Hu, X.; Albareda, A.; Bu, X.; López-Almansa, F. Numerical Analysis of the Axial-Flexural Behavior of CFST Columns with Active Transverse Prestressing. Buildings2023, 13, 2411.
Hu, X.; Albareda, A.; Bu, X.; López-Almansa, F. Numerical Analysis of the Axial-Flexural Behavior of CFST Columns with Active Transverse Prestressing. Buildings 2023, 13, 2411.
Hu, X.; Albareda, A.; Bu, X.; López-Almansa, F. Numerical Analysis of the Axial-Flexural Behavior of CFST Columns with Active Transverse Prestressing. Buildings2023, 13, 2411.
Hu, X.; Albareda, A.; Bu, X.; López-Almansa, F. Numerical Analysis of the Axial-Flexural Behavior of CFST Columns with Active Transverse Prestressing. Buildings 2023, 13, 2411.
Abstract
This paper presents a numerical study on the vertical (axial) and lateral (flexure) behavior of CFST (Concrete-Filled Steel Tube) columns with active hoop prestress; this transverse prestressing effect is achieved by bolting together two steel half-tubes. This study refers to new construction only (i.e., no retrofit). 12 prototype CFST column specimens (segments) are analyzed. These specimens differ in the prestressing force (3 levels) and in the gravity loading ratio (4 levels); they are selected to represent typical ground columns of mid-rise buildings. The structural behavior of these column specimens is simulated with a nonlinear model implemented in Abaqus; the concrete and steel behavior are described with a damage-plasticity and a plasticity model, respectively. Finally, the interface concrete-steel interaction is represented by a hard (compression-only) surface-to-surface contact model. The calculations involve three consecutive loading steps: (i) transverse prestress, (ii) axial force, and (iii) lateral loading (shear force and bending moment). The structural behavior of the CFST columns is deeply examined and discussed; the results show that their axial-flexural capacity is adequate. Noticeably, it is concluded that the overall benefits of prestressing the columns are only modest. Preliminary studies on the aforementioned mid-rise buildings equipped with the CFST columns show that their gravity and wind capacities are largely enough; conversely, their seismic capacity is sufficient for moderate seismic ground motions only.
Keywords
seismic behavior; mid-rise framed buildings; composite building columns; concrete-filled steel tubes; confinement effect; active hoop prestress
Subject
Engineering, Civil Engineering
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
