Optimizing the Performance of L-Shaped Concrete-Filled Steel Tube Columns Under Eccentric Loading

Document Type : Technical Notes

Authors

1 Associate Professor, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

2 M.Sc. Student, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

3 Assistant Professor, Department of Civil Engineering, Faculty of Civil Engineering and Architecture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

Abstract

Special-Shaped Concrete-Filled Steel Tube (SCFST) columns have a higher bearing capacity, ductility, and energy absorption compared to other columns. Due to their special shape, the columns can be utilized in different parts of the building without protrusion of member. In L-shaped CFST columns, this study investigated the effect of various parameters (such as yield stress of the steel wall, characteristic strength of the concrete, height of the column, thickness of the steel wall, and geometry of the stiffeners) on the eccentric load-bearing capacity. In other words, the bearing capacity has been measured based on the optimal performance of these columns under the effect of axial and eccentric loads. Also, the ratio of load-to-weight (p/w) has been considered. Load-displacement diagrams and the weight of steels used in different columns are compared. Based on the obtained results, the changing of the thickness and strength of the steel wall has a significant effect on increasing the bearing capacity. Whereas, the concrete strength has a lesser impact on the bearing capacity of the columns. The column with greater thickness performs better than the column with less thickness in terms of ductility and energy absorption capacity under eccentric loading.

Keywords


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