Utilization of Biochar as a Multifunctional Additive in Cement-Based Materials

This article presents an experimental study on the application of processed biochar as a partial replacement of cement. Raw biochar was chemo-mechanically modified to produce super-hydrophobic carbonaceous powder (SHCP). The effects of this SHCP on paste and mortar samples were monitored in terms of compressive strength, hydration products, electrical conductivity, water absorption, and embodied carbon. The performances of the mortar samples were monitored after 7 and 28 days of sealed curing. SHCP primarily worked as inert inclusion and did not significantly affect the cement hydration. Nevertheless, the addition of SHCP as partial replacement of cement was found to decrease the water sorption, increase the electrical conductivity, and decrease the embodied carbon of the mortar samples. As such, this study provided experimental evidence that biochar can be utilized as a multifunctional additive in cement-based composites.