Based on a combination of a system-oriented approach and a synergetic concept, the requirements for the design of tribological polymer composite materials with high-modulus fillers are formed. These materials are considered as an open dynamic system that evolves during operation. The principles of the synergetic concept for tribotechnical systems taking into account the theory of evolution and self-organization to ensure its self-governing and self-supporting development are considered. It is revealed that in the process of interaction of elements of the tribosystem the cooperation of local areas of their materials is formed with the emergence of a critical number of such areas and the creation of an information field about their functioning. The direction of self-organization of processes and states of parts materials in the tribotechnical system and expediency of using the conclusions of the synergetic concept in the construction of polymer composite materials, as well as their nonequilibrium are shown. The issues of creation of tribophysical bases of wear resistance of tribotechnical systems with conjugations of the details made or strengthened by polymeric composite materials are considered. Polymer composite materials are considered as a set of interacting ensembles of local areas, the principle of maximum wear resistance (reliability) is used. Tribological principles and requirements to creation and substantiation of expediency and efficiency of use of high-modulus fillers in polymers are formulated
Methods for determining the characteristic values of climate loads at the location of a building have been perfected. Based on comparative analysis, the method of levelling the values of climate loads with an exponential or triangular weight function is recommended. For four climate loads, appropriate equalization intervals are determined, ensuring the maximum amount of weather data taken into account, while maintaining their uniformity. In construction, the determination of the climate load is important for the location of the building. When prescribing building standards, the values of the climate load are determined according to the data of weather stations in relative proximity, which provides values within the limits of reliability. Such an approach can lead to an overestimation of the characteristic values of climate loads and consequently increase the consumption of the construction materials of the building or, in the opposite case, decrease the unnecessarily high-energy consumption to condition the space inside the building.
This study proposes a method of administrative-territorial zoning of the major design parameters of the air temperature. For each administrative region, the design values of the mean temperature of the year, the temperatures in the coldest and the warmest month, and the temperature of the coldest and the warmest day are set. These parameters can be applied during the building and in the structural design of the entire region. The study was conducted in Ukraine, however, is applicable to all countries.
The article provides an analytical justification of the flow of tribological processes of coupling of "shaft-sleeve" parts, which simulates the functioning of sliding bearings and cylindrical joints of machines. The main attention is paid to such characteristics as contact pressure, static and dynamic forces, the criterion of the product of the total pressure on the sliding speed, the work of friction forces and its transition into thermal energy in the friction zone for polymer (based on polyamide P-68) and polymer-composite coatings (based on P-68 with kaolin filler) on the working surfaces of the parts. A comparative analysis of the functioning and tribological characteristics of the couplings of parts without coatings is presented. Experimentally, on the basis of tests of samples on the MИ-1M friction machine, a significant reduction in wear and an increase in the relative wear resistance of samples with polymer-composite coatings in the modes of friction without lubrication (by 1.3...1.4 times) and marginal friction (in 1.2...1.3 times), as well as a decrease in the temperature in the friction zone (365 K and 347 K) compared to the polymer coating.
The aim of this work is to improve a method for determining the characteristic values of climatic loads according to a probabilistic model of the annual maxima sequence, by choosing a rational type of generalized extreme value distribution law. An analysis is provided regarding the suitability of using four types of distributions for describing a data collection of maximum values of climatic loads. Using example data from the meteorological stations of Ukraine, it is found that for coefficients of variation smaller than 0.85–1.0, it is advisable to use the double exponential Gumbel distribution (generalized extreme value distribution type-I), and at higher values of the coefficient of variation, it is advisable to use the Weibull distribution (generalized extreme value distribution type-III). Recommendations are provided for considering the accuracy in the estimations of the characteristic values of loads according to the probabilistic model for the annual maximum value series.
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