Assessment on Cement Mortar Containing Biochar for Carbon Neutral Wave Dissipating Block

This study provides a foundational investigation on the potential of sequestering biochar with high carbon content in wave dissipating block, especially tetrapod. By replacing some portion of cement for mortar with rice husks and wood materials in type of biochar, the research evaluates the workability and mechanical properties of biochar-mixed mortar based on varying biochar replacement ratios. The findings reveal that workability remained consistent through all replacement ratios, while mechanical properties showed variability depending on the biochar type. For rice husk biochar, compressive strength increased with higher replacement ratios, albeit with variations under different curing conditions. Both flexural and compressive strengths met standard requirements up to a 6% replacement ratio. In contrast, wood biochar showed a decline in compressive and splitting tensile strengths as the replacement ratio increased, with curing conditions significantly influencing the results. However, flexural strength remained comparable to conventional paving concrete. Overall, both flexural and compressive strengths satisfied standard requirements up to a 6% replacement ratio for both biochar types. The strengths shows possibility for replacement with biochar mortar for tetrapod material.