Development of compositions of modified concrete with improved water-repellent properties for underground parts of buildings

In building of various underground structures, one of the main tasks is to ensure the durability and reliability of concrete structures, as well as the resistance to ground and aggressive water, which, in its turn, should be taken into account in the development of concrete compositions. The wastes from the chemical and processing industry are used as additives to concrete to regulate various properties of composites. This study shows that the use of a modifier from the organic fraction of oil waste make a material with improved characteristics for its use in underground parts of structures. When solving the problem of selecting the composition of a sulfate-resistant composite with water-repellent properties, the methodology of mathematical design of the experiment was used on the basis of a polynomial model linking the optimization parameter of the compressive strength limit with independent technological factors having three levels of variation. The analysis of the results of the experiment made it possible to determine the admissible limits of the oscillations of the independent variable factors, which ensure that the optimization parameter is found not only at the extreme point, but also in the region of given values.