New insights into the mechanism of load transfer in steel-encased CFST connections

Song, Sha-Sha; Chen, Ju; Zhan, Xu; Pandey, Madhup

Abstract

Extensive numerical studies and analysis are presented to gain insights into the mechanism of load transfer in T- and K-type concrete-filled steel tube (CFST) connections. The new mechanism of load transfer investigated in this paper manifests that the shear load is transferred non-uniformly in the CFST column. Using validated finite element (FE) models, contact pressure stresses of the concrete-tube and angle-concrete interfaces are investigated to examine the interfacial interaction between each component. It indicates that the friction resistances between three components occur almost throughout the loading process, which is non-uniformly distributed along the column length. In addition, stress in each component is evaluated to determine the region of non-uniform load transfer in the column. For T-type connection, non-uniform load transfer shall only be considered for concrete-tube interface. For K-type connection, non-uniform load transfer should be considered for both concrete-tube and angle-concrete interfaces. Non-uniform load transfer mainly occurs in the connecting region and one time diameter of column above the connecting region for theses connections. Finally, the uneven transferred load of each component for the connections is analysed, whilst different force allocation schemes are compared. Based on the shear stresses at the tube-concrete and concrete-angle interfaces, non-uniform load transfer factor of each interface is calculated to quantitatively evaluate the non-uniformity of load transfer for the T- and K-type CFST connections.

Citation

Song, S.-S., Chen, J., Zhan, X., & Pandey, M. (2024). New insights into the mechanism of load transfer in steel-encased CFST connections. Journal of Constructional Steel Research, 214, Article 108432. https://doi.org/10.1016/j.jcsr.2023.108432

• Journal Article Type: Article
• Acceptance Date: Dec 20, 2023
• Online Publication Date: Jan 8, 2024
• Publication Date: 2024-03
• Deposit Date: Dec 5, 2024
• Journal: Journal of Constructional Steel Research
• Print ISSN: 0143-974X
• Electronic ISSN: 1873-5983
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 214
• Article Number: 108432
• DOI: https://doi.org/10.1016/j.jcsr.2023.108432
• Keywords: CFST; Connections; Design; Load transfer; Shear stress; Steel encased
• Public URL: https://nottingham-repository.worktribe.com/output/42816942
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0143974X23006594?via%3Dihub