Electrical and mechanical properties of high-strength strain-hardening cementitious composites containing silvered polyethylene fibers

Abstract To develop multifunctional fibers for high-strength strain-hardening cementitious composites (HS-SHCC), a silver-plating technique that incorporated fibers with various pre-treatment methods using dopamine and plasma was adopted for polyethylene (PE) fibers. The effect of this plating technique on the mechanical and electrical properties of HS-SHCC was evaluated. For this, the HS-SHCC mixture with a high compressive strength of 84.1 MPa and tensile strength and strain capacity of 12.7 MPa and 8.27% was first developed. Dopamine-activated, silvered PE fiber was most effective on electroless silver plating and decreased bulk resistance of HS-SHCC by approximately 15%, potentially applicable to pavement deicing, self-sensing, electromagnetic interference shielding, etc. The PE fiber was not directly coated by the silver plating without pre-treatment, and the plasma-treated fiber provided an intermediate silver coating efficiency. The silver nanoparticles deposited on the surface of the PE fibers minimally affected the compressive strength of HS-SHCC in the range of −9% to +3% but deteriorated the tensile performance in general. The mixtures with plasma or hybrid treated silvered PE fibers provided similar tensile strengths of approximately 12 MPa to the control mixture. The silvered PE fiber with dopamine pre-treatment resulted in approximately 12% and 24% lower tensile strength and strain capacity (approximately 11.2 MPa and 6.28%, respectively) compared with the plain PE fiber; however, these tensile properties are still sufficiently outstanding, relative to other HS-SHCC types available.