Experimental Investigation on the Axial Compressive Behaviour of Cold-Formed Steel-Concrete Composite Columns Infilled with Various Types of Fibre-Reinforced Concrete

Abstract

The exceptional structural strength and low cost of steel-concrete composite columns make them a popular choice for civil engineering structures. Numerous forms of composite columns, including steel tubes filled with concrete, have been produced recently in response to various construction situations. Cold-formed steel tubular columns with concrete filling have higher strength and ductility due to their capacity to withstand inner buckling and postpone outward buckling. The objective of this research is to determine the ductile and strength performance of composite columns containing various forms of fibre-reinforced concrete when subjected to axial compression. Several different kinds of fibre-reinforced concrete (FRC) are employed as additives in hollow steel columns, including steel FRC, carbon FRC, glass FRC, coir FRC, jute FRC, and sisal FRC. Axial compression tests were performed on 24 columns, including three hollow steel columns and 21 composite columns. Three distinct slenderness ratios were developed and used. Axial bearing capacity, compressive stress-strain curves, ductility, peak strain, axial shortening, and toughness were among the topics covered by the axial compression test. Experimental findings demonstrated that all conventional composite columns experienced failure through overall buckling, Local buckling and crushing of concrete infill, which was transformed into more ductile failure using fibre-reinforced concrete infills. The test results revealed that fibre-reinforced concrete-infilled steel columns outperformed conventional composite columns in terms of strength, ductility, and energy absorption capacity. The percentage increase in load-carrying capacity was observed as 203.88%, 193.48% and 190.03% when compared to hollow cold-formed steel tubular columns in stub, short and medium columns, respectively. Under assessment of stub, short, and medium columns, the load-strain plots demonstrated that the steel fibre-reinforced concrete in-filled columns performed well in terms of ductility. Localized buckling and crushing of the concrete infill caused the composite columns with low slenderness ratios to fail. In contrast, concrete-filled steel tube columns with higher slenderness ratios showed column failure through the overall buckling of the composite column.

Modeling and Calculation of Improved Centrifuged Reinforced Concrete Columns with Variotropic Structure

“…The results obtained in [75,76] are qualitatively and quantitatively similar to the results of this article. As in this article, the nature of the failure under an eccentrically applied load leads to distortion and local buckling of the column.…”

“…These two works agree in an interesting way with our results. For example, the authors of [75] in their work were guided by a recipe-technological method-additional dispersed reinforcement of the column concrete with the help of fiber. Attention is drawn to the constructive solution of the column-this is a steel-concrete version.…”

“…Attention is drawn to the constructive solution of the column-this is a steel-concrete version. Thus, the authors of [75], having applied an integrated design and technological approach, managed to achieve an increase in the bearing capacity of about 200%. In the same article, an effect was revealed that is the release of a hidden resource at a certain eccentricity, which amounted to about 6%.…”

Investigating the Factors Influencing the Strength of Cold-Formed Steel (CFS) Sections

“…Additionally, as f'c increased, the concrete contribution ratio (CCR) tended to increase in value. The increased ductility and strength of CFS tubular columns filled with concrete are a result of their ability to resist interior buckling and delay external buckling [122]. The specimen size has no bearing on the failure mode of square concrete-filled steel tubular (CFST) columns [123].…”

Stability of Steel Columns with Concrete-Filled Thin-Walled Rectangular Profiles

“…At the present time, many numerical and experimental works (Alatshan et al [4], Chepurnenko et al [5], Grzeszykowski and Szmigiera [6], Florence and Senthil [7], Zhen et al [8]) are devoted to the topic of columns having hollow profiles filled with concrete. Storozhenko et al [9] performed experiments on high-strength composite columns subjected to eccentric loading.…”