Enhanced geopolymer composites with conductive fiber reinforcement: Mechanical, microstructural, and electrical curing performance

This study investigates the effects of conductive additives—basalt fiber (BF), steel fiber (SF), wire erosion (WE), and carbon black (CB)—on the mechanical and microstructural properties of geopolymer (GP) cured via electricity-driven thermal curing. A series of 13 GP mixes, incorporating varying fiber concentrations (0.25 %, 0.50 %, 0.75 %), were evaluated for compressive strength (CS), flexural strength (FS), and ultrasonic pulse velocity (UPV). The optimal formulation with 0.5 % WE, exhibited a peak CS of 65.34 MPa, a 94.36 % increase over the control. FS peaked at 16 MPa for 0.75 % WE. UPV results indicated enhanced material densification, with 0.25 % BF reaching a maximum of 2317.83 m/s. SEM/EDX analysis confirmed improved microstructural integrity, while XRD analysis verified geopolymerization.