Comparative calculation of optimal parameters of channel bent and bent closed profiles

Relevance. A new technical solution for channel bent closed profiles (BCP), distinguished by a composite section and related to light steel thin-walled structures (LSTWS), which are distinguished by high technical and economic indicators and massive demand in industrial and civil construction, is presented. The main results of the comparative calculation of the optimal parameters of bent channels and channel horizontal bending sections are also given. Aim of the research. The purpose of the study is to show that the characteristics of LSTWS can be further improved by shaping modification profiles, combining in its composite section straight and round outlines of closed and open loops. Methods. Through experimental design and optimization and design calculations of channel profiles, their new technical solution has been developed, the originality of which is confirmed by patent examination. Results. Channel BCP consists of two tubular shelves and one wall of double thickness. For its manufacture without welded, bolted or riveted joints, the outer and inner blanks are made along the entire length with serrated longitudinal edges, the teeth of which are staggered relative to each other and mutually bent in grooves after closing a bent profile along its shelves. The bends of the gear mounts increase the collapse thickness, provide an increase in local stability and shear strength of the thin-walled elements, and also allow not to reduce the design sections. A comparative calculation of the optimal parameters of bent channels and channel bending sections for bending showed that in the first of them the strength is maximum when the ratio of the width and height of the cross section is 1/6, and in the second - 1/5.68.

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I-shaped bent closed profiles with tubular shelves and calculation of the optimal layout of their composite sections

Structural Mechanics of Engineering Constructions and Buildings ◽

10.22363/1815-5235-2020-16-5-334-350 ◽

2020 ◽

Vol 16 (5) ◽

pp. 334-350

Author(s):

Alexander S. Marutyan

Keyword(s):

Technical Solution ◽

Optimal Layout ◽

Design And Optimization ◽

Thin Walled Structures ◽

Riveted Joints ◽

Composite Section ◽

Outer Pair ◽

Thin Walled ◽

Design Calculations ◽

Technical And Economic Indicators

I-shaped bent closed profiles with tubular shelves are distinguished by a composite section and related to light steel thin-walled structures (LSTWS), which are characterized by high technical and economic indicators and mass demand in industrial and civil construction, which determines the relevance of the development of their new technical solutions. The aim of the work - to show that the characteristics of LSTWS can be further improved by forming profiles, combining straight and round outlines of closed and open circuits in a composite section. Methods. New technical solution, the originality of which is confirmed by patent examination, has been developed through experimental design and optimization and design calculations of I-shaped profiles. The calculation of the optimal bending layout of the composite sections of I-shaped profiles of horizontal billets from sheet blanks, identical and unequal in thickness, including bisteel modifications, is made. Results. The I-shaped bent closed profiles consists of two tubular shelves and one wall of double thickness. For its manufacture without welded, bolted or riveted joints, the outer pair and inner pair blanks are made along the entire length with serrated longitudinal edges, the teeth of which are staggered relative to each other and mutually bent in grooves after closing a bent profile along its shelves. The bends of the gear mounts increase the collapse thickness, provide an increase in the local stability and shear strength of the thin-walled elements, and also allow not to reduce the design sections. The calculation of the optimal layout of I-shaped profiles horizontal bend for bending showed that its strength is maximum when the ratio of the width and height of 1/5.2 and equal thicknesses of shelves and walls.

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Curved closed profiles and calculation of their optimal parameters

Structural Mechanics of Engineering Constructions and Buildings ◽

10.22363/1815-5235-2019-15-1-33-43 ◽

2019 ◽

Vol 15 (1) ◽

pp. 33-43

Author(s):

Alexander S Marutyan

Keyword(s):

Shear Strength ◽

Technical Solution ◽

Developmental Studies ◽

Optimal Parameters ◽

Thin Walled Structures ◽

Riveted Joints ◽

Thin Walled ◽

Design Calculations ◽

Technical And Economic Indicators ◽

Patent Examination

Relevance. A new technical solution of bent-closed profiles relating to light steel thin-walled structures (LSTS), which have high technical and economic indicators and are widely used in industrial and civil construction, is presented. Aim of the research. The characteristics of thin-walled structures can be further enhanced by shaping the modification of profiles, combining in its composition the outlines of closed and open outlines. Methods. By means of developmental studies and optimization and design calculations for bent-closed profiles, their new technical solution was developed, the originality of which was confirmed by patent examination. Results. New curved closed profiles (CCP) consist of a tubular part of a single thickness and a double-thickness rib. For their manufacture without welded, bolted or riveted joints, the sheet blank is made along the entire length with serrated longitudinal edges, the teeth of which are arranged relative to each other in a staggered manner and mutually bent in grooves between themselves after the curved profile is closed along its edge. The bends of the gear fasteners increase the thickness of the collapse and provide an increase in the shear strength of the joints of thin-walled elements. With equal dimensions in height and width of the CCP, they are optimized by the criterion of uniform stability, which is the same from the plane and in the plane of the supporting structure. Additionally, a series of pentagonal, triangular and trapezoidal profiles are presen- ted, in which the lateral faces are inclined relative to the vertical at angles of 45 and 60 degrees.

