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Chemical treatment of municipal and industrial wastewater is becoming increasingly common in the world, resulting in sludge formation. But only a small fraction of the waste is disposed of. Therefore, the issue of the potential use of these wastes in making construction materials is vital. This paper examines the possible use of multi-tonnage industrial waste, in particular, sludge of chemical water treatment (SHVO) produced by combined heat and power plants in cement systems. Sludge of chemical water treatment is a pasty mass unstable in moisture. For this purpose it is advisable to pre-dry this waste until it becomes a fixed-mass, and then grind it. The impact of SHVO on the technological properties of cement paste and strength properties of cement stone was studied. The article shows that the introduction of SHVO into cement paste increases its water demand. The joint effect of naphthalene formaldehyde and polyester carboxylate-based sludge with additives was studied. Their efficiency depends on the way they are produced. The use of sludge with superplasticizers reduces binding agent consumption by 7.5% without loss of strength properties and reduces porosity of cement stone. It was established that the introduction of SHVO into cement systems changes the physiography of newgrowths.

The relevance of the research topic stems from the use of multi-tonnage industrial waste in cement systems. One such waste is the sludge resulted from electroplating aluminum alloy products. Galvanic (electroplating) sludge is pasty and unstable in moisture. For this purpose, it was previously dried and then grinded so it could be rationally used. Impact of sludge on technological properties of cement stone and strength properties of cement stone were studied according to standard normative methods. It is shown that galvanic sludge increases the water demand of cement paste. Therefore, the joint effect of naphthalene formaldehyde and polyester carboxylate-based sludges with plasticizing added was studied. Their efficiency depends on the way they are produced. The mixed use of galvanic sludge with plasticizing additives reduces the water-cement ratio by 20-40 %, increases the strength of cement stone within the early hardening time by 3 times and in 2 times in the grade age. The phase composition of the modified cement stone was studied using defective thermal analysis. It was established that using galvanic sludge together with plasticizing additives decreases portlandite. The article can be useful for those recycling the waste in question.

Cement concretes are strong and able to resist external adverse environmental factors, have an increased water absorption and, as a result, insufficient frost resistance and deformability. Therefore, wide use of cement concrete in road construction is limited. Modification of road cement concrete with anionactive bitumen emulsions is a current and promising solution. By introducing small concentrations of bitumen emulsions into cement concrete, one gets a material with the basic properties of cement concrete and the properties of asphalt concrete. Rigid crystallization bonds formed as a result of cement hydration are dominantly present in cement systems, while coagulation type bonds with adhesive properties bitumen prevail in asphalt systems. Depending on the quantitative relationship between these bonds, the deformability of concrete tends to change. The main technological and operational properties of the resulting road cement concrete were investigated. Cement concrete was bituminized by introducing the anionic bitumen emulsions into the concrete mixture (from 0.5% to 8.0% of cement weight), which allowed increasing technological properties of concrete mixture and the performance properties of hardened concrete. This increases mobility, improves deformability of hardened concrete, increases its abrasion resistance, water resistance, frost resistance, reduces shrinkage without reducing the strength properties of road concrete.

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The article discusses the use of unmanned aerial vehicles in solving engineering tasks. Information about the current state of the market of unmanned aerial vehicles and services with their use is provided. The most frequently used unmanned aerial vehicles and their characteristics are considered. Modern methods of obtaining and principles of processing images obtained from unmanned aerial vehicles and trends towards further development of the aerial photography process are described. The results are presented: modeling the influence of angular elements of external orientation on the accuracy of the obtained spatial coordinates of terrain points; studies of determining the volume of soil and creating a three-dimensional model of an engineering object (building) based on aerial photography obtained from an unmanned aerial vehicle multicopter. The accuracy of determining the volume of soil was controlled using a digital terrain model obtained using a total station. Control of the accuracy of building a three-dimensional model of an engineering object was performed by comparing the distances between the points of the object obtained from the three-dimensional model and the total station measurements. As follows from the results of the article, an unmanned aerial vehicle can be an effective tool for solving some engineering problems. The results obtained are comparable to the accuracy of classical methods, provided that the correct choice of the type of unmanned aerial vehicle and the correct approach to processing obtained images.

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Модель материального баланса в виде аналитической емкостно-резистивной модели (CRM) находит все большее применение для математического моделирования разработки нефтяных месторождений. В модели CRM изначально не учитывается изменение коэффициента продуктивности скважин, что значительно снижает степень применимости метода материального баланса для скважин, на которых проводятся мероприятия по интенсификации добычи. В работе предложена модификация модели CRM, которая учитывает нестационарность коэффициента продуктивности. На примере тестовых расчетов показано, что модифицированная модель CRM позволяет воспроизвести динамику дебита жидкости скважины при значительных изменениях коэффициента продуктивности.