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Article
Publication date: 20 December 2018

Shalini Saha, Amares Chattopadhyay and Abhishek Kumar Singh

The purpose of this paper is to develop a numerical (finite-difference) model exploring phase and group velocities of SH-wave propagation in initially stressed transversely…

Abstract

Purpose

The purpose of this paper is to develop a numerical (finite-difference) model exploring phase and group velocities of SH-wave propagation in initially stressed transversely isotropic poroelastic multi-layered composite structures and initially stressed viscoelastic-dry-sandy multi-layered composite structures in two distinct cases.

Design/methodology/approach

With the aid of relevant constitutive relations, the non-vanishing equations of motions for the propagation SH-wave in the considered composite structures have been derived. Haskell matrix method and finite-difference scheme are adopted to deduce velocity equation for both the cases. Stability analysis for the adopted finite-difference scheme has been carried out and the expressions for phase as well as group velocity in terms of dispersion-parameter and stability-ratio have been deduced.

Findings

Velocity equations are derived for the propagation of SH-wave in both the composite structures. The obtained results are matched with the classical results for the case of double and triple-layered composite structure along with comparative analysis. Stability analysis have been carried out to develop expressions of phase as well as group velocity in terms of dispersion-parameter and stability-ratio. The effect of wavenumber, dispersion parameter along with initial-stress, porosity, sandiness, viscoelasticity, stability ratio, associated with the said composite structures on phase, damped and group velocities of SH-wave has been unveiled.

Originality/value

To the best of authors’ knowledge, numerical modelling and analysis of propagation characteristics of SH-wave in multi-layered initially stressed composite structures composed of transversely isotropic poroelastic materials and viscoelastic-dry-sandy materials remain unattempted inspite of its importance and relevance in many branches of science and engineering.

Details

Engineering Computations, vol. 36 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 5 May 2015

Jun Lin, Hakim Naceur, Daniel Coutellier and Abdel Laksimi

– The purpose of this paper is to present an efficient smoothed particle hydrodynamics (SPH) method particularly adapted for the geometrically nonlinear analysis of structures.

Abstract

Purpose

The purpose of this paper is to present an efficient smoothed particle hydrodynamics (SPH) method particularly adapted for the geometrically nonlinear analysis of structures.

Design/methodology/approach

In order to resolve the inconsistency phenomenon which systematically occurs in the standard SPH method at the domain’s boundaries of the studied structure, the classical kernel function and its spatial derivatives were modified by the use of Taylor series expansion. The well-known tensile instabilities inherent to the Eulerian SPH formulation were attenuated by the use of the Total Lagrangian Formulation (TLF).

Findings

In order to demonstrate the effectiveness of the present improved SPH method, several numerical applications involving geometrically nonlinear behaviors were carried out using the explicit dynamics scheme for the time integration of the PDEs. Comparisons of the obtained results using the present SPH model with analytical reference solutions and with those obtained using ABAQUS finite element (FE) commercial software, show its good accuracy and robustness.

Practical implications

An additional application including a multilayered composite structure and involving buckling and delamination was investigated using the present improved SPH model and the results are compared to the FE results, they confirmed both the efficiency and the accuracy of the proposed method.

Originality/value

An efficient 2D-continuum SPH model for the geometrically nonlinear analysis of thin and thick structures is proposed. Contrarily to the classical SPH approaches, here the constitutive material relations are used to link naturally the stresses and strains. The Total Lagrangian approach is investigated to alleviate the tensile instabilities problem, allowing at the same time to avoid the updating procedure of the neighboring particles search and therefore reducing CPU usage. The proposed approach is valid for isotropic and multilayered composites structures undergoing large transformations. CPU time savings and better results with the new 2D-continuum SPH formulation compared to the classical continuum SPH. The explicit dynamic scheme was used for time integration allowing a fast resolution algorithm even for highly nonlinear problems.

