Depending on the property of the subsoil and loading of the traffic area, the reinforced concrete slot unit is installed on a carefully compacted bed of gravel - sand or crushed rock (frostproof layer) and a blinding layer made from C25/30 concrete (Class D) or on a statically calculated reinforced concrete foundation (Class F). The characteristic values for the formation under the foundation or blinding layer on which the structural calculation is based and, if applicable, the minimum dimensions and minimum reinforcement of the foundation are shown in the typical drawings of the installation and support/bedding of the respective load class. These specifications must always be complied with.
For load class F, the top of the foundation to be built under the channel is to be profiled according to the typical drawing in DIN 1045-1 so that interlocking (keying) results. The profiling must be made perpendicular/crossways to the direction of the linear drainage. Alternatively, the granular structure of the concrete can be exposed on the surface of the foundation. The connection between the channel and foundation is to be made using a grouting mortar or adhesive or hydrophilic (swelling) mortar joint with approval issued by the DIBt Berlin. The mortar joint must at least correspond to the strength property of C 25/30. Attention is to be paid to the mortar's resistance to frost and de-icing salt if subsequent moisture ingress to this joint cannot be prevented.

Reinforced concrete slot unit Class D, installation and support/bedding

Reinforced concrete slot unit Class F, installation and support/bedding