Purpose. To develop an approach for determining the stress state of plate structural elements with holes under dynamic loads with controlled accuracy. Methodology. The study was carried out on the basis of the Laplace transform and the method of integral equations. Findings. An approach to determining the dynamic stresses at the holes in the plates is proposed, which includes: the Laplace transform in the time coordinate; a numerical method for determining transformants of displacements and stresses based on the method of integral equations; finding originals on the basis of Prudnikovs formula adapted to dynamic problems of elasticity theory. The problem of determining the Laplace images for displacements is reduced to solving singular integral equations. Integral equations were solved numerically based on the approaches developed in the boundary element method. To find displacements and stresses, the Laplace transform inversion formulas proposed by Prudnikov are adapted to dynamic problems. The study on dynamic stresses at holes of various shapes was carried out. Originality. A new approach to the regularization of the Prudnikov formula for inverting the Laplace transform as applied to dynamic problems of the theory of elasticity has been developed. For its implementation: convergence of Fourier series based on pre-set stresses at the initial time is improved; the remainder is taken into account in the conversion formula. Practical value. A method has been developed for calculating the stress concentration at holes of arbitrary shape in lamellar structural elements under dynamic loads. The proposed approach makes it possible to determine stresses with controlled accuracy. The studies performed at circular and polygonal holes with rounded tops can be used in strength calculations for dynamically loaded plates. The influence of Poissons ratio on the concentration of dynamic stresses is analyzed.

At present, the use of power hydraulic cylinders is an integral part of most industrial equipment. They provide translational and horizontal movements, replacement of goods, fixation, etc. These devices are necessary elements of the equipment where application of the corresponding level of effort is applied. Often hydraulic cylinders are created specialized to perform certain types of work. It should be noted that part of the elements of the power cylinder in the manufacture is combined with welding. Such integral connections provide rigidity of installation, tightness of a design, fatigue strength at multicycle loadings. Difficult operating conditions, significant workloads, the presence of various external factors often leads to the destruction of individual elements of the cylinder. At the same time, the cost of repairing equipment that involves replacement with new power devices is quite high. This causes the implementation of repair and restoration work carried out at specialized enterprises. However, in the case of repairs, there are often a number of problems that require prompt resolution in the production environment. These should include the provision of basic materials with similar physical and chemical properties, the establishment of welding modes, the selection of the necessary welding materials, the use of appropriate techniques for conducting the arc process, etc. Therefore the repaired welded design of the case of the power hydraulic cylinder needs additional studying for weldability of separate elements among themselves, formation of a zone of thermodeformation influence. In general, the repaired hydraulic cylinder should meet the installation operating requirements depending on the purpose. The design of the considered hydraulic cylinder of the press installation is rather technological from the point of view of maintenance of automation of welding process. It contains long welds of a simple ring configuration. At the same time, the significant linear dimensions and the presence of a cylindrical surface cause some complexity in the implementation of processes. The construction material of the power hydraulic cylinder is low-carbon low-alloy steels. The analysis of technological weldability indicates a tendency to crack due to the thermal cycle of welding. The simulation of welds of the power hydraulic cylinder is performed in the work. The number of rollers was taken into account when obtaining butt welds. A comparative analysis of different electrode materials with different doping systems is done. The most applicable welding materials by chemical composition and properties of the weld metal are determined. According to the literature data and the results of comparative analysis, the optimal range of cooling rate of the main material of the hydraulic cylinder was established. The properties and structure of the zone of thermal influence of the butt welds of the power hydraulic cylinder have been studied. The magnitude of deformations and stresses caused by the thermal cycle of welding of the shell structure of the hydraulic cylinder liner is investigated. The admissible parameters of the zone of plastic deformations during butt welding are determined.

Existing elements of overpass's supporting units in pipeline transport had been analyzed. Also in this project operational loads that occur in areas of land pipelines were studied using a mathematical model that takes into account the possibility of vertical displacement supporting structure. Proposed to use welded I-beam section as a crossbar for support. Calculation of selected beams and selection geometrical sizes of elements depending on the applied load were done. We have analyzed the influence of welding cycle on the formation of stress and deformation occurring at manufacturing of metal crossbar I-section.

