Laying slot units Pfuhler-Schlitzrinnen-System Z Type N

Reinforced concrete slot units are to be laid using suitable lifting gear which allows uniform and precise lifting and lowering (e.g. motorised crane, appropriate excavator). The laying equipment provided, as described under 2, must always be used.

For Class D, the slot units are to be laid in the already prepared mortar bed and vertically aligned using wedges. Complete subsequent grouting under the units is not allowed due to the full surface support required.

Class F channels are to be laid and aligned on appropriate spacers. The resulting gap between the channel element and foundation is to be filled with the grouting mortar described above to ensure full surface support of the channel.

Before joining the elements, the socket and gasket ring must be cleaned and the lubricant supplied must be thickly applied to the sealing surface of the socket. The slot unit suspended from the laying equipment must then be positioned next to the already laid channel until the sealing ring is uniformly covered and the parts must then be pushed together. After joining the channel elements, check that the sealing ring/gasket has not slipped. If it has, separate the channel elements again, pull on the sealing ring so that it sits properly and then rejoint the parts. The alignment of the surfaces can be adjusted by laying wedges under the units if necessary. Ensure that the width of the butt joints is at least 5 mm and maximum 10 mm. To simplify laying, elastomer spacers are attached to the end faces of the spigot end to ensure compliance with this requirement. The channels are to be jointed so that the spacers touch both units. If no spacers are available, the correct butt joint width can be set, e.g. by inserting wooden battens of the correct thickness in the joint on both sides of the socket while pushing the channels together. 

Forces, e.g. due to temperature stresses, may not be transferred to the slot units from the adjacent traffic areas. If these are made from stiff materials, e.g. concrete, this is to be taken into account in the design. Therefore, adequately dimensioned expansion joints (not contraction (dummy) joints) are to be made in the slabs along the reinforced concrete slot units. To enable braking forces to be transferred from the channels into the adjacent members, continuous EPS rigid foam panels EPS EN 13163 CS(10)150 with a maximum width of 8 cm or equivalent must be laid over the whole channel height in the joint between the channel element and the traffic area. These panels must never be allowed to be so highly compressed due to expansion of the adjacent surfacings that they transfer horizontal forces from the pavement onto the channel elements.

After laying and finishing the adjacent areas, all longitudinal and transverse joints must be filled with a joint sealant with general building approval for LAU systems. The relevant installation instructions and conditions of the sealant manufacturer must be noted and followed.

To prevent spalling at the corners and edges, reinforced concrete slot units may not be driven over during construction, before completion of the adjacent traffic areas. If using compacting equipment or pavers, ensure that they are not driven too close to the reinforced concrete slot units.