000021526 001__ 21526
000021526 005__ 20170622131250.0
000021526 04107 $$aeng
000021526 046__ $$k2017-06-15
000021526 100__ $$aErrico, Fabrizio
000021526 24500 $$aAPPLICATION OF THE WAVE FINITE ELEMENT APPROACH TO THE STRUCTURAL FREQUENCY RESPONSE OF STIFFENED STRUCTURES

000021526 24630 $$n6.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000021526 260__ $$bNational Technical University of Athens, 2017
000021526 506__ $$arestricted
000021526 520__ $$2eng$$aThe present work shows many aspects concerning the use of the wave methodology for the response computation of periodic structures, through the use of substructures and single cells. Applying Floquet principle, continuity of displacements and equilibrium of forces at the interface, an eigenvalue problem, whose solutions are the waves propagation constants and wavemodes, is defined. With the use of single cells, thus a double periodicity, the dispersion curves of the waveguide under investigation are obtained and a validation of the results is performed with analytic ones, both for isotropic and composite material. Two different approaches are presented, instead, for computing the forced response of stiffened structures, through substructures of the whole periodic structure. The first one, dealing with the condensed-to-boundaries dynamic stiffness matrix, proved to drastically reduce the problem size in terms of degrees of freedom, with respect to more mature techniques such as the classic FEM. Moreover it proved to be the most controllable one. The other approach presented deals with waves propagation and reflection in the structure. However it suffers more numerical conditioning and requires a proper choice of the reflection matrices to the boundaries, which has been one of the most delicate passages of the whole work, as the effects of the direct excitation. However this last approach can deal with the response and loads applied on any inner point. The results show a good agreement with numerical classic-FEM except for damping needed to be trimmed for perfect agreement . The drastic reduction of DoF is evident, even more when the number of repetitive substructures is high and the substructures itself is modelled in order to get the lowest number of DoF at the boundaries. 

000021526 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000021526 653__ $$aWave Finite Element, Stiffened Structures Dynamics, Wave-mode expansion

000021526 7112_ $$aCOMPDYN 2017 - 6th International Thematic Conference$$cRhodes Island (GR)$$d2017-06-15 / 2017-06-17$$gCOMPDYN2017
000021526 720__ $$aErrico, Fabrizio$$iBareille, Olivier$$iRosa, Sergio De$$iIchchou, Mohamed
000021526 8560_ $$ffischerc@itam.cas.cz
000021526 8564_ $$s1383962$$uhttp://invenio.itam.cas.cz/record/21526/files/16878.pdf$$yOriginal version of the author's contribution as presented on CD, section: [MS05] Periodicity-induced effects and methods in structural dynamics
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000021526 962__ $$r21500
000021526 980__ $$aPAPER