scholarly journals Bending by explosion of a multilayered concrete beam on a visco-elastic basis

2019 ◽  
Vol 97 ◽  
pp. 04055 ◽  
Author(s):  
Yury Nemirovskii ◽  
Sergey Tikhonov
Keyword(s):  
Dynamic Loading ◽  
Cross Section ◽  
Concrete Beam ◽  
Explosive Loading ◽  
Arbitrary Cross Section ◽  
Bending Moments ◽  
Residual Deflection ◽  
Tension And Compression ◽  
The Cross ◽  
Elastic Basis

In this work, the problem of bending of a multilayered concrete beam of arbitrary cross-section by explosive loading on a visco-elastic basis is considered. It is assumed that different grades of concrete can be realized in layers in the cross-section. The property of concrete resistance to tension and compression is considered in work. It is assumed that the dynamic loading is caused by consecutive explosion of two charges over the middle of the span of beam. The distribution of bending moments and deflections of the beam at each time is determined. The time of the end of motion and the residual deflection of beam are found.

scholarly journals Features for calculating beams with a thin transverse corrugated web plate considering bending-twisting forces

2021 ◽  
Vol 263 ◽  
pp. 03006
Author(s):  
Nikolay Tishkov ◽  
Anatoliy Stepanenko
Keyword(s):  
Cross Section ◽  
Numerical Experiments ◽  
Longitudinal Direction ◽  
Arbitrary Cross Section ◽  
Elastic Rods ◽  
Bending Moments ◽  
Relative Height ◽  
Corrugated Web ◽  
Working Together ◽  
The Web

The article describes the features of the work of beams with a thin transverse corrugated web plate. Exponential fractional regression is presented, which allows one to estimate the relative height of web plate sections working together with flanges, obtained by the authors based on an analysis of numerical experiments. Based on the features of the work, a method is proposed for describing the stress state of an arbitrary cross-section of an I-beam with a thin transverse corrugated web plate (the profile of the corrugations is triangular, trapezoidal, sinusoidal) bent in the plane of the web plate and compressed in the longitudinal direction, using the theory of thin-web platted elastic rods by Professor V.Z. Vlasov. The calculations are given for determining the bending-twisting forces (local bending moments and bimoments arising from the action of the main forces) in an arbitrary cross section.

scholarly journals GENERAL CASE OF REINFORCED CONCRETE ROD ELEMENTS CALCULATION USING THE DIAGRAM METHOD

2021 ◽  
Vol 93 (1) ◽  
pp. 26-37
Author(s):  
O.V. RADAYKIN ◽  
◽  
L.S. SABITOV ◽  
L.SH. AKHTYAMOVA ◽  
T.P. ARAKCHEEV ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Longitudinal Force ◽  
Internal Force ◽  
The Other ◽  
Bending Moments ◽  
Diagram Method ◽  
The Cross ◽  
Three Components

In SP 63.13330 the general calculation case for the diagram method is oblique off-center compression, which takes into account only three components of internal force factors in the cross section: the longitudinal force-Nz – and two bending moments relative to the corresponding axes – Mx and My. The other three components-the QX and Qy transfer forces and the MZ torque – are left out of consideration. In addition, for this case, the search in the available literature, including the founders of the diagram method, for the output of calculation formulas was not successful – in all sources they are given in ready-made form without evidence. This article is intended to try to fill in these gaps. For this purpose, based on the expressions for rod displacements that are generally accepted in mechanics, in particular on the Mora integral of displacements, the resolving expressions of the diagram method are obtained in the most general form.

scholarly journals Complex bend of multilayered concrete rods

2019 ◽  
Vol 221 ◽  
pp. 01048
Author(s):  
Yuri Nemirovskii ◽  
Sergey Tikhonov
Keyword(s):  
Small Parameter ◽  
Cross Section ◽  
Arbitrary Shape ◽  
Solution Method ◽  
Parameter Method ◽  
Layer By Layer ◽  
Constant Cross Section ◽  
Bending Moments ◽  
Small Parameter Method ◽  
The Cross

The problem of complex bend of multilayered rods based on concrete is considered. It is assumed that the rod of constant cross-section is of arbitrary shape and different brands of concrete are used in the cross-section of the rod layer by layer. The solution is sought by the small parameter method. The case of a complex bend of the rod pinched at both ends is considered as an example of this solution method. The distribution of bending moments and longitudinal forces in the zero and first approximations is determined.

