Analytical solution for Young's modulus of concrete with aggregate aspect ratio effect

This paper presents an analytical solution for Young's modulus of concrete with the aggregate aspect ratio effect. By taking the interfacial transition zone (ITZ)-coated aggregate as an ‘equivalent aggregate', the three-phase concrete is reduced to a two-phase composite material. The interaction direct derivative estimate is then adopted to derive an analytical solution for Young's modulus of concrete. After the validity of the analytical solution is verified with three sets of experimental results, the effects of various key factors on Young's modulus of concrete are evaluated quantitatively. The numerical results indicate that Young's modulus of concrete increases with an increase in maximum aggregate size, aggregate aspect ratio and Young's modulus of the aggregate, but decreases with increasing ITZ thickness. It is also found that the aggregate gradation has a certain influence on Young's modulus of concrete.