The article discusses various mechanisms of self-healing of concrete used in the construction of buildings and structures designed for certain operating conditions and the environment, which saves resources and time during maintenance and repair of objects for various purposes. Types of self-healing of concrete: With hollow fibers; Microcapsulation; Expanding additives; Bacteria. Conclusions. Today, progress has been made in understanding the relationship between the structure of materials and their properties. Thanks to the knowledge gained about the structure of materials, the possibility of designing materials of directional quality was considered, which guarantees their compliance with certain operating conditions and the environment.

Keywords: concrete, destruction, self-healing, hollow fibers, microcapsulation, expanding agent, bacteria

The system for measuring cargo dimensions is designed for streaming measurement of cargo dimensions, which can be luggage at airports and transshipment bases, various parcels, as well as commercial cargo. The authors of the article developed a structural and functional diagram of a control and measuring system for dynamic measurement of cargo dimensions, and also considered the principles of its operation.

Keywords: control and measuring system, measurements, cargo dimensions, luggage, automated systems

The article considers the possibility of improving the physical, mechanical and environmental properties of polymer concrete by changing their component composition depending on the requirements for the operational characteristics of the construction object. Currently, the research of scientists is aimed at the development and implementation in construction practice of compositions of light building materials, the range of densities of which varies depending on the tasks set. Such an additive as glass, changing the physical properties of the material, significantly improves its characteristics, there are the following types of such concrete: glass concrete with fiber, concrete with optical fiber, with cullet, and also a solution where glass is used as a binding element. Liquid glass, when added to concrete, helps to improve the stability and strength of plaster and concrete structures. When using this material, you can find a lot of positive things. The environmental friendliness of the material expands the scope of its use, which is very important at the present time. The new material is easy to obtain, is made from affordable materials, has improved physical and mechanical characteristics, which makes it competitive among a wide range of products on the global construction market.

Keywords: polymer concrete, liquid glass, glass concrete, optical fiber, cullet, modification, strength, composite material, glass fiber concrete, secondary raw materials

For the long-term operation of a power oil transformer, it is necessary to comply with all regulated checks of its technical condition, prescribed in the instructions. The current regulations provide for daily routine inspection and technical examination at least once a week. Famously, the heating of a power transformer during its operation is linked to the presence of active losses in the windings and core. High power transformers have impressive heat losses. Oil cooling systems are used to prevent that overheating of the transformer and damage to the insulation of the coil windings. The deterioration of the quality of the transformer oil causes an increase in active losses, due to which the efficiency of the power device decreases. This negatively affects the process of converting electrical en-ergy. The conclusion is that the quality of the oil directly affects the longevity of the power transformer. Thus, the most important functional elements from a control point of view are the transformer oil and the coil of the power device. Based on the foregoing, the urgent problem of technical control of electrical substations’ transformers is the development of methods and devices for express monitoring of the functional state of power oil transformers, which allow quick diagnostic information receiving, sufficient for a timely decision on the need for unscheduled repairs or maintenance.

Keywords: power transformer; transformer oil; impedance; diagnostics; functional state; dielectric loss tangent; equivalent circuit; MathCad