Experimental study on using recycled polyethylene terephthalate and steel fibers for improving behavior of RC columns
Sabry Fayed, Emrah Madenci, Alireza Bahrami, Yasin Onuralp Özkılıç, Walid Mansour
Abstract
In this research, behavior of RC columns reinforced with recycled polyethylene terephthalate (PET) and steel fibers (SF) was experimentally investigated. The experimental work includes testing of 8 columns of dimensions 150x150x1000 mm subjected to axial loading up to failure. Three volume fractions (1%, 2% and 3%) were carried out for both PET and SF. The axial/lateral displacement of the column and the transverse/vertical strain versus the load of the bars were recorded. The peak load, yield load, failure mode, ductility and stiffness of the columns were studied in detail. Influence of the plastic and the steel fibers on the concrete characteristics was experimentally investigated. Using 2% SF in the mix increased the compressive, tensile strength, and toughness of the concrete increased by 12.7%, 87.6% and 304.8%, respectively. Furthermore, enhancement rates of ultimate load capacity, stiffness, and ductility of the columns with 2% steel fibers were 15.6%, 72.6% and 34.29%, respectively. The ultimate load capacity, initial stiffness and ductility of the columns reinforced with 1% PF were 9.43, 62.6 and 19.4%, respectively, bigger than those of the column without fibers. The column capacity decreased with increasing the steel and plastic fibers over 2%. An equation of ACI was used to predict the column capacity and the results agreed with the experimental one.