It is light in color and has a sand paper-like surface texture. Bottom ash offers good physical chemical characteristics to replace conventional materials. Like volcanic ash and fly ash of power plants, bottom ash has pozzolans which react with the lime in the Portland cement in the concrete mix, and become very binding. Ghafoori cited three advantages to using bottom ash in lieu of sand in the concrete mix. First of all, using bottom ash alleviates the shortage of natural aggregates such as sand.
Some states actually have to import sand to make concrete.
While this is not yet the case in Illinois, it is likely to be in the future. Second, recycling the bottom ash helps the environment. Third, bottom ash may provide us with a cheaper, more economical recipe for concrete. We are optimistic that the use of bottom ash may require using less of the expensive Portland cement. An economic analysis of using bottom ash versus sand for concrete pavements is ongoing.