PURPOSE: To prevent swelling even on being exposed, withstand heavy loads, and make it hard to transfer the effect of cracks in the substrate to the upper layer, by constituting a water proof layer made of reinforced plastic mold plate or the like as arm exposed water proof structure.
CONSTITUTION: An adhesive 2 like urethane is applied on the whole face of concrete substrate material 4 smoothly finished and reinforced plastic mold plates like FRP plates 1 are butt-jointed with each other to lay down. In this case, the plastic mold plates with a large elastic strength and a linear expansion coefficient ranging 2.0×10-5±10% so as to restrain from inducing cracks in the water proof layer resulting from the cracks in the substrate. The plastic mold plate is stuck so as not to peel off even when a heavy load like an automobile acts thereon. But in order to prevent warps brought at the ends, pins 6 for concrete are driven around the area. Finally after the surface is made coarse, synthetic resin 5 as the top coat including mineral particles is applied on the whole face with the connection joints 3 to become even in the thickness.
SATO MASAO
YAMAGUCHI KEIZO
