2,587 research outputs found
Modelling of Damaged Laminated and Sandwich Shell Structures by means of Higher-order Shear Deformation Theories
No full textThe main aim of the current research is the development of a mathematical formulation for the modelling of damage in laminated and sandwich composite shells. For this purpose, the damage of some areas of the structures can be seen as concentrated decays of the mechanical properties of the elastic constituents. In general, several kinds of damage can affect the mechanical behavior of a generic laminated structure, such as microcracking, debonding, fiber ruptures, and transverse matrix cracking, as specified in [1].
Without investigating the causes of the damage, the current approach suggests to introduce peculiar functions that multiply directly the mechanical properties of the elastic media, expressed in terms of engineering constants. To this aim, the Gaussian function and an ellipse shaped law are used to model a quick variation of the mechanical properties within the whole structural domain. By setting properly the parameters that characterize these distributions, it is possible to control the intensity of the deterioration and the width of the damaged areas, as well as the point of applications.
The present approach is employed to characterize the damage in some doubly-curved shells characterized by different radii of curvature. The difficulties related to the description of these curved surfaces are overcome by means of an analytical formulation based on differential geometry [2]. As far as the mechanical properties are concerned, several constituents are considered and combined.
The theoretical framework is based on a formulation that allows to develop easily different kinematic models and expansions in a unified manner. Thus, several Higher-order Shear Deformation Theories, which can include also the zig-zag effect, are employed. In fact, it has been proven that peculiar mechanical configurations require an enriched structural model, since lower-order theories could be inadequate to capture the effective mechanical behavior.
Finally, a numerical technique able to solve the strong form of the governing equations is used. For this purpose, the partial derivatives that appear in the fundamental system are directly approximated through the Generalized Differential Quadrature method due to its accuracy [3].
References
[1] Tornabene, F., Fantuzzi, N., Bacciocchi, M., “Linear Static Behavior of Damaged Laminated Composite Plates and Shells”, Materials, 10, 811, 1-52 (2017).
[2] Tornabene, F., Fantuzzi, N., Bacciocchi, M., and E. Viola, Laminated Composite Doubly-Curved Shell Structures. Differential Geometry. Higher-order Structural Theories, Esculapio, Bologna (2016).
[3] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., “Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey”, Applied Mechanics Reviews, 67, 020801-1-55
Strong and Weak Formulations for the Analysis of Arbitrarily Shaped Laminated Composite Structures
No full textA numerical approach is developed to deal with arbitrarily shaped structures. Two different methodologies are used to this aim, which are based on the Differential Quadrature and Integral Quadrature methods, respectively. These numerical methods are able to approximate both derivatives and integrals [1]. Therefore, the strong and weak formulations of the governing equations can be solved. As shown in the paper [2], these approaches are accurate, reliable and stable, when employed to obtain the mechanical response of various kinds of structures, such as plates, shells and membranes. In particular, their effectiveness is proven by means of the comparison with the analytical solutions available in the literature, both for isotropic and composite structures.
With respect to other approaches such as the Finite Element Method (FEM), the proposed methodologies are able to get the solution with few degrees of freedom. In addition, the convergence behavior is faster than the FEM.
A domain decomposition based on Isogeometric analysis is developed to analyze the mechanical behavior of arbitrarily shaped structures. The so-called blending functions are used to deal with discontinuities and distortions by means of a reduced number of elements [3, 4]. Thus, a nonlinear mapping is achieved by employing NURBS curves. According to the numerical method used in the computation, the strong and weak formulations are solved within each element. The effect of distorted meshes on the solution is investigated, as well. The numerical methods at issue are named Strong Formulation Finite Element Method (SFEM) and Weak Formulation Finite Element Method (WFEM).
References
[1] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., "Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey", Applied Mechanics Reviews, 67, 02081-1-55 (2015).
[2] Tornabene, F., Fantuzzi, Bacciocchi, M., "Strong and weak formulations based on differential and integral quadrature methods for the free vibration analysis of composite plates and shells: Convergence and accuracy", Engineering Analysis with Boundary Elements. In press. DOI: 10.1016/j.enganabound.2017.08.020.
[3] Fantuzzi, N., Tornabene, F., "Strong Formulation Isogeometric Analysis (SFIGA) for Laminated Composite Arbitrarily Shaped Plates", Composites Part B - Engineering, 96, 173-203 (2016).
