Relationships between density, porosity, compressive strength and permeability in porous concretes: Optimization of properties through control of the water-cement ratio and aggregate type
Carlos Sánchez-Mendieta, J. J. Galán, Isabel Martínez-Lage
Abstract
In this study, the relationships between density, porosity, compressive strength, and permeability in porous concretes were examined. Coarse aggregates, sourced both from natural riverbeds and through crushing, were used with water-to-cement ratios of 0.35, 0.38, and 0.41. Direct correlations were found between density and compressive strength, while porosity was inversely related to strength. Additionally, a direct correlation was observed between porosity and permeability. Adhering to the ACI 522R-10 standards resulted in compressive strengths approaching 12 MPa and permeabilities ranging from 13.5 to 26.1 mm s⁻ 1 . These findings emphasize the importance of aggregate type and size in optimizing porous concrete properties without requiring fine aggregates or additives. Discrepancies with previous studies are attributed to variations in materials, mix designs, and testing methods. Thus, precise control of the water-to-cement ratio and careful aggregate selection are crucial for tailoring porous concrete to specific applications. • Different types of aggregates and mix proportions were studied to optimize the balance between porosity, permeability, and compressive strength in pervious concrete. • Results show that crushed aggregates improve compressive strength, while river aggregates enhance permeability. • Increasing the water/cement ratio and void content reduces density and compressive strength, but increases porosity and permeability. • A direct relationship was established between density and compressive strength, and between porosity and permeability, both of which are key factors in the design of pervious concrete.