CONCRETE FILLED STEEL PIPE COLUMN REINFORCED BY REINFORCING BARS AND HAVING FIRE RESISTANCE AND CONCRETE FILLED DOUBLE STEEL PIPE COLUMN

摘要

PROBLEM TO BE SOLVED: To provide a concrete filled steel pipe column reinforced by reinforcing bars having excellent fire resistance performance and allowing safe and proper arrangement of a main bar and a hoop bar based on the comprehensive evaluation of a cross section and arrangement of each member constituting the concrete filled steel pipe column reinforced by reinforcing bars and the relation between the strength and a performance in a predetermined period of fire resistance time. SOLUTION: In this concrete filled steel pipe column 1 reinforced by reinforcing bars, the main bar 4 and the hoop bar 5 are arranged so that an axial force acting on the column is below the total of an axial force burdening force Nc of the concrete filled steel pipe column except the main bar and the hoop bar in a predetermined period of fire resistance time, an axial force burdening force Ns of the main bar 4 in the predetermined period of fire resistance time, and an axial force burdening force Nf of the hoop bar 5 in the predetermined period of fire resistance time.