[4] Tornabene, F., Fantuzzi, Bacciocchi, M., "The GDQ Method for the Free Vibration Analysis of Arbitrarily Shaped Laminated Composite Shells Using a NURBS-Based Isogeometric Approach", Composite Structures, 154, 190-218 (2016)
Modelling of Damaged Laminated and Sandwich Shell Structures by means of Higher-order Shear Deformation Theories
No full textThe main aim of the current research is the development of a mathematical formulation for the modelling of damage in laminated and sandwich composite shells. For this purpose, the damage of some areas of the structures can be seen as concentrated decays of the mechanical properties of the elastic constituents. In general, several kinds of damage can affect the mechanical behavior of a generic laminated structure, such as microcracking, debonding, fiber ruptures, and transverse matrix cracking, as specified in [1].
Without investigating the causes of the damage, the current approach suggests to introduce peculiar functions that multiply directly the mechanical properties of the elastic media, expressed in terms of engineering constants. To this aim, the Gaussian function and an ellipse shaped law are used to model a quick variation of the mechanical properties within the whole structural domain. By setting properly the parameters that characterize these distributions, it is possible to control the intensity of the deterioration and the width of the damaged areas, as well as the point of applications.
The present approach is employed to characterize the damage in some doubly-curved shells characterized by different radii of curvature. The difficulties related to the description of these curved surfaces are overcome by means of an analytical formulation based on differential geometry [2]. As far as the mechanical properties are concerned, several constituents are considered and combined.
The theoretical framework is based on a formulation that allows to develop easily different kinematic models and expansions in a unified manner. Thus, several Higher-order Shear Deformation Theories, which can include also the zig-zag effect, are employed. In fact, it has been proven that peculiar mechanical configurations require an enriched structural model, since lower-order theories could be inadequate to capture the effective mechanical behavior.
Finally, a numerical technique able to solve the strong form of the governing equations is used. For this purpose, the partial derivatives that appear in the fundamental system are directly approximated through the Generalized Differential Quadrature method due to its accuracy [3].
References
[1] Tornabene, F., Fantuzzi, N., Bacciocchi, M., “Linear Static Behavior of Damaged Laminated Composite Plates and Shells”, Materials, 10, 811, 1-52 (2017).
[2] Tornabene, F., Fantuzzi, N., Bacciocchi, M., and E. Viola, Laminated Composite Doubly-Curved Shell Structures. Differential Geometry. Higher-order Structural Theories, Esculapio, Bologna (2016).
[3] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., “Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey”, Applied Mechanics Reviews, 67, 020801-1-55
Strong and Weak Formulations for the Analysis of Arbitrarily Shaped Laminated Composite Structures
No full textA numerical approach is developed to deal with arbitrarily shaped structures. Two different methodologies are used to this aim, which are based on the Differential Quadrature and Integral Quadrature methods, respectively. These numerical methods are able to approximate both derivatives and integrals [1]. Therefore, the strong and weak formulations of the governing equations can be solved. As shown in the paper [2], these approaches are accurate, reliable and stable, when employed to obtain the mechanical response of various kinds of structures, such as plates, shells and membranes. In particular, their effectiveness is proven by means of the comparison with the analytical solutions available in the literature, both for isotropic and composite structures.
With respect to other approaches such as the Finite Element Method (FEM), the proposed methodologies are able to get the solution with few degrees of freedom. In addition, the convergence behavior is faster than the FEM.
A domain decomposition based on Isogeometric analysis is developed to analyze the mechanical behavior of arbitrarily shaped structures. The so-called blending functions are used to deal with discontinuities and distortions by means of a reduced number of elements [3, 4]. Thus, a nonlinear mapping is achieved by employing NURBS curves. According to the numerical method used in the computation, the strong and weak formulations are solved within each element. The effect of distorted meshes on the solution is investigated, as well. The numerical methods at issue are named Strong Formulation Finite Element Method (SFEM) and Weak Formulation Finite Element Method (WFEM).
References
[1] Tornabene, F., Fantuzzi, N., Ubertini, F., Viola, E., "Strong Formulation Finite Element Method Based on Differential Quadrature: A Survey", Applied Mechanics Reviews, 67, 02081-1-55 (2015).
