jordmasse

Jordmassa, in Swedish, literally means soil mass. In geology and geotechnical engineering, it refers to the mass of earth material that makes up the ground at a location. It encompasses mineral particles (such as sand, silt, clay, and gravel), organic matter, water, air, and the structures formed by natural processes and human activity, including compaction and cementation.

The properties of jordmassa determine how it behaves under loads, moisture changes, and environmental conditions. Important properties include dry or bulk density, porosity, water content, grain size distribution, moisture state, shear strength (cohesion and internal friction angle), compressibility, and permeability. Soils are typically classified by particle size into gravel, sand, silt, and clay, and into cohesive (clay and cohesive silt) versus non-cohesive (sand and gravel) groups.

Assessment of jordmassa relies on sampling and laboratory testing, such as grain-size analysis, Atterberg limits, Proctor compaction, and shear tests, as well as in-situ methods like standard penetration testing (SPT), cone penetration testing (CPT), and vane shear tests. Field observations of groundwater conditions, layering, and compaction further inform evaluation.

Applications of jordmassa span civil engineering and construction, where soil behavior affects foundations, slopes, and earthworks; environmental assessments, which study contaminant transport within the soil mass; and agriculture, which considers soil structure and moisture-holding capacity. Management practices include excavation, stabilization, drainage, and grading, with attention to erosion control and long-term stability.

Note: The term is primarily used in Swedish-language contexts; in international geotechnics it is commonly translated as “soil mass” or simply “soil.”