content and the unit weight.
Particle-size distribution
Sieving and sedimentation for the grain-size distribution.
Atterberg limits
Liquid and plastic limits for fine-grained soils.
Compaction
Standard/modified Proctor and, on request, CBR and Hilf.
For soil classification
| Particle size | Grain-size distribution curve |
|---|---|
| Atterberg | LL, PL and plasticity index |
| Unit weight | Bulk and specific gravity of grains |
| Compaction | Optimum moisture and maximum density |
Quality and field operation
Data quality
- Calibrated balances, ovens and sieves.
- Procedures to the current testing standards.
- Duplicates and repeatability control.
- Report reviewed before delivery.
Safety and operation
- Qualified for high-compliance areas: mining, industry and ports.
- Organised, signed work front with an HSE procedure in place.
- Own crews and fleet, including night shifts.
The deliverable
| Characterization report | Curves, indices and soil classification |
|---|---|
| Compaction | Proctor curve and parameters |
| CBR/Hilf | When contracted |
| Typical lead time | According to the number of samples |
Sectors and project types
Frequently asked questions about soil characterization
What are soil characterization tests for?
Soil characterization tests classify the soil from its basic properties: moisture content, particle-size distribution, Atterberg limits, unit weight and compaction. They are the starting point of any design, from fill control in earthworks to the subgrade in pavement.
What do the Atterberg limits indicate?
The behaviour of fine-grained soils with moisture: the liquid limit and the plastic limit define the plasticity index, used in classification and in predicting soil behaviour.
What is the compaction test for?
It determines the optimum moisture and the maximum density of the soil, the basis for controlling fills and subgrade in earthworks and pavement.
Fill compaction control in practice
Technical bulletin on compaction tests and field quality control.
Soil characterization for your project
Tell us about your project and we will prepare the investigation plan and the quote.