DOCSLIB.ORG

Computational Methods for Structural Mechanics and Dynamics

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Computational Methods for Structural Mechanics and Dynamics NASA Conference Publication 3034 Part 2 Computational Methods for Structural Mechanics and Dynamics Edited by W. Jefferson Stroud Jerrold M. Housner John A. Tanner and Robert J. Hayduk NASA Langley Research Center Hampton, Virginia Proceedings of a workshop sponsored by the National Aeronautics and Space Administration and held at NASA Langley Research Center Hampton, Virginia June 19-21, 1985 National Aeronautics and Space Administration Office of Management Scientific and Technical Information Division 1989 PREFACE This document contains the proceedings of the Workshop on Computational Methods for Structural Mechanics and Dynamics held at NASA Langley Research Center, June 19-21, 1985. The workshop was sponsored by NASA Langley Research Center. The workshop had two objectives. The first objective was to introduce to the structural analysis technical community a new Langley research activity in structural analysis called Computational Structural Mechanics, or CSM. The second objective was to hear experts discuss important structural analysis problems and methods for solving those problems. The workshop was organized into the following four sessions: 1. Local/Global Nonlinear Stress Analysis - Full day - June 19 2. Tire Modeling Half day - June 20 3. Transient Dynamics Half day - June 20 4. Multi-Body Dynamics Full day - June 21 Each sess on closed with a panel discussion. Papers in these proceedings are grouped by session and identified in the contents. The order of the papers is the order of the presentations at the workshop. The proceedin s also include any transcription of questions and answers that followed each paper and panel discussions that followed each session. The use of trade names or names of manufacturers in this publication does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the National Aeronautics and Space Administration. W. Jefferson Stroud Jerrold M. Housner John A. Tanner Robert J. Hayduk Workshop Co-Chairmen PRECEDING PAGE BLANK NOT FILMED iii CONTENTS PREFACE ......................................................................... iii CONTENTS ....................................................................... v INTRODUCTION: Computational Structural Mechanics Activity ...................... 1 PART 1* UXXL/GLOBAL NONLINEAR STRESS ANALYSIS SOME ISSUES IN NUMERICAL SIMULATION OF NONLINEAR STRUCTURAL RESPONSE ............ 7 H. D. Hibbitt COMPUTERIZED STRUCTURAL MECHANICS FOR 1990’s: ADVANCED AIRCRAFT NEEDS .......... 25 A. V. Viswanathan and B. F. Backman NONLINEAR RESPONSE OF A BLADE-STIFFENED GRAPHITE-EPOXY PANEL WITH A DISCONTINUOUS STIFFENER: WORK IN PROGRESS .................................... 51 Norman F. Knight, Jr., William H. Greene, and W. Jefferson Stroud COMPUTATIONAL PROCEDURES FOR POSTBUCKLING OF COMPOSITE SHELLS ................... 67 G. M. Stanley and C. A. Felippa A REVIEW OF SOME PROBLEMS IN GLOBAL-LOCAL STRESS ANALYSIS ....................... 89 Richard B. Nelson SOME COMMENTS ON GLOBAL-LOCAL ANALYSES .......................................... 103 Satya N. Atluri ON COMPUTATIONAL SCHEMES FOR GLOBAL-LOCAL STRESS ANALYSIS ....................... 123 J. N. Reddy GLOBAL FUNCTIONS IN GLOBAL-LOCAL FINITE-ELEMENT ANALYSIS OF LOCALIZED STRESSES IN PRISMATIC STRUCTURES .............................................. 135 Stanley B. Dong GLOBAL-LOCAL METHODOLOGIES AND THEIR APPLICATION TO NONLINEAR ANALYSIS .......... 151 Ahmed K. Noor APPLICATION OF THE P-VERSION OF THE FINITE-ELEMENT METHOD TO GLOBAL-LOCAL PROBLEMS .......................................................... 169 Barna A. Szabd QUESTION AND ANSWER SESSION ..................................................... 179 PANEL DISCUSSION ................................................................ 190 *Presented under separate cover V PRECEDING PAGE BLANK NOT FILMED TIRE MODELING FEATURES AND CHARACTERIZATION NEEDS OF RUBBER COMPOSITE STRUCTURES .............. 211 Farhad Tabaddor NONLINEAR HIERARCHICAL SUBSTRUCTURAL PARALLELISM AND COMPUTER ARCHITECTURE ...... 249 Joe Padovan ADAPTIVE METHODS, ROLLING CONTACT, AND NONCLASSICAL FRICTION LAWS ............... 269 J. T. Oden CONTACT SOLUTION ALGORITHMS ..................................................... 291 John T. Tielking EXPLOITING SYMMETRIES IN THE MODELING AND ANALYSIS OF TIRES ..................... 317 Ahmed K. Noor, C. M. Andersen and John A. Tanner PANEL DISCUSSION ................................................................ 