TECHNICAL SULPHUR IN HIGH-STRENGTH AND FROST-RESISTANT CONCRETE
AIM. The repeated cyclical nature of freezing and thawing of building materials under a water-saturated conditions affects changes in the technical characteristics and durability of concrete products and structures. Harsh climatic conditions determine the necessity to produce concrete with improved physical and mechanical properties. METHODS. The effect of modifying additives on the characteristics of sulphur concrete is determined. Sulphur building materials are obtained by combining sulphur melt, fillers, aggregates and modifying additives. All known types of fillers used for the manufacture of concrete building materials can be used as components; modifying additives include both organic and inorganic substances. Physical-mechanical and operational properties of concrete significantly depend on the content and properties of components of sulphur materials. RESULTS AND DISCUSSION. A composition of sulphur concrete is developed that meets the specified requirements as well as increasing strength and frost resistance. It is determined that the optimal conditions comprise a cooling rate of 10-15 ºC per hour following the formation of a sulphur concrete mixture to a temperature of 96 ºCacross the entire surface of the product. Further cooling can be continued under natural conditions. Gradual cooling contributes to a redistribution of internal stresses and a reduction in the incidence of cracking. Under such conditions, the strength of sulphur concrete increases by 13-28%. CONCLUSIONS. The cost of products based on sulphur binders is significantly lower than all known types of concrete with improving additives. This is due to the production of associated sulphur in the processing of ever-increasing volumes of sulphur-containing hydrocarbon raw materials and a deeper purification of refined products from sulphur.