grusfyllning

Grusfyllning, or gravel fill, is a layer or volume of gravel or crushed rock used to fill voids, trenches or foundations in civil engineering and building projects. It is chosen primarily for its drainage properties and load-bearing capacity, and serves to create a stable base, distribute loads, and promote drainage beneath structures or surfaces.

Materials used for grusfyllning are typically washed gravel or crushed stone with a coarse grain size distribution and a low content of fines. The exact specification depends on the application, but high permeability and low plasticity are common requirements to minimize pore-water pressures and frost-related issues. Drainage-focused gravels often contain limited fines to preserve permeability, and may range in particle size from several millimeters up to a few tens of millimeters. A geotextile separator is sometimes placed between grusfyllning and the underlying soil to prevent mixing and to improve drainage performance.

Construction and installation generally involve placing the material in lifts or layers and compacting to a defined density when required for structural support. For drainage applications, compaction is often limited to preserve pore space and drainage capacity. The surrounding design may specify moisture content or in-situ density targets. Where the grusfyllning interfaces with different soils, appropriate stabilization or separation measures are used to avoid contamination of the fill material.

Common uses include backfilling around foundations and retaining walls, filling beneath slabs or slabs-on-grade, backfilling trenches for pipes and cables, and creating drainage layers in roads, landscapes, or other substructures. Grusfyllning is chosen for its combination of stability and permeability, contributing to long-term performance of the engineered system.