Effect Of Freeze-Thaw Cycling On Mechanical Properties Of Polyethylene Fiber And Steel Fiber Reinforced Concrete

This paper experimentally studied the influence of freeze-thaw cycles on the mechanical property of hybrid PE and steel fiber reinforced concretes (FRC). Five different FRC mixtures and a reference mixture were prepared for the comparative study. After 250 freeze-thaw cycles, the tension, compression, bending and fracture tests all showed that freeze-thaw cycles have minimal effect on the strength but significant influence on the deformability of FRCs. Analysis on relative dynamic modulus of elasticity and mass loss ratio indicated that the high compactness of matrix maintains the matrix integrity and thus keeps strength stability. Single fiber pull-out tests revealed the variations of peak strength and the corresponding displacement when fiber is pulled out of matrix before and after freeze-thaw treatment. It is demonstrated that freeze-thaw cycles impair the fiber/matrix interfacial bond, which is attributed to be the main cause to the degradation of deformability.(c) 2021 Published by Elsevier Ltd.