ТЕОРЕТИЧНЕ ДОСЛІДЖЕННЯ НАПРУЖЕНО-ДЕФОРМОВАНОГО СТАНУ БАЗОВИХ ПЛИТ УЗРП-16

Theoretical studies of the stress-strain state of base plates, which are the base of the UZRP-16 universal collapsible machines have been done. These machines are used for welding works in machine building industry. The finite element method was applied to solve the problems. Nature of influence of strength and structural parameters on the base plate stress-strain state in operation has been determined, namely: the relations between displacements and stresses arising in the base plates and the bending moment magnitudes have been recorded; the stress-strain state pattern of the base plates has been obtained depending on the place of bending moment application; influence of the conditions for bearing and fastening the plates on their stress-strain state has been investigated; influence of the plate geometric parameters on stress and displacement has been studied; The stress-material and displacement-material relations have been obtained for the plates. Based on the theoretical study results of the base plate stress-strain state, the following have been obtained: stress plots and patterns of deformed surfaces, which are symmetrical with respect to the plate central axes; maximum values of normal and tangential stress components arising in the field of bending moment application; stress on the rectangular base plate surface is 2.1 times higher than the stress on square plate surface under the same conditions of bearing and loading; stresses acting on the plate surfaces and being tensile stresses within the range of 10 to 70 MPa. It was found that the square shape of the plates, according to the stress state, is predominant in relation to the rectangular shape. The optimal condition for bearing is fixing the plates at nine points. For the first time, graphs were drawn for choosing the base plate thickness under action of various operational loads.

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Stress-strain state of tight joints under a bending moment

Russian Engineering Research ◽

10.3103/s1068798x10080022 ◽

2010 ◽

Vol 30 (8) ◽

pp. 759-762 ◽

Cited By ~ 3

Author(s):

I. V. Abramov ◽

A. I. Abramov ◽

A. N. Sinitsyn ◽

V. V. Sinitsyna

Keyword(s):

Strain State ◽

Bending Moment ◽

Stress Strain ◽

Stress Strain State

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STRESS-STRAIN STATE OF CURVED LAMINATED WOODEN ELEMENTS DURING PRODUCTION

Architecture and Engineering ◽

10.23968/2500-0055-2020-5-4-51-59 ◽

2020 ◽

Vol 5 (4) ◽

pp. 51-59

Author(s):

Alexander Schmidt ◽

Keyword(s):

Strain State ◽

Initial Stresses ◽

Internal Stresses ◽

Shear Stresses ◽

Stress Strain ◽

Stress Strain State ◽

Operational Load ◽

Study Results ◽

The Impact ◽

Wooden Structures

Introduction: The stress-strain state (SSS) of curved laminated wooden elements may differ significantly from the SSS of straight laminated wooden elements, not only in terms of the curvature but also in terms of production specifics and operational load. A curved element is produced by bending wooden planks (lamellae) and gluing them together. In the process, the structure is subjected to initial internal stresses, as the lamellae tend to straighten out again. After production is complete, the element experiences unequal initial internal stresses, which alters its strength properties in different directions in relation to the timber fibers. At a later point, this is going to contribute to the stresses that the structure experiences under external pressure. The Russian and foreign regulations (SP, EuroCode 5, DIN) do not pay sufficient attention to this fact, which has merited this study. Methods: For the aforementioned purpose, we review a mathematical model of the SSS emergence in curved laminated wooden elements. We roughly divide the process into two stages: stage 1 involves bending separate lamellae, gluing them together, and pressing them down; stage 2 involves pressing out the laminated package. This results in prestress, which is a combination of tangential, radial, and shear stresses. Results: Our study results in a visual representation of the total prestress during stages 1 and 2. Such a representation allows for predicting stresses in curved laminated wooden structures under alternating operational loads. Discussion: We highlight the impact of the relaxation of initial stresses, which requires further study. Depending on the direction and amount of operational load, the curved laminated section of a structure may “attempt” to straighten out (i.e. with a decrease in curvature), or may curve even further. This is not properly reflected in the guidelines for wooden structures’ design and needs to be examined further.

