Revolutionizing eco-friendly concrete : unleashing pulverized oyster shell and corncob ash as cement alternatives for sustainable building

Abstract

The utilization of Portland cement (PC) as a conventional binder in concrete production is not completely eco friendly, spurring research into finding a more ecologically friendly way to produce concrete. This study recycles waste materials such as corncob ash (CCA) and pulverized oyster shell (POS) as alternative binders at 5–15 wt% of PC for ternary blended concrete (TBC) production and tested for mechanical properties after 3–120 curing ages and durability performance after 120 days of immersion in 5 % of acidic and sulfate solutions. The embodied energy (EE) and global warming potential (GWP) of TBC compositions were analyzed within cradle-to-gate constraints, and the sustainability and economic indexes were evaluated. Microstructural characterization was performed on concrete samples after 28 curing ages. The results indicated that CCA and POS incorporation reduced TBC’s slump and early age strengths. However, the later age strengths were superior at 10 wt% CCA and POS replacement level with 1–8 %, 1–7 %, and 1–9 % increases in compressive, flexural, and split tensile strengths after 28–120 curing ages compared to the control samples. Adding 10 wt% CCA and POS contents to TBC enhances its resistance to chemical attacks, reduces its EE and GWP by 19–25 % and 19–20 %, and increases its sustainability score and eco-strength efficiency by 25 and 17 % compared to the control concrete. Incorpo rating CCA and POS into the TBC mix contributes C-A-S-H for strength development. Ultimately, this study offers ecofriendly and durable concrete at 10 wt% CCA and POS substitution for sustainable building.