Properties of permeable ceramic brick prepared with felsite tailing

Using tailings to prepare permeable brick is a promising approach to solve the existing problems of tailing being hugely generated. In this paper, the felsite tailing with size of 0.3–4.75 mm is used to prepare the permeable ceramic brick, and the influence of aggregate size on porosity, permeability, mechanical properties and frost resistance are investigated. The coarser aggregate could increase the porosity, pore retention efficiency and permeability of permeable brick. In addition to porosity, the strength of permeable brick is also related to the aggregate gradation. The permeable bricks with four-grade aggregate generally have higher compressive and flexural strength than that with single- and two-grade aggregate, and using four-grade aggregate could prepare a permeable brick with both high permeability and higher strength. More importantly, the ratio of flexural to compressive strength of permeable ceramic brick is about 0.65, which is obviously higher than that of ordinary pervious concrete. Under the freezing-thawing environment, the mass loss of permeable brick is very low, and the increase of finer aggregates could restrain the strength loss of permeable brick.