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Reducing the negative environmental impact of a widely spread building material such as concrete is possible by decreasing the amount of cement in this composite material, especially when specific waste is included as a substitution for the binder. Another important environmental issue is accumulated aquaculture waste. This work justifies the possibility of achieving modified concrete with improved properties based on sea mussel shell powder (MSP). An improved environmentally friendly concrete was obtained and modified with MSP as a result of experimental studies. The dosage of MSP in the amount of 6% instead of part of the cement turned out to be optimal and most effective. Because of the modification, it was possible to increase the strength properties: the increments were up to 12% for the compressive strength (CS), up to 13% for the axial CS, up to 14% for the tensile strength (TS) in bending, and up to 12% for the axial TS. The ultimate strains under axial compression and tension decreased to 9% and 12%, respectively, and the elastic modulus increased to 15%. SEM analysis showed a more integral microstructure without voids and cracks in this composite with a modifier content of 6% compared with the sample of the ordinary composition. Economic efficiency is expressed in reducing the total cost of new concrete compared to traditional ones by about 17% and the cost of building construction by up to 15% due to a decrease in the percentage of defects.

In the article research results are presented, which aim to provide of automation algorithm mathematical model of designing technology clothing of the cold protection. The method of calculating heat transfer in the "human - environment" system takes into account the variable thermal parameters and the geometric dimensions of the elements, the presence of internal heat sources and convective heat transfer with the heat-carrier flow along the layers and between the calculated elements . Then the problem is reduced to a one-dimensional heat conduction problem with a variable thermal conductivity coefficient. When modeling a human body, we assume that each element of the model is represented as a set of elliptical cylinders forming the inner layers. Four main concepts of the geometric representation of the outer and inner solutions of the human body model have been developed to simulate the problems of human heat exchange with the environment. An algorithm is proposed for determining the type and structure of a mathematical model for use in CAD systems of protective clothing designing. The research was made in Don State Technical University within the framework of State Assignment of the Ministry of education and science of Russia under the project 11.9194.2017/BCh.