marks as an unknown form of mechanical markers, such as ground-in strips, or strange road surface markings. In some cases, these marks are confusing for motorists. When roads are under construction and lanes are laterally shifted, such marks may interfere with temporary lane markings. As the marks from the dowel bar retrofit are not intended to be any form of road surface markings, the responsible agencies try to make these marks smooth and hope to make them less visible to the motorists. See also Concrete grinder References External links California Route 8 Wisconsin International Grooving & Grinding Association Pavement engineering