Durability of sustainable sulfur concrete with fly ash and recycled aggregate against chemical and weathering environments

Abstract

Fossil fuel consumption is rapidly increasing all over the world, and so is the amount of sulfur yielded as a byproduct of petroleum refining processes. A huge cost of waste disposal will be demanded if no counterplan is prepared for constantly growing sulfur production. As an innovative solution, using sulfur for the role of a binder in concrete has been recently pursued to replace entire cement and water. This study investigates the mechanical and durability properties of sulfur concrete made with fly ash and recycled aggregate; effects of the sustainable materials are explored as an effort to maximize the sustainability of sulfur concrete. Based on the results of preliminary tests, three types of mix proportions are designed for further investigation. The key test variables are the partial replacement of modified sulfur by fly ash and the type of coarse aggregate (natural or recycled). In all concrete mixtures, neither cement nor water is included. The durability properties of sulfur concrete in severe chemical and weathering environments are explored, including chemical resistance, freezing-thawing resistance, and coefficient of thermal expansion. Essential mechanical properties such as compressive and tensile strengths and elastic modulus are also examined.