PURPOSE: To enable execution of a work with high efficiency without leaving an unprocessed part throughout a wide concrete surface by a method wherein a guide part is set in a state to be inclined based on a direction extending perpendicularly to the running direction of a car body and a high pressure water injection part is reciprocatively moved.
CONSTITUTION: A guide part 33 to laterally reciprocatively move a high pressure water injecting part 31 is set in a state to be inclined based on a direction extending at right angles with a running direction B of a running body 11. A green cutting work is effected in a way that the car body 11 is run as the injecting part 31 is moved from the end part, on the side separated away from the car body 11, of the guide part 33 toward the end, on the side approaching the car body, of the guide part. When the injecting part 31 is moved to the end part of the guide part 33, the guide part 33 is re-set such that the end part where the injecting part 31 is positioned is the side separated away from the car body. Consecutively, the green cutting work is continued in a way that the car body 11 is run as the injecting part 31 is moved toward the end part on the side approaching the car body. Further, the above works are repeatedly executed.
HASHIMOTO SATOSHI
OUCHI SADAMICHI
OTA HIROMICHI
SHIBUYA MITSUO
ASANUMA RENKI
