Patil, Dada S.2026-06-012026-06-012026-05https://www.nbmcw.com/product-technology/construction-chemicals-waterproofing/concrete-admixtures/implications-of-aggregate-geological-origin-for-rcc-design-under-indian-standard-456-2025.htmlhttp://aiktc.ndl.gov.in/handle/123456789/4518The inclusion of aggregate geological origin in elastic modulus estimation under draft IS 456:2025 marks a significant shift in RCC design approach. Dr. Dada S. Patil, examines how this move from strength-based to a more material-sensitive approach could influence structural behaviour, serviceability predictions, and overall design accuracy, and highlights the technical, practical, coordination, and contractual challenges in aligning design assumptions with on-site conditions.en-USArticle