Delamination is a failure mode that can occur in layered materials. With respect to roads it refers to the loss of large discrete area of the wearing course layer, usually in conjunction with a clear delineation of the wearing course from the layer below.
- Inadequate cleaning or inadequate tack coat before placement of upper layers.
- Seepage of water through asphalt resulting in the breaking of the bond between the surface and the layer below.
- A weak loose layer immediately under the wearing surface.
- Adhesion of surface binder to the tyres of vehicles