Details

Engineering Computations, vol. 32 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 June 2003

Claudia Herzberg, Sybille Krzywinski and Hartmut Rödel

Complex material requirements for high‐technology applications increasingly demand the use of hybrid material structures with properties tailored to the lines of loading…

Abstract

Complex material requirements for high‐technology applications increasingly demand the use of hybrid material structures with properties tailored to the lines of loading. Textile‐reinforced multilayer composite structures are particularly suitable for the production of component structures in an optimised lightweight construction. In the loading case, however, delaminating phenomena occur between the individual layers due to the low interlaminar shear strength. The appropriate techniques and machines of the ready‐made‐clothing technology allow the specific sewing‐up of the semifinished textile products into a three‐dimensionally reinforced multilayer composite structure; the setting of a load‐adapted and failure‐tolerant characteristic of properties being possible in the z‐direction through a versatile variation of sewing parameters. Moreover, the sewing technology makes possible a ready‐made‐clothing‐technological preassembly of components of semi‐finished products, and thus can perform position‐fixing functions in the consolidation of the composites. The ready‐made‐clothing process is divided into sub‐processes like product development, preparation of cutting, cutting, connecting and forming as well as packaging and shipping. The technical procedures and machines applied are chosen from economic aspects. Besides the large number of pieces, extreme thickness of the textile products of up to 20 mm and the required sewing precision demand precise and reproducible manufacturing processes.

Details

International Journal of Clothing Science and Technology, vol. 15 no. 3/4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 11 September 2017

Victor Rizov

The purpose of this paper is to perform an analytical study of non-linear elastic delamination fracture in the multilayered functionally graded split cantilever beam (SCB…

Abstract

Purpose

The purpose of this paper is to perform an analytical study of non-linear elastic delamination fracture in the multilayered functionally graded split cantilever beam (SCB) configuration. The SCB studied may have an arbitrary number of vertical layers. The material in each layer is functionally graded along the layer thickness. Also, the material properties may be different in each layer. The analytical solution derived was applied for parametric investigations in order to evaluate the effects of material properties and delamination crack location on the non-linear fracture behaviour.

Design/methodology/approach

The delamination fracture was studied in terms of the strain energy release rate. The SCB mechanical response was described by using a power-law stress-strain relation. A non-linear analytical solution for the strain energy release rate was derived by considering the SCB complementary strain energy. In order to verify the solution, an additional analysis of the strain energy release rate was developed by considering the complementary strain energy in the beam cross-sections ahead and behind the crack front.

Findings

The effects of material gradient, crack location along the beam width and non-linear material behaviour on the delamination fracture were evaluated. The analytical solution derived is useful for parametric studies of non-linear fracture in multilayered functionally graded beams.

Originality/value

Delamination fracture in the multilayered functionally graded SCB configuration was analysed with considering the non-linear material behaviour.

Details

Multidiscipline Modeling in Materials and Structures, vol. 13 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 March 1996

Aleksander Muc

Presents a finite element formulation of the layout optimization and design sensitivity applied to doubly‐curved shells of revolution. The objectives of the optimization are to…

Abstract

Presents a finite element formulation of the layout optimization and design sensitivity applied to doubly‐curved shells of revolution. The objectives of the optimization are to maximize buckling pressures and first‐ply‐failure pressures. The problem is formulated and solved with the use of geometrically non‐linear transverse shear shell theory. However, the optimization method proposed limits the sensitivity analysis to a geometrically linear problem. Focuses special attention on the formulation of the optimization problem taking into account various factors, such as the form of geometrical and physical relations, types of design variables and the finite element discretization. Demonstrates several numerical examples to illustrate the capability of the proposed optimization procedures.

Details

Engineering Computations, vol. 13 no. 2/3/4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 14 November 2016

Victor Rizov

The purpose of this paper is to deal with an analytical investigation of delamination fracture in the mixed-mode bending (MMB) multilayer beam configurations taking into account…

Abstract

Purpose

The purpose of this paper is to deal with an analytical investigation of delamination fracture in the mixed-mode bending (MMB) multilayer beam configurations taking into account the material non-linearity.