Herschel-Bulkley Viscoplastic Flow in Tubes of Non-Circular Cross-Section

2016 ◽  
Author(s):  
Mario F. Letelier ◽  
Dennis A. Siginer ◽  
Felipe Godoy ◽  
César Rosas
Keyword(s):  
Cross Section ◽  
Power Index ◽  
Circular Cross Section ◽  
Shear Thickening ◽  
Shear Thinning ◽  
Equation Of Motion ◽  
Arbitrary Cross Section ◽  
Viscoplastic Flow ◽  
The Cross ◽  
Tube Geometry

Flow of a Herschel-Bulkley (H-B) fluid in tubes of non-circular cross-section in investigated analytically. This study complements results presented in [1] where the equation of motion was solved in tubes of arbitrary cross-section for Bingham type of fluids, and the shapes of plug zones centered on the tube axis and stagnant zones attached to the corners were predicted when the cross-section is triangular and square. In this paper we investigate the effect of the power index in the H-B model on the flow for values greater and lesser than unity, considering thus the shear-thinning and shear-thickening effects, which could not be accounted for with the Bingham model. The equation of motion is solved when the cross-section is an equilateral triangle or a square by means of the shape factor method previously introduced in [2]. Thus, shear-thickening and shear-thinning effects are accounted for and related to the tube geometry in predicting the existence and the extent of undeformed regions in the flow field.

Combined Bending and Compression of a Pressurized Circular Cylindrical Membrane Column

1965 ◽  
Vol 87 (3) ◽  
pp. 372-378
Author(s):  
W. E. Jahsman
Keyword(s):  
Compressive Strength ◽  
Cross Section ◽  
Compressive Load ◽  
Circular Cross Section ◽  
Bending Moment ◽  
Maximum Load ◽  
Bending Moments ◽  
Lateral Deflection ◽  
The Cross

Load-lateral deflection curves are developed for a pressurized tube of circular cross section under combined bending and compression. The tube walls are assumed to have negligible compressive strength so that wrinkling develops if the stress tends to become negative. It is found that for a given bending moment, the load increases monotonically with deflection until a maximum is reached beyond which the load decreases with increasing deflection. An interaction curve of the maximum load versus bending moment shows that the presence of only a small amount of bending significantly decreases the maximum compressive load below the classical Euler load. Conversely, for bending moments which produce almost complete wrinkling of the cross section, only very small amounts of compressive load can be supported.

The General Theory of Cylindrical and Conical Tubes under Torsion and Bending Loads

1947 ◽  
Vol 51 (441) ◽  
pp. 757-784 ◽  
Author(s):  
J. Hadji-Argyris ◽  
P. C. Dunne
Keyword(s):  
General Theory ◽  
Cross Section ◽  
Arbitrary Cross Section ◽  
Arbitrary Loading ◽  
Cylindrical Tubes ◽  
Bending Loads ◽  
The Cross ◽  
Distribution Of Stress ◽  
As If

SummaryPart 5 continues the theory given in Parts 1–4 in the February 1947 issue of the Journal (pp. 199–269). The present paper deals with the stresses and deformations of conical and cylindrical tubes under arbitrary loading, thus completing the analysis given in Part 4 which dealt only with pure torque.A remarkable unification of the theory of bending and torsion is achieved. It is shown that the axial constraint stresses, i.e. the corrections to the engineers' stresses, may in general be calculated as if caused by torque about axes different in each mode. The analysis proves that it is in no circumstances correct to calculate the axial constraint stresses from the torque about the flexural axis.Functions giving the cross-wise distribution of stress are fully worked out for the n-boom tube of arbitrary cross-section and for the singly symmetrical trapezoidal tube with continuous direct stress-carrying covers. The analysis is a considerable extension of the results given for the four-boom tube in Part 4.

Material tailoring in functionally graded rods under torsion

2014 ◽  
Vol 228 (18) ◽  
pp. 3283-3295 ◽  
Author(s):  
F Liaghat ◽  
MR Hematiyan ◽  
A Khosravifard
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Torsional Rigidity ◽  
Optimization Methods ◽  
Arbitrary Cross Section ◽  
Functionally Graded ◽  
Material Tailoring ◽  
Graded Material ◽  
The Cross ◽  
Torsional Analysis

Material tailoring in functionally graded isotropic hollow rods of arbitrary cross section under torsion is studied. The purposes of material tailoring pursued in this paper are divided into two categories. In the first category, we find the variation of the volume fractions of constituents of a functionally graded member under torsion to obtain an appropriate distribution of shear stress over the cross section. In the second category, the torsional rigidity of a rod with a pre-defined mass is maximized by appropriate determination of the variation of constituents of the functionally graded material. Hollow rods are studied in this paper since they have higher torsional rigidity compared to solid members with the same mass. Meshless numerical methods are used for torsional analysis of the cross sections. Moreover, numerical optimization methods are used for material tailoring of the rods. Several examples with different cross sections are presented to investigate the usefulness of the proposed technique on achieving the mentioned purposes.

