PURPOSE: To facilitate construction and prevent breakage by injecting and filling room-temperature setting polymer solution in pores of a structural body having the continuous pores constructed on a foundation, and curing the polymer solution to harden it.

CONSTITUTION: Primer 2 is applied on an asphalt-paved foundation 1, and a primer process is applied. A structural body 3 having continuous pores comprising lamination of nonwoven fabric is constructed on the foundation 1 through the layer of the primer 2. Room-temperature setting polymer solution 6 is then injected and filled in the continuous pores in the structural body 3, and it is cured and hardened. In spite of using the liquid of the polymer solution, occurrence of dropping phenomenon of the material during construction can be prevented.