CONNECTING STRUCTURE BETWEEN CFT COLUMN AND RC SLAB REINFORCED BY HIGH STRENGTH CONCRETE

摘要

A joint structure between a CFT(concrete filled steel tube) column and a RC(reinforced concrete) flat plate with a compression zone reinforced by high-strength concrete is provided to transfer shear force by load added on a slab to a CFT column between a CFT column and a RC flat plate and to secure sufficient stability against punching shear. The invention relates to a joint structure between a CFT(concrete filled steel tube) column(10) composed of a steel pipe having a hollow and filled with concrete(1) in the hollow and a RC(reinforced concrete) flat plate(100) composed of a reinforced concrete slab, wherein a compression zone(200) on a joint between the CFT column and the RC flat plate is made of high strength concrete having the larger strength(42Mpa~80Mpa) than the strength of ordinary concrete on another zone of the RC flat plate to increase punching shear strength, deformation capacity and energy absorption capacity. In addition, a shear head(20) composed of a steel beam is installed on the side of the CFT column integrally to be buried under the RC flat plate on a joint between the CFT column and the RC flat plate to push out the dangerous cross section of punching shear, thereby to increase stability against the punching shear, and a horizontal support member(30) composed of a beam is connected between shear heads of the adjacent CFT columns to support each CFT column, thereby to secure stability of the CFT column while erecting a CFT column or performing successive construction and to function as a suspension member when punching shear failure occurs on the RC flat plate, thereby to prevent the chain breakdown of buildings.