Study on the Conductivity and Pressure Sensitivity Performance of Carbon Fiber Geopolymer

Abstract

This study uses slag (SL), fly ash (FA), and carbon fiber (CF) as raw materials to fabricate a conductive geopolymer, exploring the impact of CF content on its workability and mechanical performance. The conductivity and pressure sensitivity performance of the geopolymer are tested using an embedded four-electrode method. The findings indicate that the incorporation of CF reduces the fluidity of the geopolymer and shortens its setting time. With the increase of CF content, the compressive strength increases first and then decreases, while the flexural strength increases gradually when the CF content is 0.2 v%, the percolation threshold is reached, and the resistivity is 268 Ω·cm. The geopolymer exhibits good pressure sensitivity performance under both monotonic and cyclic loading. With a stress amplitude of 15 MPa and a loading rate of 1 kN/s, the specimen’s resistance change rate can reach −38.4%. The pressure sensitivity performance is optimal, with good repeatability and stability.