Effective Young's modulus estimation of concrete

摘要

A two-step analytical procedure is proposed toevaluate the quantitative influence of the maximum aggregate sizeand aggregate gradation on the effective Young's modulus ofconcrete. In the first step, the effective Young's modulus of aspecified "basic element," which is composed of an aggregatecoated with interfacial transition zone and again covered withcement paste, is obtained based on a proposed four-phase spheremodel. The theory of elasticity and Eshelby's equivalent mediumtheory are used to achieve the goal. In the second step, the rule ofmixture method is used to estimate the effective Young's modulusof concrete. Following the two-step procedure, the maximumaggregate size and aggregate gradation are included in theformulations for the effective Young's modulus of concrete. Thecalculated results are compared with experimental results from theliterature. The comparison results show a reasonable agreementwhen isostrain is assumed for every basic element in the secondstep. Parameters influencing the effective Young's modulus ofconcrete are discussed via calculated results.