1,721,169 research outputs found
Taylor, R L, 1200962
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/420551Surname: TAYLOR. Given Name(s) or Initials: R L. Military Service Number or Last Known Location: 1200962. Missing, Wounded and Prisoner of War Enquiry Card Index Number: SEA-2370.245261
Item: [2016.0049.52812] "Taylor, R L, 1200962
A shear-deformable plate element with an exact thin limit
No full textWe present a quadrilateral finite element developed within the framework of a shear deformable plate theory. The interpolation for the rotation takes advantage of internal rotational degrees of freedom (through the use of bubble functions), while the interpolation for the transverse displacement is linked to the nodal rotations. A careful study of the element behavior is performed using an extensive set of mixed patch tests; results from several numerical examples are also presented. The element has proper rank and excellent interpolating capacity. Moreover, without using any ad-hoc assumption (e.g., energy balancing schemes) the element presents no locking effects at all; in fact, the shear energy may be set identically equal to zero without introducing any ill-conditioning in the problem, thus recovering a proper thin plate limit
A force control methods for contact problems with large initial penetrations, Dept. of Civil Engineering, UCB Rep. N. UCB/SEMM-96/07, University of California at Berkeley, Berkeley, USA, 1996.
No full textRapporto interno, Dept. of Civil Engineering, UCB Rep. N. UCB/SEMM-96/07, University of California at Berkeley, Berkeley, USA
A triangular thick plate finite element with an exact thin limit
No full textWe present a new formulation for a triangular finite element developed within the framework of a shear deformable plate theory. The element takes advantage of internal rotational degrees of freedom and a linked interpolation between the transverse displacement and the rotations. The element has excellent interpolating capacity and presents no locking effects; in fact, the shear energy may be set identically equal to zero without introducing any ill-conditioning, thus recovering a proper thin plate limit
A generalized visco-plasticity model and its algorithmic implementation
No full textIn this work we present a new rate-dependent model, which has the feature of being bounded by two plasticity models. After a brief review of the continuous equations for a material with inelastic behavior governed by a von Mises (J2) yield function, including both linear isotropic and kinematic hardening mechanisms, we introduce their discrete counterpart within the framework of a return mapping algorithm. Hence, we address the new material model, called generalized visco-plasticity, which includes as sub-cases classical visco-plasticity, classical plasticity and generalized plasticity. We discuss both the continuous and the discrete-time version for the case of a J2 associative model. Moreover, we present its algorithmic implementation in a return map setting as well as the form of the discrete consistent tangent tensor, which guarantees quadratic convergence in a Newton iterative technique. Finally, some numerical simulations are presented to illustrate the performance of the new material model
A generalized elastoplastic plate theory and its algorithmic implementation
No full textIn continuum mechanics within specific classes of problems, one‐ or two‐dimensional theories are often simpler to apply than the more complete three‐dimensional one. This is, for example, the case of thin bodies, such as plates or shells, which may be studied using appropriate two‐dimensionai theories. Within this approach, the reduction of the dimension is traded for a loss of information relative to the motion in the transverse direction. For example, in the case of non‐linear material behaviour, classical plasticity plate theories are usually not able to model the effects related to the spreading of plasticity through the cross‐section. In the present paper we discuss a generalized plasticity plate model, which can be used to reproduce some of the three‐dimensional effects in a two‐dimensional setting. We present the continuous and the discrete time model, including both isotropic and kinematic hardening mechanisms; moreover, the form of the tangent matrix consistent with the discrete model is addressed. Finally, some examples (cantilever beam, clamped circular plate and clamped square plate under monotonic and cyclic loading) are studied numerically using a three‐dimensional classical plasticity theory, a classical plasticity plate theory and the proposed plate theory. The generalized plasticity plate model matches the three‐dimensional response with greater accuracy, than the classical plasticity plate model
A local discrete strain gap approach for the isogeometric analysis of thin shell structures
No full textIn this paper, we present an isogeometric method for the analysis of thin shell structures,
taking into consideration the linear elastic model [1] in a displacement-based formulation. The
aim of the present work is to develop a method for the elimination of geometrical locking
phenomena typical of vanishing thickness situations. Various methods, including the Discrete
Shear Gap method proposed by Bletzinger et al. [2] and generalized subsequently to the so called
Discrete Strain Gap method [3], are invoked for the approximation of the appropriate shear
strain components causing spurious deformation effects in pure bending situations. In order to
apply the methods the discrete equilibrium equations are derived element-wise resorting to the
extraction of Bernstein polynomials from the NURBS interpolation basis [4]. This step permits
to localize the displacement field over each single element and to apply the interpolation of
appropriate strain components through the discrete strain gaps at local nodes. An investigation
over a set of benchmark cases is presented
Shape-memory alloys: macromodelling and numerical simulations of the superelastic behavior
No full textA new model of generalized plasticity and its numerical implementation
No full textA previously proposed simple model of generalized plasticity is modified so that it allows behavior that is asymptotically perfectly plastic or strain-softening. Initially presented in uniaxial form, the model is then generalized to multiaxial stress. Numerical implementation is developed first through direct integration of the rate equations, including special cases in which the solution may be obtained analytically, and then by means of a return-map algorithm, which is particularly well suited to the finite-element method; consistent algorithmic tangent moduli are derived as well. Numerical examples are presented to illustrate the various approaches
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