Evaluation Method of Deformation Capacity Considering Pullout of steel tube from the member joints for Concrete Filled Steel Tubular Columns with Square Section

Abstract

There has been increasing needs for applying concrete filled steel tube columns with square section (square CFT columns) in railway structures. However, the evaluation method of bending and deformation capacity of square CFT columns has not been established in the design standard. Therefore, to figure out mechanical properties of square CFT columns, we carried out cyclic loading tests, focusing on width-thickness ratio, shear-span ratio, axial force ratio and material strength. As a result, we have proposed an evaluation method of bending and deformation capacity considering pullout of steel tube from the member joints.