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This article proposes a theoretically substantiated graph analytical method for studying the bearing capacity of orthotropic shell structures of minimum mass. A conceptually new approach to the analysis of optimization processes is considered. It is a rejection of the deterministic approach when exact initial data are specified and the same exact results are expected. In reality, there is some variation in the values of the initial parameters, which can significantly change the extreme values of optimization. Taking into account the sensitivity of orthotropic shells to the choice of the geometry of the force set, in this paper, optimization is carried out by constructing the region of the permissible scatter of its initial values, provided that the probable strength of the structure is ensured with its minimum weight. The numerical calculations presented in the work testify to the efficiency and visibility of the graph-analytical method, as well as its ability to carry out automated calculations. By analogy with structurally orthotropic shells by the graph analytical method, it is possible to construct the regions of optimal values of the initial parameters, when they are scattered, any material products, including objects of military equipment (during their manufacture or repair), which would provide from a given degree of probability to achieve the set goals. The proposed method for calculating the optimal structural parameters allows us to establish in a number of cases the technical requirements for the accuracy of their manufacture, which can be reflected in the DSTU standards. ; Запропоновано графоаналітичний метод дослідження міцності статично навантажених ортотропних оболонкових конструкцій мінімальної маси. Теоретично обґрунтовано метод дослідження як у детерміністичному стані величин геометричних параметрів оболонки, так і в ймовірному їх розкиді за умов найменшої маси працездатної конструкції.

This article proposes a theoretically substantiated graph analytical method for studying the bearing capacity of orthotropic shell structures of minimum mass. A conceptually new approach to the analysis of optimization processes is considered. It is a rejection of the deterministic approach when exact initial data are specified and the same exact results are expected. In reality, there is some variation in the values of the initial parameters, which can significantly change the extreme values of optimization. Taking into account the sensitivity of orthotropic shells to the choice of the geometry of the force set, in this paper, optimization is carried out by constructing the region of the permissible scatter of its initial values, provided that the probable strength of the structure is ensured with its minimum weight. The numerical calculations presented in the work testify to the efficiency and visibility of the graph-analytical method, as well as its ability to carry out automated calculations. By analogy with structurally orthotropic shells by the graph analytical method, it is possible to construct the regions of optimal values of the initial parameters, when they are scattered, any material products, including objects of military equipment (during their manufacture or repair), which would provide from a given degree of probability to achieve the set goals. The proposed method for calculating the optimal structural parameters allows us to establish in a number of cases the technical requirements for the accuracy of their manufacture, which can be reflected in the DSTU standards. ; Запропоновано графоаналітичний метод дослідження міцності статично навантажених ортотропних оболонкових конструкцій мінімальної маси. Теоретично обґрунтовано метод дослідження як у детерміністичному стані величин геометричних параметрів оболонки, так і в ймовірному їх розкиді за умов найменшої маси працездатної конструкції.

The article examines the urgent problem concerning possible destruction of a partly liquid-filled skinned capacity within the temperature field as a result of firmness loss on verge of filling level.Skinned constructions used as capacities for storing and transporting highly dangerous liquids (Level 3 of danger), such as: oil products, nitrates, alkali, low-boiling substances are often within the temperature field, and possible destruction caused by their running-out might result in catastrophic effects. Therefore, to prevent such effects, one should have good understanding of the above mentioned phenomenon as well as recommendations as for safety maintenance of these capacities. Taking into consideration the complexity of calculation chart and mathematical model of this task, the authors applied the integral transformation of Fourier to solve the task that made it possible not only to simplify the decision but to get the result in the form of exclusive formula.The analysis of the formula proves that the level of critical temperature greater depends on the ratio of radius to thickness with wide range of changes than on the coefficient of linear expansion that is close by its dimensions to basic metallic constructions. This formula and its graphic presentation make it possible in the mode of express-analysis to define durability of a partly liquid-filled skinned capacity within the temperature field that is extremely important both in the national economy and in the military sphere. ; Розглядається нагальна проблема руйнування частково заповненої рідиною оболонкової ємності при її нагріванні внаслідок втрати локальної (місцевої) стійкості під дією перепаду температури на межі рівня заповнення.

The article examines the urgent problem concerning possible destruction of a partly liquid-filled skinned capacity within the temperature field as a result of firmness loss on verge of filling level.Skinned constructions used as capacities for storing and transporting highly dangerous liquids (Level 3 of danger), such as: oil products, nitrates, alkali, low-boiling substances are often within the temperature field, and possible destruction caused by their running-out might result in catastrophic effects. Therefore, to prevent such effects, one should have good understanding of the above mentioned phenomenon as well as recommendations as for safety maintenance of these capacities. Taking into consideration the complexity of calculation chart and mathematical model of this task, the authors applied the integral transformation of Fourier to solve the task that made it possible not only to simplify the decision but to get the result in the form of exclusive formula.The analysis of the formula proves that the level of critical temperature greater depends on the ratio of radius to thickness with wide range of changes than on the coefficient of linear expansion that is close by its dimensions to basic metallic constructions. This formula and its graphic presentation make it possible in the mode of express-analysis to define durability of a partly liquid-filled skinned capacity within the temperature field that is extremely important both in the national economy and in the military sphere. ; Розглядається нагальна проблема руйнування частково заповненої рідиною оболонкової ємності при її нагріванні внаслідок втрати локальної (місцевої) стійкості під дією перепаду температури на межі рівня заповнення.

