with the surface. The required macrotexture of the surface is achieved by wire-
brushing or grooving.
Wire-brushing is done either manually or mechanically from a skewed travel-
ling bridge moving along the line of the pavement. The wire brush is usually a
minimum of 450 mm long. Grooving is done using a vibrating plate moving
across the width of the finished pavement slab forming random grooves. They
have a nominal size of 6 mm by 6 mm, providing excellent surface water drainage
properties. A high level of wet-road skid resistance is obtained by deep groov-
ing, but problems may arise with higher tyre noise.7.8 References,
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