5.1 Applications
Rigid clay pavements (see Section 2. Definitions) can be utilised in a wide variety of applications including domestic pathways, driveways, patio areas, pedestrian areas and can also be used where heavy traffic loads are expected.

Figure 8  Typical cross section through rigid paving

5.2 Laying
5.2.1 Subgrade
The considerations with regard to the subgrade for a rigid pavement are the same as those for a flexible pavement.

5.2.2 Sub base
The sub base for a rigid pavement is a concrete slab.
The strength, thickness and reinforcement is to be consistent with expected traffic loadings and subgrade strength and designed by the engineer.
The surface is finished smooth and allowed to harden overnight before pavers are laid.

5.2.3 Paver laying
Perimeter pavers are laid first, generally as a header course or double stretcher course around the job. They are bonded to the hardened slab either by a strong cement:sand mix (1:3) or by an adhesive.

Once the perimeter pavers have been installed the main body of the pavement can then be laid in the chosen pattern. Vehicular traffic will require either 45 or 90 degree herringbone pattern.
The gaps that are essential between pavers in a flexible pavement are not necessary in a rigid pavement; however, it is necessary to align joints throughout the scheme to achieve a visually attractive finish.

5.2.4 Expansion joints
Expansion joints must be considered when laying a rigid pavement. The gaps between pavers in a flexible pavement allow for thermal and long-term moisture expansion of clay pavers to be taken up. In rigid paving this does not occur, therefore expansion joints are required.

Figure 9  Rigid paving expansion joint detail

5.2.5 Joint filling
Once all the full and cut pavers are placed it is time to fill the joints. The jointing mix is a 1:3 cement:fine sand mix. This can either be trowelled and pointed traditionally ensuring the joints are completely full, or a fluid slurry can be mixed. This slurry must be sufficiently fine so that it may flow around any gaps in the paver and fill any voids underneath them.

In either method of joint filling, care must be taken to avoid staining of the paver face.
Vehicular traffic should be prevented from traversing the pavement for at least 4-5 days.