331 PART 2 TRANSIENT DYNAMICS SUMMARY: TRANSIENT DYNAMICS .................................................... 341 Robert J. Hayduk IMPROVING TRANSIENT ANALYSIS TECHNOLOGY FOR AIRCRAFT STRUCTURES ................. 343 R. J. Melosh and Mladen Chargin EXPLICIT, IMPLICIT, AND HYBRID METHODS .......................................... 355 T. Belytschko UNCONDITIONALLY STABLE CONCURRENT PROCEDURES FOR TRANSIENT FINITE-ELEMENT ANALYSIS ....................................................... 369 Michael Ortiz and Bahram Nour-Omid TRANSIENT ANALYSIS TECHNIQUES IN PERFORMING IMPACT AND CRASH DYNAMIC STUDIES .... 383 A. B. Pifko and R. Winter APPLICATION AND IMPLEMENTATION OF TRANSIENT ALGORITHMS IN COMPUTER PROGRAMS ..... 407 David J. Benson QUESTION AND ANSWER SESSION ..................................................... 419 PANEL DISCUSSION ................................................................ 425 vi MULTI-BODY DYNAMICS RECENT DEVELOPMENTS IN DEPLOYMENT ANALYSIS SIMULATION USING A MULTI-BODY COMPUTER CODE ................................................................. 435 Jerrold M. Housner DYNAMIC ANALYSIS OF SPACE STRUCTURES INCLUDING ELASTIC, MULTIBODY, AND CONTROL BEHAVIOR .............................................................. 443 Larry Pinson and Keto Soosaar Part 1: DYNAMICS OF FLEXIBLE MULTI-BODY MECHANISMS AND MANIPULATORS: AN OVERVIEW ................................................................... 455 Steven Dubowsky Part 2: APPLICATION OF FINITE-ELEMENT METHODS TO DYNAMIC ANALYSIS OF FLEXIBLE SPATIAL AND CO-PLANAR LINKAGE SYSTEMS ................................ 459 Steven Dubowsky DYNAMICS OF ARTICULATED STRUCTURES .............................................. 491 Edward J. Haug MODAL REDUCTION STRATEGIES FOR INTERCONNECTED FLEXIBLE BODIES SIMULATION ........ 517 F. 0. Eke and G. K. Man COMPUTATIONAL ASPECTS OF MULTI-BODY DYNAMICS .................................... 527 K. C. Park CONSTRAINT ELIMINATION IN DYNAMICAL SYSTEMS ..................................... 537 R. P. Singh and P. W. Likins NONLINEAR CHARACTERISTICS OF JOINTS AS ELEMENTS OF MULTI-BODY DYNAMIC SYSTEMS ....................................................................... 543 Edward F. Crawley QUESTION AND ANSWER SESSION ..................................................... 571 PANEL DISCUSSION ................................................................ 589 vii PART 2 TRANSIENT DYNAMICS 339 SulmARY THURSDAY, JUNE 20 - TRANSIENT DYNAMICS Robert J . Hayduk, NASA Langley Research Center: We have an interesting session for you this afternoon on transient dynamics. One paper will project oppor- tunities for increasing the efficiency and accuracy of computer codes. Two papers will discuss implementation and experience in time-stepping a1 gorithms, and two papers will give some results on applications of various codes on the scaler and vector machines that are available today. Everyone has his pet problem in nonlinear structural dynamics. I'm no excep- tion. In order to begin this session, let me show you a problem that is of interest to the CSM group here at Langley and to me. This is a four-sequence photograph of the December 1, 1984 Control led Impact Demonstration (CID) crash test of a Boeing 720 aircraft. We had planned for the impact to be symmetric, but that isn't what happened. The aircraft touched down with the left wing rolled at approximately 11 degrees with the aircraft nearly level but yawed about 11 to 12 degrees. This caused the aircraft to pitch nose down, and the fuselage to impact on the nose first. We had planned for the aircraft to be slightly pitched up to achieve an initial impact on the aft end of the fuselage. After about 1.8 seconds, the aircraft slid into some wing cutters, which opened UP the number three engine--the inboard engine of the right side of the aircraft. The disintegrating engine caused a huge fire to erupt as you can see frm this last photograph. At the time of contact with the wing openers, the aircraft was yawed approximately 38 degrees. Now what we'd like to be able to do--in fact, what we had planned initially to do--was to analyze this impact for the initial portion of the crash scenario--the portion prior to impact with the wing cutter. With the asymetric impact that actually occurred in the test, we have to use a full finite element model that can handle the asymmetric case. Eventually we would like to analyze the longer duration impact with the wing cutters and the slide out beyond, which is about another 2.5 seconds. The initial attempt at analysis i.rith the symmetric half model, which is a very simp1 e beam stringer and membrane model with nonlinear springs of about 220-some elements, and 230 equations, simulating approximately 0.4 second with a full Cyber 175, cost us about 1.4 hours of computer time with the DYCAST computer program. If this problem is scaled up to a machine that would give us perhaps a 10-to-1 increase in computer speed with a full model approximately 1100 masses, 341 PRECEDING PAGE BLANK NOT FlLlvlED 4000 elements, and
