PACKED STEEL PIPE CONCRETE STRUCTURE COLUMN

PROBLEM TO BE SOLVED: To support loads well in a fire so as to reduce or eliminate a fire resistant cover by providing a diaphragm arranged at each junctions of joists with threaded reinforcing bars extending along the direction of the axis of a steel-pipe concrete structure column, the diaphragm being placed at each beam junction. SOLUTION: A plurality of threaded reinforcing bars 4 are arranged vertically and secured to a diaphragm 7 by nuts 9. The threaded reinforcing bars 4 are connected together by couplers 10 and are arranged continuously along the direction of the axis of a steel pipe 2. In each of diaphragms 7 placed at two of upper and lower places at each junction 6, four through holes 8 are formed. Concrete 3 is placed and packed ion the steel pipe 3 to construct a concrete structure column 1. No threaded reinforcing bars 4 may be placed between the diaphragm 7 above the junction 6 and the diaphragm 7 below the junction 6. Thus even in the event of a fire while no fire resistant cover exists, cracking and the width of a crack can be reduced. Therefore, either the fire resistant cover can be reduced or no fire resistant cover is required.