CAISSON PREFABRICATED MANHOLE AND EXECUTION METHOD THEREOF

PROBLEM TO BE SOLVED: To provide a caisson prefabricated manhole and an execution method thereof, in which a bottom plate block can be fixed easily, surely and firmly and a construction period is shortened while construction cost can be reduced and which can be executed even at the place of spring water. SOLUTION: In the caisson prefabricated manhole, at least one cylindrical block 4 is placed on the top face of a cylindrical cutting-edge block 1 and connected and fixed integrally with the cutting-edge block 1, a bottom plate block 12 having an inclined plane, in which a peripheral surface is expanded downwards, is inserted into the lower section of the cutting-edge block 1, and waterproofing is executed to a wedge-shaped opening section 21 formed by the periphery of the bottom plate block 12 and the lower inner circumferential surface of the cutting-edge block 1. Connecting fittings 22 consisting of an angle material are placed on the periphery of the top face of the bottom plate block 12, and bolts 26, 26, 27 screwed to buried metal fittings 2, 15 buried to the bottom plate block 12 and the cutting-edge block 1 are inserted from the bolt inserting holes 25a, 25a, 24a of the perpendicular planes 25 and horizontal planes 24 of the connecting fittings 22 and the bottom plate block 12 is fixed.