Kieshaltigen

Kieshaltigen describes soils or sediments that contain a substantial proportion of gravel-sized particles. In geology and soil science, Kies (gravel) includes coarse particles roughly between 2 millimeters and 63 millimeters in diameter. A material is described as kieshaltig when these gravel grains constitute a significant share of the total mass, with the remainder formed by finer fractions such as sand, silt, and clay. The threshold is not fixed; in practice, the descriptor is used when the gravel fraction noticeably influences texture and properties.

Kieshaltige materials occur in various environments, particularly in alluvial and fluvial deposits, glaciofluvial outwash, and river or glacial terraces. They may also occur as lens-rich layers within loamy or sandy sediments. The presence of gravel affects physical properties: permeability and drainage are typically higher than in finer-textured soils, while cohesion and plasticity are reduced. Such materials may show high bearing capacity but limited cohesion, influencing compaction behavior and suitability for foundations or roadbeds. Drainage layers and ballast are common engineering uses.

Assessment of Kieshaltigkeit relies on granulometric analysis, often by sieving, to determine the share of gravel in the dry sample. The gravel fraction is commonly reported as a percentage of total mass and guides material selection, compaction requirements, and hydrological modeling.