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SANDWICH STRUCTURES 7: ADVANCINGWITH SANDWICH STRUCTURES AND MATERIALS Sandwich Structures 7: Advancing with Sandwich Structures and Materials Proceedings of the 7th International Conference on Sandwich Structures, Aalborg University, Aalborg, Denmark, 29-31 August 2005 Edited by O.T. THOMSEN Aalborg University, Aalborg, Denmark E. BOZHEVOLNAYA Aalborg University, Aalborg, Denmark and A. LYCKEGAARD Aalborg University, Aalborg, Denmark A C.I.P. Catalogue record for this book is available from the Library of Congress. ISBN-10 1-4020-3444-X (HB) ISBN-13 978-1-4020-3444-2 (HB) ISBN-10 1-4020-3848-8 (e-book) ISBN-13 978-1-4020-3848-8 (e-book) Published by Springer, P.O. Box 17, 3300 AA Dordrecht, The Netherlands. www.springeronline.com Printed on acid-free paper The cover depicts the ICSS-7 logo, by Kjeld Moseholm and Anders Lyckegaard. © Institute of Mechanical Engineering, Aalborg University, Denmark. Used by permission. All Rights Reserved © 2005 Springer No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Printed in the Netherlands. TABLE OF CONTENTS Preface xvii KEYNOTE LECTURES Sandwich structures: Past, present, andfuture 3 J.R. Vinson Sandwich structures technology in commercial aviation 13 A.S. Herrmann, P.C. Zahlen and I. Zuardy Damage assessment and damage tolerance of FRP sandwich structures 27 B. Hayman SESSIONSORGANISED BY THE ONR (Office of Naval Research, U.S. Navy, Program Manager Dr. Y. Rajapakse) Mechanics & Analysis Geometrical non-linear response of modern sandwich panels – Localized effects 47 Y. Frostig Global buckling of wide sandwich panels with orthotropic phases: An elasticity solution 57 G.A. Kardomateas Parametric study of structurallygraded core junctions 67 A. Lyckegaard, E. Bozhevolnaya and O.T. Thomsen Local effects induced by core junctions in sandwich beams under general loading conditions 77 E. Bozhevolnaya, A. Lyckegaard and O.T. Thomsen v vi Table of Contents Material characterization of PVC foam under staticanddynamic loading 87 D.C. Loup, R.C. Matteson and A.W.J. Gielen Dynamics Dynamic response of anisotropic sandwich panelstounderwater and in-airexplosions 97 L.Librescu, S.-Y. Oh and J. Hohe Enhancement of blast resistance of sandwich plates 107 G.J. Dvorak and Y.A. Bahei-El-Din Failure, Fracture, Damage and Fatigue A two-propertyyield, failure (fracture) criterion for isotropic matrix materials 117 R.M. Christensen On crack extension in foam cored sandwich fracture specimens 121 R.C. Matteson, L.A. Carlsson, F. Aviles and D.C. Loup Effect of geometric constraint on fracture toughness of PVC foam core sandwichbeams 131 K. Shivakumar, H. Chen and A. Bhargava Damage evaluation of sandwich structures using vibration and thermal signatures 143 A. Cecchini, F. Just-Agosto, D. Serrano and B. Shafiq Fatigue performance and size effects in sandwich composites 153 B. Shafiq, A. Quispitupa, F. Just and M. Banos Study of fatigue endurance of conventional and modified core junctions in sandwich beams 161 E. Bozhevolnaya, A. Lyckegaard and O.T. Thomsen Fatigue of closed cell foams 171 D.Zenkert, A. Shipshaand M. Burman Table of Contents vii Fatigue of pure and nanophased sandwich composites under shear loading 183 H.Mahfuz, S. Zainuddin, M.F. Uddin, V.K. Rangari and S. Jeelani Environmental Degradation Sea water effects on polymeric foams and their sandwichlay-ups 193 Y.J. Weitsman, X. Li and A. Ionita MODELLING, ANALYSIS AND DESIGN Sandwich plates: Stresses, deflection, buckling and wrinkling loads 201 H.-R. Meyer-Piening Modelling of viscoelastically damped sandwich beams: A comparative study 211 H. Hu, S. Belouettar, E. Daya and M. Potier-Ferry A homogenization based theory for laminated and sandwich beams 221 J.S. Hansen, G. Kennedy and S.F.M. de Almeida Modelling of composite and sandwich plates by a trigonometric layerwise theory and multiquadrics 231 C.M.C. Roque, A.J.M. Ferreira and R.M.N. Jorge Stabilitybehaviour of cylindrical and conical sandwich shellswith flexible core 241 C. Zhong and H.-G. Reimerdes High order nonlinear contact effects in the dynamic behavior of delaminated sandwich panels with a flexible core 251 H. Schwarts-Givli, O. Rabinovitch and Y. Frostig Bending behavior of sandwich panels with a “soft” core and embedded rigid inserts 261 O. Rabinovitch and E. Hamed Elastic behaviour of Zreinforced sandwichbeams 271 M. Leite, A. Silva and M. Freitas viii Table of Contents Wrinkling of shallow sandwich shells for the general case of multi-axial orthotropy, curvature andloading 281 V. Skvortsov andO.T. Thomsen Transverse stresses of a filler under multipoint loading of a sandwich panel 291 V.A. Polyakov, R.P. Shlitsa, V.V. Khitrov and V. I. Z higun A triangular finite element for sandwich plates accounting for transverse core compressibility 301 S. Demiray, W. Becker and J. Hohe Finite element for the static and stability analysis of sandwich plates 311 M.Linke, W. Wohlers and H.