The Fibre Composite Helicopter Blade

1979 ◽  
Vol 30 (2) ◽  
pp. 413-449 ◽  
Author(s):  
E.H. Mansfield ◽  
A.J. Sobey
Keyword(s):  
Cross Section ◽  
Fibre Composite ◽  
Cylindrical Tube ◽  
Arbitrary Cross Section ◽  
Bending Moments ◽  
Engineering Analysis ◽  
Helicopter Blade ◽  
Aeroelastic Tailoring ◽  
Circumferential Distribution ◽  
Stiffness Characteristics

SummaryIn Part 1 expressions are derived for the coupled torsional, extensional and flexural stiffnesses of a fibre composite tube, such as a helicopter blade, which is subjected to torsion, longitudinal tension, chordwise and flapping bending moments and shear. The theory is an extension of Batho-Bredt engineering analysis and is valid for a cylindrical tube of arbitrary cross-section with an arbitrary circumferential distribution of fibre composite plies. Particular attention is paid to the coupling effects in which an asymmetric fibre lay-up results in a twisting of the tube under bending and/or tension. Consideration is also given to the influence on the stiffness characteristics of an initial twist in the tube.In Part 2 the analysis of Part 1 is developed numerically for tubes representative of GFRP blades. Static and dynamic aspects are considered which pave the way for aeroelastic tailoring studies of such blades.

scholarly journals Shear Lag Analysis due to Flexure of Prismatic Beams with Arbitrary Cross-Sections by FEM

2021 ◽  
Author(s):  
Dang-Bao Tran ◽  
Jaroslav Navrátil
Keyword(s):  
Numerical Method ◽  
Cross Section ◽  
Cross Sections ◽  
Arbitrary Cross Section ◽  
Local Analysis ◽  
3D Analysis ◽  
Shear Lag ◽  
Isoparametric Element ◽  
Cross Sectional ◽  
The Cross

This paper presents the use of a finite element method (FEM) to analyze the shear lag effect due to the flexure of beams with an arbitrary cross-section and homogeneous elastic material. Beams are constrained by the most common types of supports, such as fixed, pinned, and roller. The transverse, concentrated, or distributed loads act on the beams through the shear center of the cross-section. The presented FEM transforms the 3D analysis of the shear lag phenomenon into separated 2D cross-sectional and 1D beam modeling. The characteristics of the cross-section are firstly derived from 2D FEM, which uses a 9-node isoparametric element. Then, a 1D FEM, which uses a linear isoparametric element, is developed to compute the deflection, rotation angle, bending warping parameter, and stress resultants. Finally, the stress field is obtained from the local analysis on the 2D-cross section. A MATLAB program is executed to validate the numerical method. The validation examples have proven the efficiency and reliability of the numerical method for analyzing shear lag flexure, which is a common problem in structural design.

scholarly journals Optimization of the parameters of truss beams with two posts

2021 ◽  
Vol 48 (3) ◽  
pp. 117-132
Author(s):  
A. K. Yusupov ◽  
H. M. Musеlеmov, ◽  
T. O. Ustarhanov
Keyword(s):  
Cross Section ◽  
Optimal Parameter ◽  
Bending Moment ◽  
Internal Force ◽  
Numerical Calculations ◽  
Design Parameters ◽  
Bending Moments ◽  
The Cross ◽  
Theoretical Results

Based on the theoretical results obtained in the article [17], here the analysis of the influence of various design parameters on the own weight and cost of metal of truss beams with two posts is carried out. An optimal parameter has been obtained that makes it possible to reduce the calculated bending moment in the cross section of a truss beam with two struts.Method. By equalizing the bending moments in various design sections of the truss beam, the internal force factors are reduced. The corresponding equation for optimizing the parameters of the beam has been drawn up and a formula has been obtained to determine the optimal parameter of the structure as a whole.Result. Using the example of numerical calculations, a decrease in the calculated bending moment by 14% compared to truss beams without optimization is shown.Conclusion. The proposed method and algorithm testify to the efficiency and rationality of the obtained optimal parameter of the structure as a whole.

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