interlocking pavers paving block patio pavers INTERLOCKING PAVERS UNILOCK interlocking pavers are generally composed of a surface consisting of precast modular concrete units of varying shapes, colours and texture, placed over a graded sand base and interlocked with bedding and joint sand, which can be constructed over a variety of subbases. The concept dates back to the roads of the Roman Empire, and was refined after the Second World War in Europe. The modern concept of high quality, precision manufactured concrete pavers has resulted in the construction of millions of square metres of interlocking pavers constructed each year in Europe, and an expanding market in North America. Due to the segmental nature of the pavement, concrete interlocking pavers can articulate under applied loads, much like flexible pavements. Unlike flexible pavements, the interlocking nature of the pavements increases significantly under traffic. Conventional flexible pavement design and construction methods have been easily adapted to the concept of concrete interlocking pavers.