Effect of meso-structure on strength and size effect in concrete under compression

The effect of heterogeneity in meso level geometric and material properties on compressive strength and size effect in concrete cylinders is investigated. Crucial meso geometric parameters are identified by studying specimens belonging to three distinct gradations and spanning a range of sizes. A statistical analysis is used to account for dependencies between the parameters. Compressive strength and size effect are seen to depend on the degree of heterogeneity of critical meso parameters. For moderately sized specimens, major trends in the size effect are seen to be almost entirely explained by heterogeneity in the meso geometry; heterogeneity in meso level material properties is seen to be of comparatively less importance.