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Since in Ukraine there are fines for imbalances in solar power generation in the “day-ahead” energy market, the forecasting of electricity generation is an important component of the solar power plant operation. To forecast the active power generation of photovoltaic panels, a mathematical model should be developed, which considers the main factors affecting the volume of energy generation. In this article, the main factors affecting the performance of solar panels were analysed using correlation analysis. The data sets for the construction of the forecasting model were obtained from the solar power plant in the Kyiv region. Two types of data sets were used for the analysis of factors and model building: 10-minute time interval data and daily data. For each data set, the input parameters were selected using correlation analysis. Considering the determining factors, the models of finding the function of reflecting meteorological factors in the volume of electricity generation are built. It is established that through models with a lower discreteness of climatic parameters forecast it is possible to determine the potential volume of electricity production by the solar power plant for the day-ahead with a lower mean absolute error. The best accuracy of the model for predicting electric power generation over the 10-minute interval is obtained in the ensemble random of a forest model. It is determined that models without solar radiation intensity parameters on the input have an unsatisfactory coefficient of determination. Therefore, further research will focus on combining a model of forecasting the day-ahead solar radiation with 10-minutes discreteness with a model for determining the amount of electricity generation. The determined predicted values of solar radiation will be the input parameter of the forecasting model described in the article

During construction of bridges, the possibility of flooding periods should be considered. Therefore, it is necessary to understand the degree of possible deformation of wooden structures and calculate the limit of their plasticity and elasticity at different values of moisture content. Thus, the purpose of study is to find the method for determining the relative critical deformations of wood with different moisture content and analyse the dynamics of their change. Problems of a deformable solid material were investigated by the analysis of a model of complete deformation diagram “stress σс – deformation uс ”, methods of mathematical statistics, and systematic analysis of experimental results. This study allowed formulating the method for determining the relative critical deformations of solid wood at different moisture levels by axial compression along the fibres of experimental samples. Based on the experiment results, the formula for determining the relative critical deformations of solid wood with different moisture was proposed. The dynamics of changes in critical relative deformations at different moisture, and its elastic and plastic components were presented. It was found that in case of drying wood from 30 to 12%, the plastic component of relative critical deformations decreases and the elastic one, on the contrary, increases. The findings can be used in the deformation calculation methodology for wooden elements and structures of bridges, hydraulic structures, buildings, taking into account the changes in the moisture content of the material

An analysis of modern testing equipment to establish the mechanical properties of different in structure and origin of building materials. As a result, it was established, that the most effective for testing are foreign electromechanical and servo-hydraulic machines of different configurations. It is determined that this type of technical systems allows to study different types of materials, including high-strength, compressive, tensile, bending and other types of loads in accordance with current international regulations. The article analyzes the principles of operation of the universal test machine INSTRON and the universal servo test machine UIT STM 100S. The configuration of such modern technical systems involves the availability of electronic computers and software, which allows testing in automatic mode, program research factors, determine the current and maximum values of mechanical properties of building materials, perform mathematical calculation of characteristics, reproduce information on the device screen, build research diagrams in electronic and printed form. It has been found that the advantages of such test machines are a load of up to 60 tons. It was determined that the universal machine UIT STM 100S is characterized by a large traverse stroke and a wide range of test speeds, which allows to expand the solution of quality control problems in industry. It is also established that the UIT STM 100S has software that includes a standard library of test methods according to regulatory documentation. The advantages of such a machine are the possible expansion of the standard information base necessary for the operation of the standards or the installation of an additional software module that provides the ability into independently supplement the standard library. Given the wide range of measurements of the universal testing machine UIT STM 100S, we envisage its use for the study of deciduous and coniferous wood in modern rigid test mode.