Structure formation, rheology and properties of sulfur concrete mixtures and sulfur concrete modified with bitumen and stone flour

Abstract

The development and improvement of cementless concrete, including by use of various types of refuse, is especially important due to their economic and environmental efficiency. Sulfur as a refuse of the oil and gas industry can act as the production of a binder of a new environmentally friendly building material - sulfur concrete (SC). The purpose of the study was to improve effective designs of SC containing refuse from the oil and gas and stone processing industries, and to analyze their rheological and physical and mechanical appearances. Methods of laboratory testing of SC samples, as well as microscopic analysis of its structure, were applied. SC with the best values of compressive strength (CS) and water occlusion has the following formula according to the content of the main components: sulfur - 20% of the mass; stone flour - 10% of the mass; crushed stone - 40% of the mass; sand - 30% of the mass; bitumen modifying additive - 6% by weight of sulfur. The mobility of these combinations is enhanced by up to 2.2 times by adding a bitumen addition to SC formulations. Compared with the control design, the optimal design of modified SC presented an enhancement in CS up to 105% and a reduction in water occlusion up to 70%. The structure of samples of SC of the optimal design does not have shrinkage cavities and pronounced phase boundaries, in contrast to the SC of the control design.