Impact of Aggregate Physical Properties on the Compressive Strength of Concrete

Understanding the role of aggregates in the compressive strength of brittle composites is crucial for optimizing construction material usage. In this study, we employed the rigid-body-spring-network model validated with experimental data. Through uniaxial compression loading tests on concrete, considering Young’s modulus and compressive strength of the coarse aggregate as variables, we elucidated how the coarse aggregate’s physical properties influence concrete's compressive strength, illustrated using a straightforward diagram. When the coarse aggregate’s Young's modulus is lower than the mortar's, the stress transfer path within the mortar bends and cracks more rapidly, significantly lowering strength. Conversely, if the coarse aggregate’s Young’s modulus exceeds that of the mortar, stress becomes concentrated in the aggregate, and the crack of the coarse aggregate governs the failure of concrete.