Author
Jack R. Vinson
Bio: Jack R. Vinson is an academic researcher from University of Delaware. The author has contributed to research in topics: Shell (structure) & Sandwich-structured composite. The author has an hindex of 30, co-authored 168 publications receiving 8303 citations.
Papers published on a yearly basis
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01 Jan 1989
TL;DR: In this paper, the governing equations for a thin plate subjected to both in-plane and lateral loads have been derived, and one governing equation describing the relationship between the lateral deflection and the laterally distributed loading has been derived.
Abstract: The governing equations for a thin plate subjected to both in-plane and lateral loads have been derived previously. In those equations, there was one governing equation describing the relationship between the lateral deflection and the laterally distributed loading,
$$ D{
abla ^4}w = p\left( {x,y} \right) $$
and other equations dealing with in-plane displacements, related to in-plane loads
$$ {{
abla }^{4}}{{u}_{0}} = {{
abla }^{4}}{{v}_{0}} = 0. $$
.
01 Jan 2005
01 Jan 1993
TL;DR: In this paper, De Silva et al. considered the problem of axisymmetric loading of thin elastic paraboloidal shells of revolution which includes the effect of transverse shear deformation by using equations developed by Naghdi.
Abstract: De Silva [17.28] has considered the problem of axisymmetric loading of thin elastic paraboloidal shells of revolution which includes the effect of transverse shear deformation by using equations developed by Naghdi [19.1]. The transverse shear deformation is accounted for due to thickness considerations, and the material system considered is isotropic. That differs from the present theory which accounts for transverse shear deformation because of the large Eo/Goξ and Eθ/Gθξ ratios involved with many composite materials although the shell is geometrically thin. Therefore, the two theories are not identical.
01 Jan 1993
TL;DR: In this article, axially symmetric vibrations are discussed first so that through their simplicity, it is easy to see how static equations are easily transformed to dynamic equations, and to show the relation to the vibrations of beams: with and without an elastic foundation.
Abstract: Entire texts are needed to discuss shell vibrations in their entirety. In this Chapter, axially symmetric vibrations are discussed first so that through their simplicity, it is easy to see how static equations are easily transformed to dynamic equations, and to show the relation to the vibrations of beams: with and without an elastic foundation. Next, the general vibration characteristic of shells are shown through the study of cylindrical shells, also relating the behavior to beam vibrations. Through the work of Koga, only five types of boundary conditions are needed to study any and all boundary conditions. Next, the time portion of dynamic loads is presented in an easy to use manner to study impact response of shells. Finally, the important areas of shells vibrating in beam modes is studied, using two different approaches. This chapter and the references given provide a background for further study of shell vibrations. In Chapter 21, the vibrations of composite shells is discussed and could be studied upon completing this Chapter.
01 Feb 1998
TL;DR: In this paper, a cantilever beam with piezoelectric upper and lower surface strips is chosen as a vehicle for such sensitivity analyses, and it is shown that either stabilizing or destabilizing effects can be achieved depending on the phase relations of the three viscoelastic responses.
Abstract: In a previous paper, the authors formulated and evaluated the general nonlinear 3-D large deformation theory of anisotropic nonhomogeneous piezo-electrothermo-viscoelasticity including thermal expansion, curing and aging effects. For linear materials and small deformations, a piezoelastic/piezo-viscoelastic analogy was established in terms of integral Fourier and Laplace transforms. These developments are used in the present paper to evaluate the dynamic interactions between viscoelastic material damping and piezoelectric effects on voltage generation and structural control. A cantilever beam with piezoelectric upper and lower surface strips is chosen as a vehicle for such sensitivity analyses. The model has three distinct viscoelastic properties, namely the beam itself, the strip rigidity and a viscoelastic-emf constitutive relation. It is shown that either stabilizing or destabilizing effects can be achieved depending on the phase relations of the three viscoelastic responses.
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TL;DR: This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them, and summarizes cellulOSE nanoparticles in terms of particle morphology, crystal structure, and properties.
Abstract: This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).
4,920 citations
TL;DR: In this paper, a scaling analysis is performed to demonstrate that the effectiveness of actuators is independent of the size of the structure and evaluate various piezoelectric materials based on their effectiveness in transmitting strain to the substructure.
