AN INNOVATIVE DESIGN FOR PAVING USING VERTICALLY- INTERLOCKING ARTICULATED CONCRETE MATS

SUMMARY Paving mat systems using cast concrete block held together with embedded wire rope or cable have found wide use in erosion control, and paving fords, boat ramps and low-volume roads. Cable-linked paver blocks have the advantage of being less subject to displacement than separated pavers. They are less subject to washout, are difficult to vandalize and are not lifted by tracked vehicles. Their disadvantage has always been that the sections of the mats have to be connected to be effective. This requires that U-bolts or wire splices be installed between mat sections. The bolts and splices have to be unbolted or cut to move the mat sections. A new design of vertically-interlocking paving mats has been developed to overcome the problems of placing and removing connections between mat sections. This makes a paving system that is easily placed and easily lifted and moved. Also, since this new paving system consists of two distinct layers of blocks, each upper block rests on parts of four blocks below it; so the load on the upper block is effectively distributed over four lower blocks. The lower ground pressure makes the paving system useful where the sub grade soils are not ideal. The upper layer of block is staggered so the openings from the top of the upper block to the ground are smaller and the problem of vegetation growing up between the blocks is reduced. The complete system consists of two layers of paver mats. Each layer of mat consists of concrete pavers cast on a grid of intersecting cables that hold the pavers together. The shape used for the block is the key to interlocking the mats vertically. In the casting process, one vertical half of the block is formed as a square paver (the square side); but the lower vertical half of the block is formed as a square rotated 90-degrees (the diamond side) and dimensioned so that the corners of the square are at the mid-point of the sides of the upper square side. When the mat is laid down with the square side on the ground surface, the diamond side has spaces between the diamonds that are sized to allow another mat layer to be placed diamond side-down with the diamonds from the upper mat fitting between the diamonds on the lower mat. The exposed top of the twolayer mat consists of the square-faced side of the pavers. One three-paver by three-paver mat section can be laid down over the intersection of four similar mats below it to lock them together. Under normal circumstances the weight of the upper mat will guarantee that the lower mats remain locked together until the upper mat is lifted off.