Produção industrial de blocos de concreto para alvenaria à base de rocha vulcânica ácida álcali-ativada

Abstract

Society's growing awareness of environmental degradation and the consequences of increased greenhouse gas emissions, coupled with the rising demand for raw materials in the construction industry, has spurred the search for more sustainable building materials and practices. Focusing on alkali-activated materials as an alternative, this research addresses a gap in the literature by integrating technical, environmental, and economic aspects, particularly on an industrial scale. Therefore, this study aims to provide a significant contribution to the development of industrial-scale production of alkali-activated concrete blocks using a mining byproduct (acidic volcanic rocks). This entails a comprehensive assessment of technical aspects, such as dimensional stability, water absorption, compressive strength, and water resistance, as well as environmental considerations, including CO2 emissions and embodied energy, along with large-scale production costs. The results demonstrate that, although these blocks exhibit lower strength compared to Portland cement, they meet the regulatory requirements established by NBR 6136 for use in construction. Furthermore, they present a substantial potential for reducing CO2 emissions (32% to 52%) and energy consumption (11% to 19%). Cost analysis revealed only a 2% increase compared to Portland cement. In this context, it was possible to evaluate, for the first time, the technical, environmental, and cost viability of producing concrete blocks using alkali-activated cement derived from acidic volcanic rock as a binder on an industrial scale. The consolidation of these results highlights the potential of using acidic volcanic rocks as a viable alternative to Portland cement in concrete block production.