Axial capacity of rectangular concrete-filled steel tube columns – DOE approach

Zhang

Journal of Constructional Steel Research

et al. 2017

An experimental programme was conducted to investigate the compressive behaviour of concrete-filled cold-formed steel tubular (CFCFST) stub columns with thicker tubes. A total of 30 CFCFST stub columns were tested. The cold-formed square hollow section (SHS) tubes included unstiffened sections and longitudinally inner-stiffened sections using different stiffening methods. Two tubular thicknesses of 6mm and 10mm were considered. The overall nominal dimension of the steel section was 200×200mm, and the length of the stub columns was 600mm. Normal concrete and self-consolidating concrete with a nominal compressive strength of 30MPa were used to fill the cold-formed SHS steel tubes. The effects of the stiffeners on the rigidity, ductility, failure mode and average sectional strength of the CFCFST specimens were examined. The measured strengths of the CFCFST specimens were also compared with the predicted capacities using methods in various codes including AISC, BS5400, EC4, and DBJ and from a finite element (FE) analysis. Results demonstrate that the inner stiffeners affect the deformability, failure mode and overall strength of the stub columns with the 6mm-thick tubes more significantly. The DBJ code method is comparatively the best in predicting the strength capacity. Using the validated FE model, an extended analysis has been conducted and this has provided further insight into the mechanical behavior of the CFCFST specimens.

Section: Introductionmentioning

confidence: 99%

Experimental study of concrete filled cold-formed steel tubular stub columns

Zhang

Journal of Constructional Steel Research

et al. 2017

Magazine of Concrete Research

“…In research into the behaviour and performance of steel tube columns, Chitawadagi et al (2010aChitawadagi et al ( , 2010b utilised a linear regression model to study the effects of cross-section dimensions of columns of a given length. Simplified expressions were proposed to predict the ultimate load-carrying capacity of short columns, which covers columns with a D/t ratio of 22·3-50·8 and L/D ratio of 7·8-22·5.…”

Section: Load-strain Relationshipmentioning

confidence: 99%

“…Composite construction encompassing the use of steel and concrete has been widely utilised in structural engineering, and steel tube columns filled with normal concrete have increasingly found applications in high-rise buildings, offshore structures, bridges and warehouses, particularly in regions with a high risk of seismic loading (Karimi et al, 2011;Wu et al, 2013). Through experimental work, theoretical approaches and finite-element analysis, many studies have been conducted to investigate the effects of steel tube cross-section shape , concrete strength Giakoumelis and Lam, 2004;Liang and Fragomeni, 2009;Yong and Ellobody, 2006), depth-to-thickness ratio (Chitawadagi and Narasimhan, 2009;Chitawadagi et al, 2010a;Gupta et al, 2007) and loading conditions (Song et al, 2010;Yu et al, 2007) on the failure mode, load-carrying capacity and ductility of concrete-filled steel tube columns.…”

Section: Introductionmentioning

confidence: 98%

Material and structural response of steel tube confined recycled earthquake waste concrete subjected to axial compression

Dong¹,

Wang²,

Guan³

2016

This paper reports on an experimental study of the mechanical properties of recycled aggregate concrete (RAC) and the structural behaviour of steel tube columns filled with RAC subjected to axial compressive loading. A total of ten specimens were tested to investigate the influence of the steel tube configuration (circular or square), the type of concrete (normal concrete or RAC) and the proportion of recycled coarse aggregate (RCA) used in the RAC. The mechanical properties of RAC and RAC columns confined by steel tubes were studied for RCA replacement ratios of 0, 25, 50, 75 and 100%. The results show that RAC may give a slightly lower strength during the first 28 d of curing.However, the ultimate strength (90 d curing) of steel tubes filled with RAC was slightly higher than those filled with normal concrete. The load-carrying capacity of circular steel tube columns filled with RAC was found to be higher than that of square section tubes. Theoretical calculations of the load-carrying capacity of the concrete-filled steel tube columns are presented and compared with experimental results.

Construction and Building Materials

“…However, square and rectangular CFT columns are still increasingly used in civil engineering due to easier construction in beam-to-column connection, high cross-sectional bending stiffness and aesthetic reasons [32]. A lot of researches have been carried out on the behavior of square CFT columns under axial compression [33], [34], [35], [36] or bending load [37], [38], [39], [40]. Inspired by the idea of circular CFT columns, the authors innovatively proposed a new type of structural member termed circular ice filled steel tubular (IFT) column in which the concrete was replaced by ice [41].…”

Section: Introductionmentioning

confidence: 99%

Axial compressive behavior of square ice filled steel tubular stub columns

Wang

Chen

Wan

et al. 2018

Square IFT column is proposed to combine the advantages of ice and steel tube. • Influence of width-to-thickness ratio of steel tubes on square IFT is analyzed. • Bearing capacity of IFT increases with the decrease of width-to-thickness ratio. • Good composite action between outer steel tube and ice core is achieved. • Equations for predicting bearing capacity of square IFT columns are proposed.