An interlocking concrete paver is a pre-cast piece of concrete or brick commonly used in exterior hardscaping applications. Developed in Europe and introduced into the United States in the early 1970s.
Interlocking paving stones are installed over a compacted stone sub-base and a leveling bed of sand, concrete paving stones can be used for walkways, patios, pool decks and driveways and airport or loading docks.
Instead of connecting the pavers by pouring grout between the joints, as one would with tiles, sand particles are spread over the pavers and tamped down. The sand of choice today is a polymeric sand that is designed to form into a flexible gel when wet, therefore providing an effective method of locking in pavers, controlling weeds and preventing wash out and cracking.
The mere special tools needed for installing interlocking pavers are vibrating compaction machine or "Vibra Plate" and Shear Cutter. The former is used to compact the base material to 90% density minimum and also to set and interlock the pavers into the sand bed.
The latter is used to cut the pieces to fit at corners and edges. The sand does not easily wash out with rain or garden hose water and a sealant can be spread on to further lock the sand.