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Optimization of flat-oval pipes and perspectives of their application in beam structures

MATEC Web of Conferences ◽

10.1051/matecconf/201825103016 ◽

2018 ◽

Vol 251 ◽

pp. 03016

Author(s):

Alexander Marutyan ◽

Tamazi Kobaliya ◽

Evgeny Galdin

Keyword(s):

Cross Sections ◽

Bending Strength ◽

Low Cost ◽

Design Parameters ◽

Technical Solution ◽

Optimal Parameters ◽

Resistance Moment ◽

Thin Walled ◽

Lower Height ◽

Oval Shape

A new technical solution for re-profiling round tubes into flat-oval ones with a ratio of 1 / 3,064 is presented, which increases their bending strength. The calculation of the optimal parameters of thin-walled sections of the flat-oval shape is given by an approximate method, the correctness of which is confirmed by testing from the standard profiles used. This calculation is repeated with respect to thin-walled sections of the oval shape. The whole diagram of changes in the design parameters of flat-oval and oval pipes is presented in the transformation of their cross-sections from vertical configurations to horizontal ones, including the transition through the outline of a circular shape. The comparative analysis of optimized cross sections of flat oval, oval and round tubes is carried out taking into account the elastic and elastic-plastic deformations of the structural material, where the length of the midline of the thin-walled section is taken as the dividing line between these deformations. The choice is substantiated in favour of flat-oval profile pipes due to their simpler shape including faces of constant curvature (flat and semi-circular), relatively low cost, lower height, greater compactness, higher resistance moment.

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Numeric simulations of surface pressure and microslip phenomena occurring in riveted joints of semi-monococque structures in effect of the action of tension field

Advanced Technologies in Mechanics ◽

10.17814/atim.2016.1(6).34 ◽

2017 ◽

Vol 3 (1(6)) ◽

pp. 7

Author(s):

Jarosław Mańkowski

Keyword(s):

Thin Plate ◽

Surface Pressure ◽

Test Sample ◽

Thin Walled Structures ◽

Material Deformation ◽

Riveted Joints ◽

Thin Walled

Tension fields are shown to have an influence on surface pressure and on material deformation in the riveted joints in thin walled structures and particularly in semistressed skin structures. Stresses and materials displacements were analyzed in the riveted joints performing under such conditions. Special attention has been attached to estimation of the microslips occurring between rivets and holes. A thin plate panel has been used for the test sample, which under effort condition revealed tension fields.

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The in situ ply elasticity and strength in laminated composites

Engineering Journal Science and Innovation ◽

10.18698/2308-6033-2020-7-1996 ◽

2020 ◽

Author(s):

A.I. Oleinikov ◽

T.A. Kuzmina

Keyword(s):

Strength Characteristics ◽

Compression Tests ◽

Thin Walled Structures ◽

Calculation Results ◽

Working Together ◽

Real Behavior ◽

Thin Walled ◽

Design Calculations ◽

Direct Tensile

When calculating thin-walled structures made of layered polymer composite materials (PCM), data obtained as data obtained from testing a corresponding separately cured unidirectional sheet is accepted as the elastic-strength characteristics of their monolayers. Properties of such sheet significantly differ from the characteristics of the monolayer polymerized and working together with adjacent layers of different orientations as part of a composite package. The article presents the results of solving the problem of determining the elastic and strength characteristics of monolayers according to the data of direct tensile — compression tests of PCM samples from witness parts. It considers PCM which monolayers have similar or diverse characteristics. Formulas are given for calculating the mechanical properties of monolayers as part of a multidirectional composite package. Comparison of calculation results with test data is carried out. The use of the actual characteristics of monolayers makes it possible to calculate the real behavior of the PCM in the structure, to link its verification and design calculations.

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CONCEALED FRAME MADE OF LIGHT STEEL THIN-WALLED STRUCTURES IN MONOLITHIC FOAM CONCRETE

Scientific Papers Collection of the Angarsk State Technical University ◽

10.36629/2686-7788-2021-1-1-134-137 ◽

2021 ◽

Vol 2021 (1) ◽

pp. 134-137

Author(s):

Andrey Savenkov ◽

Evgeniy Zaenec ◽

Andrey Ketner

Keyword(s):

Technical Solution ◽

Foam Concrete ◽

Standard Version ◽

Thin Walled Structures ◽

Overall Stability ◽

Thin Walled

The use of buildings frame elements formed from thin-walled unclosed profiles located in a monolith-ic foam concrete array is considered. This technical solution provides a number of advantages in comparison with the standard version of metal frames, including increasing the overall stability of lightweight profiles

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