Performance and Sustainability of Concrete Mixes Designed by ACI 211 and BS EN 206

Concrete is the most widely used construction material globally due to its versatility, cost-effectiveness, and structural reliability. However, differences in mix design standards can significantly influence its performance, durability, cost, and environmental impact. This study presents a comparative evaluation of concrete mixes proportioned according to the ACI 211.1 and BS EN 206 standards, with emphasis on mechanical performance, durability, and sustainability. Ordinary Portland cement, potable water, and well-graded fine and coarse aggregates were used to design and cast C24/30 concretes. Experimental investigations included slump, compressive strength at 3–90 days, sorption, porosity, water absorption, sorptivity, chloride penetration, surface resistivity, and acid resistance. Cost and embodied carbon analyses were also performed. The ACI 211.1 mix achieved consistently higher compressive strengths (12–28% above BS EN 206), lower sorption, porosity, and chloride permeability, reflecting superior durability. However, it suffered greater weight loss under acid attack and incurred higher production costs (~ 3% increase) and embodied carbon (~ 5% increase) due to its higher cement content. On the other hand, the BS EN 206 mix, while delivering lower strength and durability indices, offered better cost-efficiency and reduced carbon footprint. It is recommended that the ACI 211.1 approach be adopted where high strength and durability are critical, while BS EN 206 offers a more sustainable option for cost- and carbon-sensitive applications.