2019 CSCE Annual Conference - Laval (Greater Montreal)

2019 CSCE Annual Conference - Laval (Greater Montreal) Conference

Numerical investigation of concrete-filled steel square columns subjected to concentric and eccentric loading

Mr. Soebur Raham, Military Institute of Science and Technology
Mr. Kamrul Islam, Ecole Polytechnique de Montreal (Presenter)
Mr. Ibriju Ibrahim, Military Institute of Science and Technology
Dr. Aziz Ahmed, University of Wollongong

Concrete filled steel tubular (CFST) column is a type of composite column where the concrete core is fully encased by steel section of different shapes. CFST column has garnered popularity due to its beneficial mechanical properties such as high strength, stiffness and ductility. In addition, CFST column enhances the overall rigidity of the structure and provides significant shear resistance to strong earthquakes and other lateral loads. This paper presents the details of an experimental investigation on fifteen CFST stub columns made with built-up section. The test specimens were fabricated by metal arc welding from hot-rolled channel section of nominal thickness 4 mm and 5 mm.  All the fifteen stub columns were tested in pure axial compression.  Moreover, four hollow stub columns with two different sizes were tested.  The variable parameters for the experiment were concrete strength, cross sectional dimension and thickness of the steel section. Three different concrete strength, 30 MPa, 40 MPa and 50 MPa were used in this study. Both tensile and compressive material properties were obtained by means of coupon tests and concrete cylinder tests. The main objective of this research work is to study the behavior and the cross-sectional capacity of CFST stub columns made with built-up sections. The failure modes and load–end shortening behavior of the CFST columns were investigated. The experimental results were compared with the existing AISC-2013 and EC4 design guideline which clearly show the conservative nature of code predictions.  The experimental investigation was complemented by finite element (FE) modelling using ABAQUS. Numerical models were validated using the current experimental data and the available test results in the literature. The FE models predicted the experimental load-deformation curve, ultimate strength and failure modes with good accuracy.