Behavior of Plastic-steel Fiber Reinforced Lightweight Aggregate Concrete Columns Subjected to Concentric Axial Loading

Abstract

This paper presents the findings of an experimental study on the behavior of plastic-steel fiber (PSF) reinforced lightweight aggregate concrete (LWC) columns under axial compression loading. The experimental variables were concrete compressive strength, main reinforcement percentage, and PSF volumetric ratio. The behavior of the PSF reinforced LWC columns was evaluated in terms of the failure mode, load-bearing capacity, steel reinforcement strain, and ductility. The results showed that the addition of PSFs not only prevented premature spalling of the concrete cover but also strengthened the bond between the LWC and the steel bar. Compared with that of the control specimen, the ductility of the fiber-reinforced columns improved significantly. In addition to the experimental program, a numerical investigation based on nonlinear finite element (FE) analysis was performed using ANSYS 10.0. The experimental and numerical results were compared and found to be in satisfactory agreement. Furthermore, an analytical model developed in a previous study was used to predict the load-bearing capacities of the PSF reinforced LWC columns. The compressive strength of concrete, the spacing, and yield strength of transverse reinforcement were considered in the analytical models, and the analytical predictions were in agreement with the experimental results.