Стаття є продовженням праці [1], теоретичні дослідження в якої взяті за основу розрахунку динамічної і статичної міцності конічних оболонок. ; This article is a continuation of [1], theoretical studies which form the basis for the calculation of dynamic and static stronglysti conical shells. ; Статья является продолжением работы [1], теоретические исследования в которой положены в основу расчёта динамической и статической прочности конических оболочек.

Стаття є продовженням праці [1], теоретичні дослідження в якої взяті за основу розрахунку динамічної і статичної міцності конічних оболонок. ; This article is a continuation of [1], theoretical studies which form the basis for the calculation of dynamic and static stronglysti conical shells. ; Статья является продолжением работы [1], теоретические исследования в которой положены в основу расчёта динамической и статической прочности конических оболочек.

У статті наведено дослідження щодо підвищення динамічної міцності цистерни з рідиною при нерівномірному русі автозаправника (розгін або гальмування) шляхом розвантаження вузла з'єднання корпусу цистерни з днищем розпірно-стикувальним шпангоутом. ; The article presents the results of research on increasing the dynamic strength of a tank with a fluid in the uneven motion of the refueler (in case of acceleration or braking) by unloading the node of the tank shell with the bottom of the main frame.One of the tasks of energy saving was and is the rapid and trouble-free transportation of petroleum products to the consumer. Means of delivery are different, but it is proved that transporting up to 200 km by road tankers is more appropriate than rail, especially when it comes to providing fuel for military units in their combat operations. Hence there is the urgency of further improvement of the constructive and operational characteristics of tank-vehicles, ensuring their high reliability and compliance with environmental safety requirements.During the uneven movement of a refueler there is a fluctuation in the fluid, which results to the interaction of the shell and the bottom of the tank, in addition to the excess pressure of the saturated vapor of the component and the hydrodynamic pressure, and also to the force of the hydrodynamic impact of the moving part of the liquid, because of that the total pressure of which may exceed the limits of the strength of the construction material. In this case, damage may occur not only to internal diaphragms - damps and drainage, but also to the most dangerous - the separation of the bottom of the tank shell. The theory shows and practice confirms that the most vulnerable in extreme loading of the tank is a node of connection of the shell with the bottom, especially if the flat bottom is welded. With a dynamic impact of the moving part of the liquid, which makes up about 10% of its mass, the bottom will lose its stability, or with great probability will be torn off. Therefore, in order to unload the connection node, it is suggested to place a spacer between the casing and the bottom, a docking shaft that receives a significant portion of the load, and instead of a flat one, apply a bottom in the form of a segment of a sphere that will only work on tension.

У статті наведено дослідження щодо підвищення динамічної міцності цистерни з рідиною при нерівномірному русі автозаправника (розгін або гальмування) шляхом розвантаження вузла з'єднання корпусу цистерни з днищем розпірно-стикувальним шпангоутом. ; The article presents the results of research on increasing the dynamic strength of a tank with a fluid in the uneven motion of the refueler (in case of acceleration or braking) by unloading the node of the tank shell with the bottom of the main frame.One of the tasks of energy saving was and is the rapid and trouble-free transportation of petroleum products to the consumer. Means of delivery are different, but it is proved that transporting up to 200 km by road tankers is more appropriate than rail, especially when it comes to providing fuel for military units in their combat operations. Hence there is the urgency of further improvement of the constructive and operational characteristics of tank-vehicles, ensuring their high reliability and compliance with environmental safety requirements.During the uneven movement of a refueler there is a fluctuation in the fluid, which results to the interaction of the shell and the bottom of the tank, in addition to the excess pressure of the saturated vapor of the component and the hydrodynamic pressure, and also to the force of the hydrodynamic impact of the moving part of the liquid, because of that the total pressure of which may exceed the limits of the strength of the construction material. In this case, damage may occur not only to internal diaphragms - damps and drainage, but also to the most dangerous - the separation of the bottom of the tank shell. The theory shows and practice confirms that the most vulnerable in extreme loading of the tank is a node of connection of the shell with the bottom, especially if the flat bottom is welded. With a dynamic impact of the moving part of the liquid, which makes up about 10% of its mass, the bottom will lose its stability, or with great probability will be torn off. Therefore, in order to unload the connection node, it is suggested to place a spacer between the casing and the bottom, a docking shaft that receives a significant portion of the load, and instead of a flat one, apply a bottom in the form of a segment of a sphere that will only work on tension.