The document presents mix design calculations for concrete achieving a characteristic strength of 40 N/mm² at 28 days, following the BRE 1992 method as recommended by the UK Department of the Environment. It includes detailed components such as cement content, water-cement ratios, aggregate proportions, and densities, with summaries for different concrete mixtures. Various trials and their respective quantities for materials per cubic meter are also provided to ensure accurate mixing for desired concrete performance.