Abstract: This work presents the analytic and experimental development of piezoelectric actuators as elements of intelligent structures, i.e., structures with highly distributed actuators, sensors, and processing networks. Static and dynamic analytic models are derived for segmented piezoelectric actuators that are either bonded to an elastic substructure or embedded in a laminated composite. These models lead to the ability to predict, a priori, the response of the structural member to a command voltage applied to the piezoelectric and give guidance as to the optimal location for actuator placement. A scaling analysis is performed to demonstrate that the effectiveness of piezoelectric actuators is independent of the size of the structure and to evaluate various piezoelectric materials based on their effectiveness in transmitting strain to the substructure. Three test specimens of cantilevered beams were constructed: an aluminum beam with surface-bonded actuators, a glass/epoxy beam with embedded actuators, and a graphite/epoxy beam with embedded actuators. The actuators were used to excite steady-state resonant vibrations in the cantilevered beams. The response of the specimens compared well with those predicted by the analytic models. Static tensile tests performed on glass/epoxy laminates indicated that the embedded actuator reduced the ultimate strength of the laminate by 20%, while not significantly affecting the global elastic modulus of the specimen.
2,719 citations
Grenoble Institute of Technology1, National University of Mar del Plata2, Case Western Reserve University3, University of Fribourg4, University of Nottingham5, Virginia Tech6, University of Natural Resources and Life Sciences, Vienna7, University of Leoben8, Kyoto University9, Oregon State University10, Portland State University11, Imperial College London12, Queen Mary University of London13
TL;DR: An overview of recent progress in the area of cellulose nanofibre-based nanocomposites is given in this article, with particular emphasis on applications, such as reinforced adhesives, to make optically transparent paper for electronic displays, to create DNA-hybrid materials, to generate hierarchical composites and for use in foams, aerogels and starch nanocom composites.
Abstract: This paper provides an overview of recent progress made in the area of cellulose nanofibre-based nanocomposites. An introduction into the methods used to isolate cellulose nanofibres (nanowhiskers, nanofibrils) is given, with details of their structure. Following this, the article is split into sections dealing with processing and characterisation of cellulose nanocomposites and new developments in the area, with particular emphasis on applications. The types of cellulose nanofibres covered are those extracted from plants by acid hydrolysis (nanowhiskers), mechanical treatment and those that occur naturally (tunicate nanowhiskers) or under culturing conditions (bacterial cellulose nanofibrils). Research highlighted in the article are the use of cellulose nanowhiskers for shape memory nanocomposites, analysis of the interfacial properties of cellulose nanowhisker and nanofibril-based composites using Raman spectroscopy, switchable interfaces that mimic sea cucumbers, polymerisation from the surface of cellulose nanowhiskers by atom transfer radical polymerisation and ring opening polymerisation, and methods to analyse the dispersion of nanowhiskers. The applications and new advances covered in this review are the use of cellulose nanofibres to reinforce adhesives, to make optically transparent paper for electronic displays, to create DNA-hybrid materials, to generate hierarchical composites and for use in foams, aerogels and starch nanocomposites and the use of all-cellulose nanocomposites for enhanced coupling between matrix and fibre. A comprehensive coverage of the literature is given and some suggestions on where the field is likely to advance in the future are discussed.
2,214 citations
TL;DR: The most important members of the hexaferrite family are shown below, where Me = a small 2+ ion such as cobalt, nickel, or zinc, and Ba can be substituted by Sr: • M-type ferrites, such as BaFe12O19 (BaM or barium ferrite), SrFe 12O19(SrM or strontium ferite), and cobalt-titanium substituted M ferrite, Sr- or BaFe 12−2xCoxTixO19, or CoTiM as discussed by the authors.
1,855 citations
TL;DR: The numerical implementation of the model of brittle fracture developed in Francfort and Marigo (1998) is presented in this paper, where various computational methods based on variational approximations of the original functional are proposed.
Abstract: The numerical implementation of the model of brittle fracture developed in Francfort and Marigo (1998. J. Mech. Phys. Solids 46 (8), 1319–1342) is presented. Various computational methods based on variational approximations of the original functional are proposed. They are tested on several antiplanar and planar examples that are beyond the reach of the classical computational tools of fracture mechanics.
1,617 citations