The article outlines advantages of applying a comprehensive approach to training specialists in the area of engineering education. Modern approaches to project management in production are analyzed, using the known experience of the European countries and the world. The basic tools of project management that are applied at all stages of implementation of engineering projects are described. Based on the analysis of known project management techniques, it has been established that effective engineering project management is possible by way of involving future professionals in the stages from developing the project idea, goals and objectives to obtaining the desired results and achieving the set goals. It is important to motivate students to think critically and encourage teamwork on a project. In the present article, the authors suggest to consider the process of training specialists in civil and industrial engineering through the prism of the next four phases of the project. The first phase is to prepare the project with elements of structuring. It addresses the issues of the project goals, tasks and results, risk management, project documentation, budgeting, formation and management of the project team. The second phase is project management, which includes drafting a project structural plan (PSP) and work packages, scheduling task completion, resources and costs planning, cost estimation, and time management tools. The third phase is the implementation of the project with control and monitoring. Here, future specialists are working on issues of the project control, financial monitoring, monitoring of resources, communication and interaction between teams, conflict management, change management and keeping necessary documentation. Completion of the project is the fourth stage, which is an integral element of project management. It provides for financial and analytical reporting, documentation for retention of experience, knowledge management, certification and feedback to the project team. Based on teaching practice and considerable practical experience in industry, the authors found out that the process of pedagogical training of future competitive specialists in various areas of civil and industrial engineering should be accompanied by practical and theoretical materials on modern tools for a holistic and integrated approach to project management. At the same time, taking account of the dynamics of political and economic changes in Ukraine and integration with international standards, it is necessary to take a skilled approach to the issue of production change management in the project activity. The global experience reveals that only truly successful organizations anticipate and initiate changes. Thus, the organizations themselves, their goals, objectives and tools are undergoing changes. And the issue of change management itself is the subject for further research by the authors.

ДІАГНОСТУВАННЯ НАпРУЖЕНЬ ЗА ТОВщИНОЮ ОБОЛОНКОВИх КОНСТРУКЦІй, щО пРАЦЮЮТЬ пІД ТИСКОМ lviv Polytechnic National university, lviv Національний університет «Львівська політехніка», м. Львів abstract. Tension and deformations which appear in the structures elements have a great impact on their durability, production accuracy and bearing capacity. The aim of this work is to develop the calculation and experimental approach to determine the distribution of circumferential tensions according to the thickness in shell structures. It is important to find the connection between the averaged values of tensions and their distribution according to the thickness using the method of supersonic tensometry to measure the tension state of thick-wall shells. First of all, the solution to the Lamé problem has been written down in order to determine the radial tensions in the cylinder. The inner wall of the cylinder is under the regular pressure. Further, in the result of the integration of this solution within the range from r min to r max , the formula has been obtained to determine the average value of tensions according to the wall thickness. The same averaged parameters are obtained after those tensions have been determined by means of the supersonic method. The value the quantity of which one can describe as a coefficient of the K transition from the average integral of circumferential tensions to their real distribution over the wall thickness is obtained in the result of the formulas relation to determine the circumferential tensions. Those numbers are relevant when using the non-destructive methods which carry the information regarding the tension condition of outer layers. The formula is derived to determine the distribution of the circumferential tensions over the wall of thick-wall shells based upon the average integral value of circumferential tension. Using the experimental methods the formulae are obtained to calculate the maximum and minimum values of circumferential tensions. keywords: tension, shell structures, supersonic method, circumferential tension.Аннотация. На основе решения задачи Ламе для определения напряжений в полом цилиндре, находящем-ся под действием равномерного давления на его внутреннюю стенку, получены выражения для вычисления распределения кольцевых напряжений по толщине толстостенных оболочек. Для исследований используются интегральные значения кольцевых напряжений в оболочке, которые определены экспериментально с помо-щью метода акустической тензометрии. Ключевые слова: напряжение, оболочечные конструкции, ультразвуковой метод, кольцевые напряжения.Анотація. На основі розв'язку задачі Ламе для визначення напружень у порожнистому циліндрі, що знаходиться під дією рівномірного тиску на його внутрішню стінку, отримано вирази для обчислення розподілу кільцевих напружень за товщиною товстостінних оболонок. Для досліджень використовуються інтегральні значення кіль-цевих напружень в оболонці, які визначені експериментально за допомогою методу акустичної тензометрії. Ключові слова: напруження, оболонко...