[2] Tornabene, F., Fantuzzi, Bacciocchi, M., "Strong and weak formulations based on differential and integral quadrature methods for the free vibration analysis of composite plates and shells: Convergence and accuracy", Engineering Analysis with Boundary Elements. In press. DOI: 10.1016/j.enganabound.2017.08.020.
[3] Fantuzzi, N., Tornabene, F., "Strong Formulation Isogeometric Analysis (SFIGA) for Laminated Composite Arbitrarily Shaped Plates", Composites Part B - Engineering, 96, 173-203 (2016).
[4] Tornabene, F., Fantuzzi, Bacciocchi, M., "The GDQ Method for the Free Vibration Analysis of Arbitrarily Shaped Laminated Composite Shells Using a NURBS-Based Isogeometric Approach", Composite Structures, 154, 190-218 (2016)
Composite Structures
No full textThe past few decades have seen outstanding advances in the use of composite materials in structural applications. There can be little doubt that, within engineering circles, composites have revolutionised traditional design concepts and made possible an unparalleled range of new and exciting possibilities as viable materials for construction. Composite Structures, an International Journal, disseminates knowledge between users, manufacturers, designers and researchers involved in structures or structural components manufactured using composite materials.
The journal publishes papers which contribute to knowledge in the use of composite materials in engineering structures. Papers deal with design, research and development studies, experimental investigations, theoretical analysis and fabrication techniques relevant to the application of composites in load-bearing components for assemblies, ranging from individual components such as plates and shells to complete composite structures
Composites. Part C: Open Access
No full textThe journal publishes high-quality, peer-refereed original research articles and reviews on a broad range of composite materials. All research articles are freely available via the Internet upon publication to maximize the readership. Authors are welcome to submit your work to the most relevant topical section via its dedicated editorial channel: Sustainable Composites, Multi-functional Composites, Composite Structures
Mathematical Problems in Engineering
No full textMathematical Problems in Engineering is a peer-reviewed, Open Access journal that publishes results of rigorous engineering research carried out using mathematical tools. Contributions containing formulations or results related to applications are also encouraged. The primary aim of Mathematical Problems in Engineering is rapid publication and dissemination of important mathematical work which has relevance to engineering. All areas of engineering are within the scope of the journal. In particular, aerospace engineering, bioengineering, chemical engineering, computer engineering, electrical engineering, industrial engineering and manufacturing systems, and mechanical engineering are of interest. Mathematical work of interest includes, but is not limited to, ordinary and partial differential equations, stochastic processes, calculus of variations, and nonlinear analysis
Materials
No full textMaterials is an open access journal of related scientific research and technology development. It publishes reviews, regular research papers (articles) and short communications. Its aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. Therefore, there is no restriction on the length of the papers. The full experimental details must be provided so that the results can be reproduced.
Materials provides a forum for publishing papers which advance the in-depth understanding of the relationship between the structure, the properties or the functions of all kinds of materials. Chemical syntheses, chemical structures and mechanical, chemical, electronic, magnetic and optical properties and various applications will be considered
Structural and Computational Mechanics Book Series
No full textThe Esculapio Series in “Structural and Computational Mechanics” has been inaugurated with the aim of arranging a series of books in these key fields related to academic research, education and industrial applications. The Esculapio Series publishes high- level texts for academic students, deep studies on good practice and industrial technology, interesting and fundamental research topics related to industrial development and engineering practices. The readership encapsulates undergraduate and PhD students, researchers, scientists and free-lancers within applied mechanics topics. Civil/structural, mechanical, aerospace, naval, nuclear, automotive, materials, environmental, electrical, and biomedical engineers could benefit from this book series. The present book series would be the natural home for authors proficient in mechanics of materials, mechanics of structures as well as computational and applied mechanics. The Esculapio Series will focus on the following research areas, but not limited to: - Applied mechanics - Applied mathematics - Computational mechanics - Theoretical modeling - Engineering structures - Typical materials: concrete, metal, wood, masonry, etc. - Classical and advanced numerical methods - Composite Materials - Nonlinearities - Repair and reinforcements - Meta-materials and advanced materials - SMART structural component
Materials Proceedings
No full textMaterials Proceedings is an open access journal dedicated to publishing findings resulting from conferences, workshops, and similar events, in all areas of material sciences. The conference organizers and proceedings editors are responsible for managing the peer-review process and selecting papers for conference proceedings
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