Coarse Aggregate Grading Effect on the Correlation Between Compressive and Flexural Strengths of Concrete

Abstract Existing models relating compressive and flexural strengths often fail to align with our experimental findings. A preliminary study highlighted that many authors should have considered the influence of varying coarse aggregate grading. Consequently, an empirical investigation was conducted to assess the impact of coarse aggregate grading on compressive and flexural strengths and the interrelationship between these strengths through the tensile coefficient Kt. The central objective is formulating a suitable empirical equation for the fluctuating coarse aggregate grading that connects compressive and flexural strengths. The reliability of the proposed equations was evaluated using the integral absolute error (IAE). Results underscore that coarse aggregate grading exerts a noticeable effect on compressive and flexural strengths, with the latter being more susceptible. The relationship between these strengths is also influenced, exhibiting two distinct fields of variation. A novel parameter, FCR, is introduced to quantify coarse aggregate grading variance within these two fields. Optimal flexural strength outcomes are achievable by employing coarse aggregate grading with an FCR greater than five. Two equations associating compressive and flexural strengths are proposed, introducing two distinct values for the tensile coefficient Kt.