Properties of Lightweight Composites Using Industry Wastes with NaOH Alkaline Activator

Abstract

Lightweight concrete has been adopted to prefabricated elements such as facades, staircases and wall systems in housing projects. Many research have been carried out on production of lightweight panels without using ordinary portland cement. The objective of this experimental study was to develop construction materials applicable to lightweight wall system by using ground granulated blast furnace slag and paper ash, which are industrial by-products. Specifically, we carried out an experimental research on the properties of a lightweight matrix that could have application to lightweight wall systems without involving any use of Portland cement that emits massive amount of carbon dioxide (CO₂) from chemical process and burning fuel; the major culprit behind global warming. In this study, we used NaOH alkaline activator to achieve the strength of a ground granulated blast furnace slag-based matrix without using general Portland cement. As a result, the mechanism was uncovered as to how NaOH alkaline activator led to the generation of hydrogen gas through reaction with the unreacted Si of paper ash. In addition, we found that construction materials applicable to lightweight wall systems could be manufactured by using ground granulated blast furnace slag and paper ash, industrial by-products.