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1 – 10 of over 5000Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…
Abstract
Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.
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A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical…
Abstract
A bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view is given. The bibliography at the end of the paper contains 1,726 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1996‐1999.
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Angelo Vumiliya, Ani Luo, Heping Liu and Andrés González
This paper aims to propose a study on the static behavior of prismatic tensegrity structures and an innovative form for determining the effect of mechanical properties and…
Abstract
Purpose
This paper aims to propose a study on the static behavior of prismatic tensegrity structures and an innovative form for determining the effect of mechanical properties and geometric parameters on the minimal mass design of these structures.
Design/methodology/approach
The minimal mass design in this paper considers a stable class-two tensegrity tower built through stable models. Using the proposed structures, comprehensive parametric studies are performed to examine the mass (in which the masses of joints are ignored), the mass ratio between a class-two tensegrity tower and a single element, both having the same diameter and length and afterward determine a reliable mass saving structure under various circumstances.
Findings
The simulations show that the mass ratio versus the number of units is a nonlinear regressive curve and predicts that the proposed model outperforms the standard model when the variation parameter considered is a vertical force. The difference in mass between these structures is visible when the gap gradually decreases while the number of units increases. On the geometrical aspect, the gap between the masses is not significant.
Originality/value
This paper helps to understand the influences of geometric parameters and the mechanical properties on the design of cylinder tensegrity structures dealing with a compressive force.
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Rabe Alsafadie, Mohammed Hjiaj, Hugues Somja and Jean‐Marc Battini
The purpose of this paper is to present eight local elasto‐plastic beam element formulations incorporated into the corotational framework for two‐noded three‐dimensional beams…
Abstract
Purpose
The purpose of this paper is to present eight local elasto‐plastic beam element formulations incorporated into the corotational framework for two‐noded three‐dimensional beams. These formulations capture the warping torsional effects of open cross‐sections and are suitable for the analysis of the nonlinear buckling and post‐buckling of thin‐walled frames with generic cross‐sections. The paper highlights the similarities and discrepancies between the different local element formulations. The primary goal of this study is to compare all the local element formulations in terms of accuracy, efficiency and CPU‐running time.
Design/methodology/approach
The definition of the corotational framework for a two‐noded three‐dimensional beam element is presented, based upon the works of Battini .The definitions of the local element kinematics and displacements shape functions are developed based on both Timoshenko and Bernoulli assumptions, and considering low‐order as well as higher‐order terms in the second‐order approximation of the Green‐Lagrange strains. Element forces interpolations and generalized stress resultant vectors are then presented for both mixed‐based Timoshenko and Bernoulli formulations. Subsequently, the local internal force vector and tangent stiffness matrix are derived using the principle of virtual work for displacement‐based elements and the two‐field Hellinger‐Reissner assumed stress variational principle for mixed‐based formulations, respectively. A full comparison and assessment of the different local element models are performed by means of several numerical examples.
Findings
In this study, it is shown that the higher order elements are more accurate than the low‐order ones, and that the use of the higher order mixed‐based Bernoulli element seems to require the least number of FEs to accurately model the structural behavior, and therefore allows some reduction of the CPU time compared to the other converged solutions; where a larger number of elements are needed to efficiently discretize the structure.
Originality/value
The paper reports computation times for each model in order to assess their relative efficiency. The effect of the numbers of Gauss points along the element length and within the cross‐section are also investigated.
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In 1933, Edward H. Chamberlin published the Theory of Monopolistic Competition (1962). The work, based upon a dissertation submitted for a PhD degree in Harvard University in 1927…
Abstract
In 1933, Edward H. Chamberlin published the Theory of Monopolistic Competition (1962). The work, based upon a dissertation submitted for a PhD degree in Harvard University in 1927 and awarded the David A. Wells prize for 1927–28, has since become a milestone in the development of economic thought. Its impact on industrial organisation theory, general equilibrium and welfare economics, international trade theory and, to a greater or lesser degree, all other branches of economic analysis, has been pervasive and enduring. The ideas set out in the book have been developed, expanded and refined in ways too numerous to be identified precisely, and the books and articles which take Chamberlin's contribution as a starting point arguably exceed in number those on any other single subject in the lexicon of economics.
Looks at Arrow’s early background in New York and his subsequent development in the field of econometrics and mathematical economics. Covers his work in depth and his achievements…
Abstract
Looks at Arrow’s early background in New York and his subsequent development in the field of econometrics and mathematical economics. Covers his work in depth and his achievements in the school of thought of economics, adding that the modern school of thought is complementary to the classical school.