-G. Reimerdes Two FE formulations for a rapid 3D stress analysis of composite sandwich structures 321 A. Wetzel and L. Kärger Sandwich materials selection charts 331 J. Pflug and I. Verpoest Optimal design of laminated extended & honeycomb cores sandwich panelsunder out-of-plane load with simply supportedboundary conditions usinggeneticalgorithm 341 M.J. Jamali, I. Rajabiand M.H. Kadivar Designing sandwichinserts and core junctions for maximum structural stiffness usingdiscrete material optimization 351 J. Stegmann and E. Lund FRACTURE AND DAMAGE TOLERANCE On residual compressive strength prediction of composite sandwich panels after low-velocity impact damage363 Z. Xie, A.J. Vizzini and M. Yang Investigation of parameters dictating damage and energy adsorption characteristics in sandwich panels 373 G.Zhou, M. Hill and N. Hookham Table of Contents ix Real-time damage detection ofhoneycomb sandwich structures using small-diameter fiber Bragg grating sensors 383 S.Minakuchi, Y. Okabeand N. Takeda The influence offace sheet wrinkle defects on the performance of FRP sandwich structures 393 B.Hayman, C. Berggreen and R. Pettersson Residual strength ofdebonded sandwich panels loaded withlateral pressure 403 P. Jolma, S. Segercrantz and C. Berggreen Measurement of interface fracture toughness of sandwich structures 413 R.C. Østergaard and B.F. Sørensen Numerical study of fractured sandwich composites under flexural loading 423 E.E. Theotokoglou, L.A. Carlsson, C.D. Vrettos and H. Mahfuz Dependence of sandwich damage initiation and crack propagation on core material fracture properties 433 L. Berger, M. Morgenthaler, W. Cantwell, K. Feichtinger and R. Elkin Dependence ofinplane sandwich shear deformation on core material type and thickness 441 M. Morgenthaler, L. Berger, K. Feichtinger and R. Elkin Residual strength of in-plane loaded debonded sandwich panels. Experimental investigation 451 C. Lundsgaard-Larsen, C. Berggreen and A. Nøkkentved Residual strength of in-plane loaded debonded sandwich panels. Fracture mechanical modelling 461 C. Berggreen and B.C. Simonsen Resistance of fastenings of sandwich panels 471 P. H assinen x Table of Contents Experimentalfailure mode determination of GRP/PVC-foam sandwich T-joints 477 A.W.J. Gielen, W. Trouwborst and D.C. Loup Flexuralbehaviour of aluminium foam/composite structures 487 M.Styles, P. Compston and S. Kalyanasundaram Repairclassification for sandwich panelswithhail damage 497 M.Das,E.Madenci and H. Razi Damage tolerance assessment of repaired composite sandwich structures 507 R. Trask, B. Cripps and A. Shenoi DYNAMICS, VIBRATION AND SOUND Dynamical transient response of shallow sandwich panel subjected to pressure field 519 S. Kadyrov and V. Skvortsov Effect of transverse core compressibility on dynamic buckling of sandwich structures 527 J. Hohe, L. Librescu and S.Y. Oh Dynamiccharacterisation of marine sandwich structures 537 M.Battley, I. Stenius, J. Breder and S. Edinger Local free vibration analysis of initially stressed curved sandwich beam 547 W. Wang and R.A. Shenoi Vibration analysis of composite sandwich plates and layup optimization 557 H. Sekine, H. Shirahata and M. Matsuda Flexural vibrations of a three-layer sandwich beam 567 D. Backström and A. Nilsson Aneffective 2D linear elasticity vibrational modelfor layered and sandwich clamped-clamped unidirectional strips 577 S. Karczmarzyk Table of Contents xi Minimization of acoustic radiation from composite sandwich structures 587 H.Denliand J.Q. Sun On wave propagation in sandwich plates under heavy fluid loading 597 S. Sorokin and N. Peake Wave propagation in a sandwich plate loadedbyaviscous compressible fluid 605 A.V. Chubinskiy and S.V. Sorokin IMPACT Impact damageonlightweight sandwich panels 615 D. Zhou and W.J. Stronge Ballistic resistance of 2D & 3D woven sandwich composites 625 A. Shukla, J. Grogan, S.A. Tekalur, A. Bogdanovich and R.A. Coffelt Impact and indentation behavior of sandwich panels 635 C.-J. Lindholm A comparison of low energy impact behaviour in aluminium foam and polymer foam sandwich structures 643 P. Compston, M. Styles and S. Kalyanasundaram Numerical modeling of sandwich panel response to ballistic loading 653 J. Kepler and M.R. Hansen Low velocity impact investigations of sandwich panels with different cores 661 W. Göttner and H.-G. Reimerdes Mechanical behavior of rubber-filled multifunctional honeycomb sandwich composite 671 H.Hao, C.-R. Joe and D.-U. Kim Stitching effect on static and dynamic behaviour of sandwich structures 681 B. Lascoup, Z. Aboura, K. Khellil and M. Benzeggagh xii Table of Contents PROCESSING AND FABRICATION Continuous manufacturing and performance of 3D reinforced sandwich structures 693 G.LeRoy, C. Binetruy and P. Krawczak A novel extrusion-welded sandwich structure for thermoplastic composite storagetanks 703 E. Lagardere, M.-F. Lacrampe, O. Skawinski, P. Krawczak,C.Ducret and M. Giletti The opportunities offlexible foam processing for rigid foam sandwich cores 713 H. Mispreuve and L.
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