APPLICATION OF THE MAPLE PACKAGE FOR CALCULATING THE RIBBED PLATE FOR STRENGTH, TAKING INTO ACCOUNT THE DISCRETE LOCATION OF THE RIBS

This paper presents an analytical calculation of the stress-strain state of a ribbed plate supported by a cross system of stiffeners. The calculation was carried out by the Ritz method using the Maple mathematical package

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Investigation of the stress-strain state of beams with different types of web perforation

Scientific journal of the Ternopil national technical university ◽

10.33108/visnyk_tntu2021.03.079 ◽

2021 ◽

Vol 103 (3) ◽

pp. 79-87

Author(s):

Ivan Pidgurskyi ◽

Vasyl Slobodian ◽

Denys Bykiv ◽

Mykola Pidgurskyi

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Strain State ◽

Analytical Calculation ◽

Complex Stress ◽

The Finite Element Method ◽

Stress Strain ◽

Advantages And Disadvantages ◽

Stress Strain State ◽

Element Method

This article is devoted to evaluating the effectiveness of I-beams with different web perforations: hexagonal, round, oval and elliptical. The technology of manufacturing of castellated beams is described. For the purpose of verification the analytical calculation of the beam with hexagonal web perforation and for comparison the calculation by the finite element method is given. To correctly assess the stress-strain state, the mesh of finite elements in the area of openings was concentrated. The results of maximum normal stresses and strains obtained by different methods were compared with each other and the efficiency of using the finite element method to determine the stress-strain state of castellated beams was proved. In the castellated beams there is a complex stress-strain state, which was confirmed in this work for the most characteristic shapes of openings. Beams with hexagonal, round, oval (horizontal and vertical), elliptical and elliptical (rotated by 45°) openings are considered in the article, their geometric parameters and characteristics as well as advantages and disadvantages are described. Beams with round openings are currently the most widely used. In addition, the parameters that affect the efficiency of castellated beams with oval (horizontal and vertical) and elliptical rotated by 45° openings were identified. In this work, it was found that the shape of the openings significantly affects the stress-strain state of the castellated beams, especially for hexagonal openings, which are mainly used so far. The stress distribution in the first opening for each of the considered types of perforations and the nature of the change of σmax in other openings is shown. The stress-strain state of castellated beams was studied using the finite element method. The results of this study are of practical value because they can be used when arranging the sections and openings of castellated beams.

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Stress-strain state of a three-layer rod. Comparison of the results of analytical and numerical calculations with the experiment

MATEC Web of Conferences ◽

10.1051/matecconf/201819601057 ◽

2018 ◽

Vol 196 ◽

pp. 01057 ◽

Cited By ~ 4

Author(s):

Nikita Tsybin ◽

Robert Turusov ◽

Vladimir Andreev ◽

Alexey Kolesnikov

Keyword(s):

Strain State ◽

Analytical Calculation ◽

Contact Layer ◽

Elastic Rods ◽

Stress Strain ◽

Anisotropic Elastic Medium ◽

Tangential Stresses ◽

Stress Strain State ◽

Anisotropic Elastic ◽

Comparison Of The Results

The article deals with the stress-strain state of a three-layer rod under central compression. The results of analytical calculation and numerical calculation (FEM) are compared with experimental data. It is assumed that the interaction of layers is accomplished through a contact layer. The contact layer is considered as a transversally anisotropic elastic medium with such parameters that it can be represented as a set of short elastic rods that are not connected to each other and are normally oriented to the contact surface. Such an assumption allows us to obtain an analytical solution of the problem in a closed form, as well as to avoid infinite tangential stresses at the interface of the layers near the model end. The obtained results of calculations coincide qualitatively and quantitatively with the results of the experiment.

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INVESTIGATION OF PERMANENT STRAINS IN NANOMODIFIED COMPOSITES AFTER MOLDING AT ELEVATED TEMPERATURES

Periódico Tchê Química ◽

10.52571/ptq.v17.n34.2020.1087_p34_pgs_1055_1073.pdf ◽

2020 ◽

Vol 17 (34) ◽

pp. 1055-1073 ◽

Cited By ~ 3

Author(s):

Arseniy V BABAYTSEV ◽

Ekaterina L KUZNETSOVA ◽

Lev N RABINSKIY ◽

Olga V TUSHAVINA

Keyword(s):

Residual Stress ◽

Strain State ◽

Analytical Calculation ◽

Experimental Result ◽

Stress Strain ◽

Stress Strain State ◽

Binding Material ◽

Power Load ◽

Temperature Load ◽

Residual Strains

This work investigates the effect of carbon nanomodification on the residual stress-strain state (SSS) after molding. One of the ways to reduce residual stresses and deformities is nanomodification. The main objective was to determine the degree of influence of the nanomodification parameters on the residual SSS. Within the framework of this study, 4 slabs were made. Two slabs are made of a conventional binder with laying [010/9010] and [010/4510] and two slabs of a modified binding material with the same layer structure. For the fabricated plates, deflections were measured on each of the four sides, during which residual strains were obtained in the panels of nanomodified carbon fiber for the considered layings with and without modified binding material. To analyze the residual stress-strain state, a numerical and analytical calculation was performed. The numerical calculation was carried out by means of the finite element method for the case when the slab is fixed at the point of the geometric center, with no power load, and the temperature load is a difference of 100 °C. An analytical calculation was carried out for the case when the slab is free from fastening and external power load, and the temperature load is a difference of 100°C. During the study, variants of the physicomechanical properties of the monolayer were obtained using the Digimat software and the Mori-Tanaka averaging method. The results obtained by analytical and numerical methods have a good correlation between each other, and in the course of comparison with the experiment, a method for calculating the characteristics of the monolayer that was closest to the experimental result was determined. On the basis of the obtained results, conclusions were made on the possibility of reducing residual SSS and deformation in structures with asymmetric reinforcement schemes using a matrix containing carbon nanoparticles.

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RESEARCH OF INFLUENCE OF UNFINISHED CONSTRUCTION EXCAVATION ON STRESS-STRAIN STATE OF EXPLOITED BUILDING BEARING STRUCTURES

Building constructions. Theory and Practice ◽

10.32347/2522-4182.2.2018.3-12 ◽

2018 ◽

Vol 0 (2) ◽

pp. 3-12

Author(s):

A Banakh

Keyword(s):

Strain State ◽

Stress Strain ◽

Stress Strain State

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КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ ОСОБЛИВОСТІ ХВОСТО-ВИХ БАЛОК СІТЧАСТОГО ТИПУ З ПОЛІМЕРНИХ КОМПО-ЗИЦІЙНИХ МАТЕРІАЛІВ ВЕРТОЛЬОТІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ

Open Information and Computer Integrated Technologies ◽

10.32620/oikit.2020.88.02 ◽

2020 ◽

pp. 15-30

Author(s):

А. Г. Гребеников ◽

И. В. Малков ◽

В. А. Урбанович ◽

Н. И. Москаленко ◽

Д. С. Колодийчик

Keyword(s):

Finite Element ◽

Strain State ◽

Layer Structure ◽

Metal Structure ◽

Element Model ◽

Stress Strain ◽

Element Analysis ◽

Mesh Structure ◽

Stress Strain State ◽

Mesh Structures

The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.

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