ANALYSIS OF SQUARE CONCRETE-FILLED COLD-FORMED STEEL TUBULAR COLUMNS UNDER AXIAL CYCLIC LOADING

Abstract

This research studied the behavior of the square concrete-filled cold-formed steel tube (CFST)
columns under axial cyclic loading. A total of 9 specimens were tested. All tested specimens are 75×75
millimeter square tube section. The parameters varied in the test are the thickness of steel tube, the compressive
strength of filled concrete, and specimen length. The values of tube thickness are 1.8 and 3 millimeters. The
column lengths are 500 and 1000 millimeters. In-filled concrete compressive strengths are 0 (unfilled), 20 and
40 MPa, respectively. Then the experimental strengths were compared with the design strengths computed
from various international design codes. Finally, the specimens were analyzed by finite element software. The

analytical results showed fairly close agreement with experimental results in terms of buckling mode, load-
deformation response, the tension capacity and the decreasing compression capacity under cyclic load.