Avrettingslagets

Avrettingslagets, or avrettingslaget in its base form, refers to a leveling layer used in civil engineering to create a flat, even surface on top of a subbase or subgrade before laying the wearing course such as asphalt or concrete. Its primary purpose is to smooth out small-scale irregularities, ensure uniform thickness, and provide a stable foundation for subsequent pavement or floor layers. The avrettingslag can be constructed from a variety of materials and bound with different technologies, depending on climate, traffic, and design requirements.

Common material options include granular sands or fine gravels that are compacted to a target density, cement-stabilized lean concrete, hydraulically bound layers, or, in some cases, asphalt-bound leveling layers. The choice of material and binding method affects drainage, frost resistance, and the longevity of the final surface.

Construction typically involves preparing the underlying surface, spreading the leveling material to the specified thickness, and compacting with rollers or other compaction equipment. The surface is finished to a smooth profile to facilitate the subsequent wearing course. Quality control measures monitor thickness, density, surface regularity, and moisture content where applicable.

Role and significance: a well-designed avrettingslaget contributes to even load distribution, reduces the risk of surface deformations and cracking in the final pavement, and supports ride quality and durability. Standards and specifications for avrettingslaget vary by country and project, but the underlying principles emphasize flatness, support, and proper integration with the following layers.

See also: Pavement engineering, Subbase, Wearing course.