Effect of loading strain rate and short PVA fibers on the tensile mechanical performance of carbon TRM

Abstract

AbstractTextile reinforced mortar (TRM) is an alternative reinforcement material in terms of fiber reinforced polymer (FRP) intervention due to the excellent compatibility with the substrate. The coupling effect of the seismic strain rate (10−4−10−1 s−1) and short polyvinyl alcohol (PVA) fibers on the mechanical properties of carbon TRM was studied under the uniaxial tensile load. Forty groups of tensile samples were designed to obtain the relationships between the strain rate and the volume content of PVA fibers, as well as the number of grids and types of matrices. The crack distribution, failure mode and stress–strain responses of the tensile samples were presented. The results showed that the crack and peak strength can be enhanced to 4.0–7.2 MPa and 10.1–17.3 MPa when the strain rates ranged from 10−5 to 10−1 s−1, respectively. The strain‐rate sensitivity in the crack and peak strength was confirmed. Short PVA fibers and reinforced textile grids can effectively enhance the crack and peak strength and improve the crack pattern under the static and seismic strain rates. Finally, based on the strain rate and short fibers index, a quantitative model was proposed to estimate the tensile strength of TRM under the static and dynamic strain rates.