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The investigation of the stress-strain state of beam crossings with a truss-form supporting element of the operating pipeline

Prospecting and Development of Oil and Gas Fields ◽

10.31471/1993-9973-2020-3(76)-71-84 ◽

2020 ◽

pp. 71-84

Author(s):

Т. Yu. Pyrih ◽

Ya. V. Doroshenko ◽

Ya. І. Matviichuk

Keyword(s):

Strain State ◽

Bending Moment ◽

Isosceles Triangle ◽

Internal Force ◽

Gas Pipeline ◽

Stress Strain ◽

Scientific Publications ◽

Stress Strain State ◽

Supporting Element ◽

Longitudinal Strains

The areas of application and advantages of the over-ground piping or pipe section layout are given. The classification according to the design features of the most common systems of overhead pipeline crossings on the basis of generalization of scientific publications and experience of pipeline construction are considered. The authors indicate the ranges of the effective spans for rectilinear single-span and multi-span crossings without compensators of longitudinal strains (with the fixed ends) and also in multi-span systems with compensators depending on the diameter of pipes, nominal pipe wall thickness and brand of pipe steel for gas, oil and oil-products pipelines respectively. The description of the design of beam systems of overhead pipeline crossings with a truss-form supporting element of the operating pipeline is given and the procedure for estimating their stress-strain state is suggested. According to the constructed cargo and unit calculation schemes of the truss with a cross-section in the form of an isosceles triangle (height – 3 m, width – 2.02 m) the stiffness coefficients of elastic-malleable supports is determined. The selection of cross-sections of truss members is carried out, the required deflections of the pipeline and the emerging internal force factors (bending moments and reactions of elastic-malleable supports) at the points where the pipeline rests on the truss are found. The strength of the pipeline to the action of the maximum bending moment is checked and the possibility of the cross-water layout of the beam crossing of the gas pipeline is shown. This is the gas pipeline with the length of . It has compensators with a truss-form supporting element which eliminates the use of intermediate supports. Thus, it was shown that the truss makes it possible to double or triple the length of the span using no intermediate supports and preserving sufficient horizontal rigidity.

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Measuring the Temperature and Stress-Strain States of a Tube Sample under the Local Stochastic Temperature Pulsations

Devices and Methods of Measurements ◽

10.21122/2220-9506-2019-10-1-53-60 ◽

2019 ◽

Vol 10 (1) ◽

pp. 53-60

Author(s):

S. M. Dmitriev ◽

R. R. Ryazapov ◽

A. V. Mamaev ◽

A. E. Sobornov ◽

A. V. Kotin ◽

...

Keyword(s):

Temperature Field ◽

Nuclear Power ◽

Strain State ◽

Technical Problem ◽

Coolant Flow ◽

Stress Strain ◽

Spectral Correlation ◽

Stress Strain State ◽

Study Results ◽

Temperature Pulsations

Provding a high level of durability of heat exchange equipment of water-cooled reactors under local stochastic temperature pulsations is an important scientific and technical problem for the nuclear power industry. Temperature pulsations produced by mixing non-isothermal coolant flows with high temperature gradient are most dangerous. This work is an experimental study of temperature and stress-strain state of a tube sample under local stochastic temperature pulsations caused by mixing of coolant flows.To solve the problems posed, aY-junction with «counter injection» was built, which was included in the thermal-hydraulic research facility. The design of theY-junction allows study of the thermal-hydraulic characteristics and durability of tube samples made of austenitic steel of 60 × 5 мм. Some tube samples had developed for measuring the temperature, stress-strain state of tube material and temperature field of coolant flow in mixing zone of single-phase coolants with different temperatures. Measuring tube samples were equipped with micro thermocouples and strain gauges.The experimental data of temperature pulsations, time-averaged temperature field in the coolant flow and on the outer surface of the sample were obtained, and statistical and spectral correlation characteristics of temperature pulsations were analyzed. According to results of measuring the relative strain, values of stresses were calculated.Devices and research techniques are developed. The combination of coolant flows parameters that provide thermal load of the metal surface at the highest level of stress intensity amplitude was obtained. The study results are used to verify the method for evaluating fatigue of reactor installations materials under stochastic temperature pulsations.

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STUDY OF THE INFLUENCE OF KARST PROCESSES ON STRESS-STRAIN STATE OF THE BUILDING FRAME

Construction and Architecture ◽

10.29039/article_5c35edab418059.47946570 ◽

2019 ◽

Vol 6 (4) ◽

pp. 19-23

Author(s):

Галина Кравченко ◽

Galina Kravchenko ◽

Елена Труфанова ◽

Elena Trufanova ◽

Артем Матвейкин ◽

...

Keyword(s):

Strain State ◽

Base Plate ◽

Natural Conditions ◽

Stress Strain ◽

Building Frame ◽

Software Complex ◽

Stress Strain State ◽

The Impact ◽

Karst Processes ◽

Storey Building

The article deals with the natural conditions of the karst, the factors of its development and the impact of this geological process on the stress-strain state of the building frame. In the software complex SCAD developed 10 versions of models of frame-monolithic multi-storey building, taking into account the variation of karst localization. Taking into account the influence of karst processes on the stress-strain state of the frame of the building allowed to calculate the movement of the base plate, depending on the location of the funnel, to identify the greatest movement and choose the reinforcement that provides the necessary strength of the frame of the building in any adverse karst process.

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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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