TY - JOUR
T1 - Behavior of octagonal concrete-filled double-skin steel tube stub columns under axial compression
AU - Alqawzai, Shagea
AU - Chen, Kang
AU - Shen, Le
AU - Ding, Miao
AU - Yang, Bo
AU - Elchalakani, Mohamed
N1 - Funding Information:
The authors would like to gratefully acknowledge the support of this research provided by graduate scientific research and innovation foundation of Chongqing , China (Grant No. CYB19016 ) and the funding support from the Chongqing Talents Plan for Young Talents (No. CQYC201905055 ).
Funding Information:
The authors would like to gratefully acknowledge the support of this research provided by graduate scientific research and innovation foundation of Chongqing, China (Grant No. CYB19016) and the funding support from the Chongqing Talents Plan for Young Talents (No. CQYC201905055).
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/7
Y1 - 2020/7
N2 - This paper presents an experimental investigation on the behavior of stiffened octagonal concrete-filled double-skin tube (CFDST) stub columns subjected to axial compression. A total of eight specimens were prepared and tested under axial compression aiming to study the effects of longitudinal stiffeners and hollow ratio on the elastic-plastic local buckling and ultimate load-carrying capacity of the test columns. The specimens consist of two control specimens without stiffeners (unstiffened columns) and two specimens stiffened with outer-inner tubes welded stiffeners (O[sbnd]I stiffeners) in four sides of the octagonal steel section. In addition, four specimens were stiffened with two types of stiffeners: O[sbnd]I stiffeners and outer tube welded stiffeners (O stiffeners) in eight sides of the outer steel tube section. Furthermore, two hollow ratios were employed. Based on the test results, the ultimate load-carrying capacity, load-displacement curves, load-strain response, ductility, and failure modes were discussed and clarified. The test results indicated that the strength and ductility of the specimens were improved greatly by the presence of the stiffeners. The stiffeners significantly enhanced the confinement and prevented the occurrence of elastic-plastic local buckling of the outer tube. Besides, current design equations were used to predict the ultimate load-carrying capacity of octagonal CFDST stub columns. The test results were then compared with the predicted ultimate capacities of existing design equations. These predictions showed good agreement with the test results.
AB - This paper presents an experimental investigation on the behavior of stiffened octagonal concrete-filled double-skin tube (CFDST) stub columns subjected to axial compression. A total of eight specimens were prepared and tested under axial compression aiming to study the effects of longitudinal stiffeners and hollow ratio on the elastic-plastic local buckling and ultimate load-carrying capacity of the test columns. The specimens consist of two control specimens without stiffeners (unstiffened columns) and two specimens stiffened with outer-inner tubes welded stiffeners (O[sbnd]I stiffeners) in four sides of the octagonal steel section. In addition, four specimens were stiffened with two types of stiffeners: O[sbnd]I stiffeners and outer tube welded stiffeners (O stiffeners) in eight sides of the outer steel tube section. Furthermore, two hollow ratios were employed. Based on the test results, the ultimate load-carrying capacity, load-displacement curves, load-strain response, ductility, and failure modes were discussed and clarified. The test results indicated that the strength and ductility of the specimens were improved greatly by the presence of the stiffeners. The stiffeners significantly enhanced the confinement and prevented the occurrence of elastic-plastic local buckling of the outer tube. Besides, current design equations were used to predict the ultimate load-carrying capacity of octagonal CFDST stub columns. The test results were then compared with the predicted ultimate capacities of existing design equations. These predictions showed good agreement with the test results.
KW - Ductility
KW - Elastic-plastic local buckling
KW - Load-carrying capacity
KW - Octagonal concrete-filled double-skin tube
KW - Stiffeners
KW - Stub column
UR - http://www.scopus.com/inward/record.url?scp=85084065516&partnerID=8YFLogxK
U2 - 10.1016/j.jcsr.2020.106115
DO - 10.1016/j.jcsr.2020.106115
M3 - Article
AN - SCOPUS:85084065516
SN - 0143-974X
VL - 170
JO - Journal of Constructional Steel Research
JF - Journal of Constructional Steel Research
M1 - 106115
ER -