Design/methodology/approach

The J-integral approach was applied in fracture analysis. The beam layers non-linear mechanical response was described by using a power-law stress-strain relation with four material constants. Analytical solutions of the J-integral were derived by using the technical beam theory. The fracture analysis developed is valid for MMB beams whose layers may have different thicknesses. Also, the values of material constants in the non-linear stress-strain equation may be different for each layer.

Findings

The effect of material constants, crack location and layer thicknesses on the non-linear fracture was evaluated. The analytical solutions obtained are very suitable for parametric studies of non-linear fracture behaviour. The approach developed here can be used for optimization of multilayered beam structures with respect to the delamination fracture performance. The present study can also be useful for the understanding of fracture in multilayered beams exhibiting material non-linearity.

Originality/value

For the first time, an analytical study was performed of the delamination fracture behaviour of the MMB multilayered beam configuration taking into account the material non-linearity.

Details

Multidiscipline Modeling in Materials and Structures, vol. 12 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 12 February 2018

Victor Rizov

This paper aims to analyze the elastic-plastic delamination fracture behaviour of multilayered functionally graded four-point bending beam configuration.

Abstract

Purpose

This paper aims to analyze the elastic-plastic delamination fracture behaviour of multilayered functionally graded four-point bending beam configuration.

Design/methodology/approach

The mechanical response of beam is described by a power-law stress-strain relation. The fracture is studied analytically in terms of the strain energy release rate by considering the beam complimentary strain energy. The beam can have an arbitrary number of layers. Besides, each layer may have different thickness and material properties. Also, in each layer, the material is functionally graded along the beam width. A delamination crack is located arbitrary between layers. Thus, the crack arms have different thickness.

Findings

The analysis developed is used to elucidate the effects of crack location, material gradient and non-linear behaviour of material on the delamination fracture. It is found that the material non-linearity leads to increase in the strain energy release rate. Therefore, the non-linear behaviour of material should be taken into account in fracture mechanics-based safety design of structural members and components made of multilayered functionally graded materials. The analysis revealed that the strain energy release rate can be effectively regulated by using appropriate material gradients in the design stage of multilayered functionally graded constructions.

Originality/value

Delamination fracture behaviour of multilayered functionally graded four-point bending beam configuration is studied in terms of the strain energy release rate by taking into account the material non-linearity.

Details

World Journal of Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Content available
Article
Publication date: 1 March 2006

34

Abstract

Details

Industrial Robot: An International Journal, vol. 33 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 9 January 2007

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.

Details

Engineering Computations, vol. 24 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 21 September 2020

Shishir Gupta, Soumik Das and Rachaita Dutta

The purpose of this paper is to investigate the mathematical model comprising a heterogeneous fluid-saturated fissured porous layer overlying a non-homogeneous anisotropic…

Abstract

Purpose

The purpose of this paper is to investigate the mathematical model comprising a heterogeneous fluid-saturated fissured porous layer overlying a non-homogeneous anisotropic fluid-saturated porous half-space without fissures. The influence of point source on horizontally polarized shear-wave (SH-wave) propagation has been studied intensely.

Design/methodology/approach

Techniques of Green’s function and Fourier transform are applied to acquire displacement components, and with the help of boundary conditions, complex frequency equation has been constructed.

Findings

Complex frequency relation leads to two distinct equations featuring dispersion and attenuation properties of SH-wave in a heterogeneous fissured porous medium. Using MATHEMATICA software, dispersion and damping curves are sketched to disclose the effects of heterogeneity parameters associated with both media, parameters related to rigidity and density of single porous half-space, attenuation coefficient, wave velocity, total porosity, volume fraction of fissures and anisotropy. The fact of obtaining classical Love wave equation by introducing several particular conditions establishes the validation of the considered model.

Originality/value

To the best of the authors’ knowledge, effect of point source on SH-wave propagating in porous layer containing macro as well as micro porosity is not analysed so far, although theory of fissured poroelasticity itself has vast applications in real life and impact of point source not only enhances the importance of fissured porous materials but also opens a new area for future research.

Details

Engineering Computations, vol. 38 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

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