Design and Construction of Concrete-Filled Steel Tube Column System in Japan

Abstract

The concrete-filled steel tube (CFT) column system has many advantages compared with the ordinary steel or the reinforced concrete system. One of the main advantages is the interaction between the steel tube and concrete: local buckling of the steel tube is delayed by the restraint of the concrete, and the strength of concrete is increased by the confining effect of the steel tube. Extensive research work has been done in Japan in the last 15 years, including the “New Urban Housing Project” and the “US-Japan Cooperative Earthquake Research Program,” in addition to the work done by individual universities and industries that presented at the annual meeting of the Architectural Institute of Japan (AIJ). This paper introduces the structural system and discusses advantages, research findings, and recent construction trends of the CFT column system in Japan. The paper also describes design recommendations for the design of compression members, beam-columns, and beam-to-column connections in the CFT column system.