Biochar-Enhanced Cementitious Composites for Carbon-Aware Construction: A Simulated Strength- Durability-Lifecycle Evaluation

This article presents a simulated empirical study in civil engineering, materials science, and lifecycle assessment. The synthetic test matrix represented 144 concrete specimens across four mixes and three curing ages, plus 48 simulated durability specimens. A simulated concrete-mix program evaluated 0%, 1%, 2%, and 4% biochar additions by binder mass while holding water-to-binder ratio within a narrow range. Compressive strength, flexural strength, sorptivity, chloride-migration index, density, thermal conductivity, and embodied-carbon index were modeled at 7, 28, and 90 days. The biochar was assumed to originate from agricultural residue pyrolysis. A 2% biochar addition produced the strongest simulated overall balance, with 28-day compressive strength 3.8% above the control, sorptivity 11.6% lower, and embodied-carbon index 8.9% lower after accounting for stored biogenic carbon. At 4% addition, workability and compressive strength declined despite further carbon reduction. All numerical values and outcomes are synthetic and are used only to demonstrate a plausible journal-style research design. No real participants, companies, cities, laboratories, utilities, or field sites were studied. The article combines a distinct analytical structure with topic-specific metrics, visuals, and limitations so that the five papers in the issue remain independent in subject and presentation.