To bury an induction cable inducting a vehicle in a road surface with high precision without requiring skill while ensuring satisfactory appearance.
An asphalt 12 is spread on a crushed stone layer 20 spread on the ground G to form a lower asphalt layer 21. A ditch part 23 is formed along a running path of a vehicle in the lower asphalt layer 21. Powder mortar 25 is charged into the ditch part 23 and is spread uniformly by a uniform spreading jig, and then water is sprayed to harden it so as to form a bottom part 23a of the ditch part 23. An induction cable 4 is arranged on the bottom part 23a of the ditch part 23, and mortar 14 is filled into the ditch part 23. The asphalt 12 is spread on a top face of the lower asphalt layer 21 to cover an upper part of the ditch part 23 in order to form an upper asphalt layer 22.
SHIRAI YOSHIO
KACHI YOSHIO
NIPPON HODO