Influência da espessura e do volume da pasta de cimento nas propriedades dos concretos permeáveis (Influence of cement paste thickness and volume of on pervious concrete properties)

This study aimed to identify the influence of replacing coarse natural aggregate with coarse recycled concrete aggregate on the thickness and volume of the cementitious paste under the variation of the water/cement ratio in the fresh and hardened properties of pervious concrete. The determined theoretical paste thickness was inefficient for pervious concrete dosage. However, it was found that the paste volume was the parameter that was best related to the mechanical and permeability properties of the studied material. Pervious concrete with natural aggregates showed higher compressive strength than concrete with recycled aggregates, although both met the regulations. All the concretes produced, except one with recycled aggregate of w/c ratio 0.25, reached the tensile strength in the minimum design bending. Pervious concrete with recycled aggregates showed more significant mass loss by abrasion and more porosity than concretes with natural aggregates. Finally, all pervious concretes presented permeability coefficients greater than the lower limit determined by the standard.