Biochar and recycled carbon fibres as additions for low-resistive cement-based composites exposed to accelerated degradation

Biochar (BCH) and recycled carbon fibres (RCF) were used as carbonaceous additions in low-resistive mortars/ concretes. Their effects on mechanical, electrical, and durability properties were investigated. Tests were per-formed both during curing and accelerated degradation. The combined use of RCF and BCH decreased the electrical impedance of cement-based matrices, enabling the use of low-cost monitoring instrumentation, and improved their mechanical performance. Recycled carbon fibres and biochar additions increased carbonation and capillary water absorption but acting as a barrier they made water and chlorides penetrate less deeply.

Automated summary

Biochar and recycled carbon fibres were added to low-resistive mortars/concretes and their effects on mechanical, electrical, and durability properties were investigated. The combined use of these additives improved the mechanical performance and decreased the electrical impedance of the cement-based matrices. Moreover, they increased carbonation and capillary water absorption but acted as a barrier against water and chloride penetration.