TY - JOUR
T1 - Numerical investigation and design of UHPC-encased CFST stub columns under axial compression
AU - Ayough, Pouria
AU - Wang, Yu Hang
AU - Zeng, Wenyan
AU - Liang, Qing Quan
AU - Elchalakani, Mohamed
AU - Zou, Chuanlong
N1 - Funding Information:
The authors gratefully acknowledge the financial support provided by National Science Foundation of China ( 52278144 , 52221002 ) and Fundamental Research Funds for the Central Universities ( 2022CDJQY-009 ).
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2024/3/1
Y1 - 2024/3/1
N2 - Reinforced ultra-high-performance concrete (RUHPC)-encased concrete-filled steel tubular (CFST) columns in composite construction have exceptional fire and corrosion resistance, superior load-bearing capacity, and enhanced ductility compared to standalone RUHPC and CFST columns. However, research on their behavior is limited. This paper presents a 3D finite element (FE) simulation model for accurately predicting the behavior of axially loaded RUHPC-encased CFST short columns. The model accounts for the effects of the concrete confinement provided by the steel reinforcement and circular steel tube. The existing experimental data is used to validate the FE model. The validated model is then utilized to investigate the performance of RUHPC-encased CFST columns with various geometric and material properties. The range analysis technique is applied to an orthogonal design to assess the relative significance of the factors affecting the structural behavior. The findings reveal that RUHPC-encased CFST columns have high ultimate strength and ductility. The range analysis identifies the importance order of parameters as: the compressive strength of UHPC, the steel fiber concentration, tube diameter, stirrup spacing, tube thickness, and confined concrete's compressive strength. Lastly, a simplified design model is developed to estimate the compressive capacity of RUHPC-encased CFST stub columns, providing accurate results that are verified by tests and numerical analysis.
AB - Reinforced ultra-high-performance concrete (RUHPC)-encased concrete-filled steel tubular (CFST) columns in composite construction have exceptional fire and corrosion resistance, superior load-bearing capacity, and enhanced ductility compared to standalone RUHPC and CFST columns. However, research on their behavior is limited. This paper presents a 3D finite element (FE) simulation model for accurately predicting the behavior of axially loaded RUHPC-encased CFST short columns. The model accounts for the effects of the concrete confinement provided by the steel reinforcement and circular steel tube. The existing experimental data is used to validate the FE model. The validated model is then utilized to investigate the performance of RUHPC-encased CFST columns with various geometric and material properties. The range analysis technique is applied to an orthogonal design to assess the relative significance of the factors affecting the structural behavior. The findings reveal that RUHPC-encased CFST columns have high ultimate strength and ductility. The range analysis identifies the importance order of parameters as: the compressive strength of UHPC, the steel fiber concentration, tube diameter, stirrup spacing, tube thickness, and confined concrete's compressive strength. Lastly, a simplified design model is developed to estimate the compressive capacity of RUHPC-encased CFST stub columns, providing accurate results that are verified by tests and numerical analysis.
KW - Composite columns
KW - Finite element modeling
KW - Ultra-high-performance concrete
UR - http://www.scopus.com/inward/record.url?scp=85181063243&partnerID=8YFLogxK
U2 - 10.1016/j.engstruct.2023.117387
DO - 10.1016/j.engstruct.2023.117387
M3 - Article
AN - SCOPUS:85181063243
SN - 0141-0296
VL - 302
JO - Engineering Structures
JF - Engineering Structures
M1 - 117387
ER -