Durability Performances of Aramid Fiber Reinforced Polymer as Reinforcement Material for Concrete Structures in Cold Regions

Abstract

A series of tests were conducted to investigate the mechanical performances of aramid fiber reinforced polymer (AFRP) and its epoxy resin matrix after 0, 20, 40, 60 and 80 freeze-thaw cycles in the dry air, respectively. After a given number of freeze-thaw cycles, the residual tensile strength and elastic modulus of AFRP specimens were measured, and the lap-shear strength of epoxy resin adhesive specimens was gained. Test results show that: (1) Variation of the elastic modulus of AFRP with the increasing of the freeze-thaw cycles exhibits the same tendency as the tensile strength did. They increase in the first 20 to 40 cycles and then decrease till the end of 80 cycles; (2) The tensile strength and elastic modulus of AFRP decreases by 5.1% and 8.2%, respectively, after 80 cycles as compared with that kept in the laboratory environments. However, the effect of the freeze-thaw cycling in the dry air on the tensile properties of CFRP is very limited within 80 cycles; (3) The freeze-thaw cycling in the dry air of this study has an adverse effect on the adhesive property of the epoxy resin, which could be regarded as the evidence for the degradation of the interface between aramid/carbon fiber and matrix.