To prevent the inclination, movement, overturning, etc., by providing a first receiving groove part and a screw receiving part on a support post erected on a bottom plate, and providing a level regulating screw which is screwed into a second receiving groove part and the screw receiving part of the support post on a trestle plate fitted to the support post.

A lower end main reinforcement and a lower end distributing reinforcement are dropped from an upper part of a support post 3 along a guide part 3, and received by a first receiving groove part 3a. A trestle plate 4 is fitted to the support post 3, an upper end distributing reinforcement is dropped onto and received by a second receiving groove part 4a, and an upper end main reinforcement is loaded on the upper end distributing reinforcement to tighten the intersection by the binding wire. A level regulation screw 5 is screwed into a screw receiving part 3d of the support post 3 after the slab reinforcement arrangement, and the height of a receiving plate 5a is regulated by changing the screw-in quantity. Thus, setting of a spacer, or inclination, movement, overturning, etc., due to the biting of one part are not generated.