The study of structure formation and mechanical strength properties of sulfur-containing woodcrete composites exposed to permanently acting loads

Abstract

Abstract The present paper considers the issues of mutual neutralization and toxicity elimination of toxic components of industrial by-products as well as the study of strength formation for sulfur-containing woodcrete composites exposed to various permanently acting loads and curing conditions in time. Woodcrete-concrete composites could be considered as one of the available lightweight heat insulating building materials with low heat conductivity and good sound proofing properties. The materials are based on recyclable raw materials widely available in the regions of Kazakhstan and Russia. The contemporary provisions of theory and practice of development of efficient lightweight woodcrete-concrete on the base of composite sulfur-containing binders obtained by the method of toxicity elimination and mechanochemical activation served as the methodological foundation of the research. While implementing scientific research, the authors used the standard measuring instrumentation and methods of analysis of physical and mechanical properties of woodcrete composites such as the up-to-date methods of X-ray diffraction analysis, differential thermal and microscopic analyses and testing equipment. The principle of mutual neutralization of toxic components of industrial by-products by means of mechanochemical treatment at low temperature has been applied in the paper. These methods allow reducing cement content due to its fractional replacement by industrial waste. For the experimental part of the research, ferrous iron with the oxidation number 3 (Fe2O3) has been used as the oxidizing agent, while elemental sulfur, wood coal dust and ferrous iron with the oxidation number 2 (FeO) have demonstrated regeneration properties. The properties of sulfur-containing woodcrete specimens have been studied after 7, 28 and 90 days of exposure in various curing conditions. It was stated that sulfur-containing woodcrete had been fractioned gradually, first, decomposition of mortar constituent part took place, then of organic filler fibers. The obtained results could be applied while manufacturing efficient walling material for civil engineering buildings and structures, including seismic areas.