The effects of aggregate and fiber characteristics on the properties of pervious concrete

This paper investigated the mechanical and permeability performances of pervious concrete mixtures produced using different aggregates and fibers. Basalt, limestone, travertine, and pumice aggregates were used at two fractions (5-12 mm and 12-19 mm) with steel and polypropylene fibers. In the scope of experimental program, slump, rheology, unit weight, compressive strength, flexural strength, splitting tensile strength, abrasion resis-tance, porosity, and permeability tests were performed on pervious concretes. As a result of this comprehensive laboratory investigation, pervious concrete specimens exhibited adequate mechanical performance for structural applications by achieving 8.8 MPa compressive strength, 3.0 MPa flexural strength, and 2.2 MPa splitting tensile strength. Besides, the fiber-reinforced mixtures reached a high deflection capacity, which was a significant parameter for pavements constantly exposed to fatigue-originated tensions. In addition to superior strength performance, the highest porosity and infiltration rate results were obtained as 29.5 % and 13.91 mm/s, respectively. Steel fiber inclusion notably increased the abrasion resistance, while the polypropylene fiber remarkably enhanced the permeability performance. It was revealed that pervious concrete specimens could achieve an excellent infiltration rate (>10 mm/s) using polypropylene fiber, regardless of the aggregate type. Limestone, basalt, and travertine generally achieved similar results, while pumice exhibited poor performance compared to other aggregates. Also, it was determined that using smaller-sized and more uniform aggregates generally increased the total performance of pervious concrete specimens.