Effects of non-ground slag and bottom ash as fine aggregate on concrete permeability properties

In this study, the effect of non-ground coal bottom ash (NGCBA) and non-ground granulated blast furnace slag (NGGBFS) on permeability properties regarding durability of concrete is investigated. The mentioned by-products have been used as fine aggregate substitute in the production of concrete. Some permeability-durability tests have been conducted on the specimens produced using these by-product fine aggregates. Tests to be done were chosen as rapid chloride permeability, freezing-thawing and drying-wetting tests. Furthermore, microstructures of these concrete types have been observed. Thus, the effects of chemical, physical and mechanical properties of NGGBFS and NGCBA fine aggregates on the permeability of concrete can be obtained in a much better perspective and discussed easily. The optimum replacement ratio of these by-products as fine aggregate is also attempted to be determined for producing low permeable concrete. Consequently. NGBFS and NGCBA generally increase permeability by increasing porosity due to their physical properties but it can be said that these by-products as fine aggregate can also reduce permeability of concrete due to their chemical and mechanical properties in terms of permeability-durability tests. Therefore, usage of these by product types improves durability properties related to the permeability of concrete. (C) 2011 Elsevier Ltd. All rights reserved