Analytical Study of Force–Displacement Behavior and Ductility of Self-centering Segmental Concrete Columns

Abstract

In this study the behavior of unbonded post-tensioned segmental columns (UPTSCs) was investigated and expressions were proposed to estimate their ductility and neutral axis (NA) depth at ultimate strength. An analytical method was first employed to predict the lateral force-displacement, and its accuracy was verified against experimental results of eight columns. Two stages of parametric study were then performed to investigate the effect of different parameters on the behavior of such columns, including concrete compressive strength, axial stress ratio, diameter and height of the column, axial stress level, duct size, stress ratio of the PT bars, and thickness and ultimate tensile strain of fiber reinforced polymer wraps. It was found that the column's aspect ratio and axial stress ratio were the most influential factors contributing to the ductility, and axial stress ratio and column diameter were the main factors contributing to the NA depth of self-centering columns. While at aspect ratios of less than ten, as the axial stress ratio increased, the ductility increased; at aspect ratios higher than ten, the ductility tended to decrease when the axial stress ratio increased. Using the results of parametric study, nonlinear multivariate regression analyses were performed and new expressions were developed to predict the ductility and NA depth of UPTSCs.

Self-Centering Prestressed Concrete Pier Considering the Effect of Vertical Earthquake Motions with External Aluminum Dissipators

“…Under unidirectional earthquake, the drift of the RC pier tilted completely to one side, led to the maximum drift of the RC is much larger than the SCPC pier system. (1) H+V earthquakes (2) Scaled factor ratios (H/V) ( The residual drifts of the SCPC pier are 0.013% under unidirectional earthquake record and 0.015%, 0.03% under the impact of the vertical earthquake component, the changing of the SCPC residual drift is insignificant. Contrary to the SCPC pier, the seismic behavior of the RC pier under earthquakes leads to large damage to the bridge structure.…”

Effect of Rubber Heat Treatment on Rubberized-Concrete Mechanical Performance

“…Concrete structures subject to severe loading conditions are critical structural components. Many of these structures have been severely damaged or collapsed under severe loading due to inadequate strength, ductility, or toughness [1][2][3][4][5][6][7][8][9]. The low energy dissipation of conventional concrete structures is one of the main reasons behind this severe damage.…”