Overview
EN ISO 17892-1:2014 - "Geotechnical investigation and testing - Laboratory testing of soil - Part 1: Determination of water content" specifies the established laboratory oven‑drying method for determining the water (moisture) content of soil specimens. The standard is applicable to geotechnical investigations where water content is used for soil classification, control of re‑compacted fills and as a required input for most field and laboratory tests. The method measures mass loss on drying to a constant mass and expresses water content as the ratio of free water mass to dry soil mass.
Key topics and technical requirements
- Scope & purpose: Definitive laboratory method for water content determination in geotechnical contexts; supports EN 1997‑1 and EN 1997‑2 requirements.
- Principle: Determine mass loss after oven‑drying to constant mass; mass loss attributed to free water and referenced to remaining dry solids.
- Equipment requirements:
- Forced‑draft drying oven with uniform temperature control.
- Thermometer/thermocouple accurate to ±1 °C.
- Balance accurate to 0.01 g or 0.1% of sample mass (whichever is greater).
- Suitable containers (glass, porcelain or corrosion‑resistant metal) and optional desiccator.
- Test specimen preparation: Guidance on storage (airtight, 3–30 °C, protected from sunlight/heat), representative sampling and minimum specimen masses (examples from Table 1):
- Dmax ≤ 0.063 mm → recommended ≥ 30 g
- Dmax ≤ 2.0 mm → recommended ≥ 100 g
- Dmax ≤ 10.0 mm → recommended ≥ 500 g
- Dmax ≤ 31.5 mm → recommended ≥ 3 000 g
- Dmax ≤ 63.0 mm → recommended ≥ 21 000 g
(Smaller specimen masses may be used with reporting caveats.)
- Procedure elements: Specimen selection, drying to constant mass, checks, reporting of results and equipment calibration/maintenance (Annex A).
Practical applications
- Soil classification and indexing (laboratory and field correlation).
- Quality control for compaction and re‑compacted soil works.
- Input parameter for geotechnical design tests (e.g., Atterberg limits, density, permeability).
- Routine laboratory testing in site investigation programs for foundations, earthworks, tunnels and excavations.
Who should use this standard
- Geotechnical engineers and consultants
- Soil testing and materials laboratories (QA/QC)
- Construction contractors and site engineers involved in compaction control
- Research institutions and university labs performing soil property characterization
Related standards
- Other parts of the ISO 17892 series (Parts 2–12) covering bulk density, particle density, particle size distribution, oedometer, triaxial, shear tests, permeability, Atterberg limits, etc.
- ISO 14688‑1 (soil identification/description) and ISO 386 (laboratory thermometers) are normatively referenced.
Keywords: EN ISO 17892-1:2014, water content, moisture content, oven‑drying method, geotechnical testing, soil laboratory testing, soil classification.