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Lothar Haefner and Kaspar J. Willam
A simple beam element is developed for the solution of large deflection problems. The total Lagrangian formulation is based on the kinematic relations proposed by Reissner for…
Abstract
A simple beam element is developed for the solution of large deflection problems. The total Lagrangian formulation is based on the kinematic relations proposed by Reissner for finite rotations and stretching as well as shearing of plane beams. The motion is discretized by linear expansions of the global displacement components and the cross‐sectional rotation in two‐dimensional Euclidean space yielding a simple beam element with three degrees of freedom at the two nodes. The shear locking is reduced by selective integration in order to eliminate the spurious shear constraint similar to interdependent variable interpolation. The large rotation formulation is compared with two forms of moderate rotation theories which have been used in the past to develop the geometric stiffness properties for linear stability analysis of the so‐called Mindlin plate elements. The predictive value of different geometric stiffness approximations is assessed with several examples which range from the static and kinetic stability analysis of the classical Euler‐column to the large deflection problem of a clamped beam.
P. Krawczyk, F. Frey and A.P. Zieliński
This paper aims to present development of a layer‐wise (LW) beam model for geometric nonlinear finite element analysis of laminated beams with partial layer interaction.
Abstract
Purpose
This paper aims to present development of a layer‐wise (LW) beam model for geometric nonlinear finite element analysis of laminated beams with partial layer interaction.
Design/methodology/approach
The model is built assuming first order shear deformation theory (FSDT) at layer level and moderate interlayer slips. LW kinematic, strain and stress fields are established in view of co‐rotational finite element formulation. Laminated beam equilibrium relations are developed in strong, weak and matrix form. A notion of interface shear stress is used to define layer interactions.
Findings
Through suitable choice of kinematic model the co‐rotational approach is shown to provide means of obtaining robust finite element formulation for geometric nonlinear analysis of laminated structures with interlayer slips.
Research limitations/implications
The proposed model is dedicated to geometric nonlinear finite element analysis of laminated beams undergoing large planar displacements, subject to small strains and moderate interlayer slips.
Originality/value
Novelty of the proposed approach is based on encompassing shear deformations in geometric nonlinear analysis of laminated beams with interlayer slips. Arbitrary number of layers is considered.
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Yabo Guan, Farhang Pourboghrat and Woong‐Ryeol Yu
The purpose of this paper is to provide an axisymmetric model of tube hydroforming using a Fourier Series based finite element method.
Abstract
Purpose
The purpose of this paper is to provide an axisymmetric model of tube hydroforming using a Fourier Series based finite element method.
Design/methodology/approach
Fourier series interpolation function, which considerably reduces the size of the global stiffness matrix and the number of variables, is employed to approximate displacements. The material of the tube is assumed to be elastic‐plastic and to satisfy the plasticity model that takes into account the rate independent work hardening and normal anisotropy. Numerical solution obtained from an updated Lagrangian formulation of the general shell theory is employed. The axial displacement stroke (a.k.a. axial feed) during tube hydroforming is incorporated using Lagrange multipliers. Contact constraints and boundary friction condition are introduced into the formulation based on the penalty function, which imposes the constraints directly into the tangent stiffness matrix. A forming limit curve based on shear instability and experimental measurements are used as fracture criteria.
Findings
The results obtained from this new formulation are compared against the nonlinear finite element code ABAQUS and experimental measurements for isotropic and transversely anisotropic tube materials. The hoop and axial strains predicted with AXHD code compared excellently with those from ABAQUS FEM code using plane stress axisymmetric (SAX1) and four‐node shell (S4R) elements. However, in the case of aluminum, the numerically predicted maximum hoop strain underestimated the actual hoop strain measured from the tube bulging experiment.
Practical implications
The axisymmetric hydroforming program (AXHD) developed in this work is very efficient in simulating the free‐forming stage of the tube hydroforming process under simultaneous action of internal pressurization and displacement stroke.
Originality/value
Although Fourier Series based finite element method has been used in metal forming, the extended application presented in this paper is novel in the finite element analysis of tube hydroforming.
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Rubber gaskets find wide applications in steel structures. Gaskets are usually used on the edges or on the nail hole positions. These are the weakest positions, where corrosion…
Abstract
Rubber gaskets find wide applications in steel structures. Gaskets are usually used on the edges or on the nail hole positions. These are the weakest positions, where corrosion starts, whether the structure is protected by paint or by other methods. In this work, anticorrosive pigments were incorporated in rubber formulations. They are tested by corrosion protection when used as gaskets with steel panels. Results showed that the presence of anticorrosive pigments in rubber gaskets prevents early rusting under it in comparison with the blank. Zinc‐tetroxy chromate pigment exhibited the highest rust inhibiting power when chloroprene rubber formulations were used. The change of the pigment percent barely affect the quality of protection when syrenebutadiene rubber formulation were used. Zinc tetroxy chromate pigment improved the physico‐mechanical properties of chloroprene rubber under investigation. The used formulations can tolerate thermal oxidative aging at 90°C up to 8 days. The rate of vulcanization was not affected by increasing the concentration of the inhibitive pitments.