Relationship between the performance of pervious concrete slabs with steel slag and the shape properties of coarse aggregates

Abstract

The growth of cities affects their permeable surface, which can unbalance hydrological cycles. The pervious concrete can be a viable solution to combat urban environmental impacts in this subject. This type of concrete can be told apart by the presence of interconnected pores and its drainage capacity. This paper aims to analyze the relationship between aggregate shape, mechanical resistance, and permeability of pervious concrete slabs containing steel slag. A Digital Image Processing (DIP) based method was used to measure aggregate shape properties. Three different mixes, using three types of coarse aggregate (gravel 12.5 mm, gravel 9.5 mm, and coarse steel slag), and a type of fine aggregate (fine slag) were tested, and flexural strength, flow, and permeability coefficients were obtained for the slabs. Results showed the potential of using steel slag, with higher flexural strength results (4.61 MPa). Indications of the relationship between aggregate shape parameters and slab properties were determined, with more polished, more angular, and more spherical material resulting in higher flexural strength values and lower permeability coefficient. The inverse relationship between the slabs’ permeability parameters and flexural strength was observed.