CONCRETE FILLED STEEL TUBE WITH IMPROVED HEAT RESISTING CHARACTERISTICS AND DURABILITY

摘要

The present invention relates to a steel pipe and, more specifically, relates to a concrete-filled steel pipe. According to the embodiments of the present invention, the concrete-filled steel pipe comprises: an outer steel pipe filled with concrete; and one or more reinforcing beams arranged on an outer steel pipe in a longitudinal direction of the outer steel pipe, wherein the reinforcing beams have a shape of a curved cross section. According to the present invention, the concrete-filled steel pipe is reinforced by the curved reinforcing beam placed inside the concrete-filled steel pipe; thus the concrete-filled steel pipe improves fireproof performance by delaying a sudden contraction in a fire without an additional fireproofing protection.