PURPOSE: To enhance workability by placing the ends of PC beams respectively having a projection on an end all around the heads of PC pillars, coupling an L-shaped fixed type form piece between each beam and filling concrete in a space formed above the heads of the PC pillars with the side of each L-shaped form piece.

CONSTITUTION: The ends of PC beams B are placed around the heads of PC pillars in such a way that the front of a projection 3 will come to the same plane as the external surface of PC pillars A. Then, an L-shaped form piece C fabricated with a steel and the like is coupled between adjacent PC beams B from the upper side of a floor plate with the front of the projection of each PC beam used as a guide. Thereafter, a donut shaped spacer block 5 is fitted to the hoop reinforcement 2 of the PC pillars A and the L-shaped form piece C is clamped with the spacer block 5 in a space between the front of the projection 3 of the PC beams B and the block 5. Furthermore, concrete is filled in a space formed above the heads of the PC pillars A and the execution of a panel zone is thereby completed.