Load more

Recommended publications
  • Symmetry Groups and Conservation Laws in Structural Mechanics
    Proceedings of Institute of Mathematics of NAS of Ukraine 2000, Vol. 30, Part 1, 223–230. Symmetry Groups and Conservation Laws in Structural Mechanics Vassil M. VASSILEV and Peter A. DJONDJOROV Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bontchev St., Bl.4, 1113 Sofia, Bulgaria E-mails: [email protected] and [email protected] Recent results concerning the application of Lie transformation group methods to structural mechanics are presented. Focus is placed on the point Lie symmetries and conservation laws inherent to the Bernoulli–Euler and Timoshenko beam theories as well as to the Marguerre- von K´arm´an equations describing the large deflection of thin elastic shallow shells within the framework of the nonlinear Donnell–Mushtari–Vlasov theory. 1 Introduction The present paper is concerned with the invariance properties (point Lie symmetries) of three classes of self-adjoint partial differential equations arising in structural mechanics – the dynamic beam equations of Bernouli–Euler and Timoshenko type governing vibration of beams on a variable elastic foundation and dynamic stability of fluid conveying pipes, and Marguerre-von K´arm´an equations describing the large deflection of thin isotropic elastic shallow shells subjected to an external transverse load and a nonuniform heating. Once the invariance properties of a given differential equation are established, several impor- tant applications are available. First, it is possible to obtain classes of group-invariant solutions. For a self-adjoint equation another application of its symmetries arises since it is the Euler– Lagrange equation of a certain functional. If a symmetry group of such an equation turned out to be its variational symmetry as well, that is a symmetry of the associated functional, then Noether’s theorem guarantees the existence of a conservation law for the solutions of this equation.
    [Show full text]
  • Structural Analysis
    Structural Analysis Structural Analysis Photo courtesy of Institute of Dynamics and Vibration Research, Leibniz Universität Hannover, Germany Leibniz Universität Hannover, Research, Photo courtesy of Institute Dynamics and Vibration m+p Analyzer’s structural analysis package provides • Multiple Degree of Freedom (MDOF) analysis a complete set of tools for observing, analyzing and • Circle fit wizard to review and validate FRF data and documenting the vibrational behaviour of machines and mode shapes mechanical structures. Different software modules cover a • Operational modal analysis (OMA) wide range of techniques including impact testing, shaker • Modal model validation (MAC, MPD, MPC, MOV, MIF) measurements (SIMO and MIMO), experimental and • Polyreference Time Domain algorithm (PTD/PolyTime) operational modal analysis, ground vibration testing, • Polyreference Time Domain Plus algorithm (PTD+/ operating deflection shape analysis, and modal model Polytime+) validation. • Polyreference Least-Squares Complex Frequency domain algorithm (p-LSCF/Polyfreq) The standard structural dynamics package includes: • Multiple Input/Multiple Output (MIMO) analysis including • Impact testing using a modal hammer multi-source outputs • Creation of component-based geometries • Swept and stepped sine analysis • Operating Deflection Shape (ODS) analysis • Ground vibration testing (GVT) with Normal Mode Optional software modules are available to cover the most Tuning (NMT) demanding and advanced modal analysis applications: • Interface to FEMtools for Structural
    [Show full text]
  • Nonlinear Dynamics in Mechanics and Engineering: 40 Years of Developments and Ali H
    This is a post-peer-review, pre-copyedit version of the paper Nonlinear dynamics in mechanics and engineering: 40 years of developments and Ali H. Nayfeh’s legacy by Giuseppe Rega Department of Structural and Geotechnical Engineering, Sapienza University of Rome, Italy Please cite this work as follows: Rega, G., Nonlinear dynamics in mechanics and engineering: 40 years of developments and Ali H. Nayfeh’s legacy, Nonlinear Dynamics, 99(1), 11-34, 2020, DOI: 10.1007/s11071-019-04833-w. Publisher link and Copyright information: You can download the final authenticated version of the paper from: http://dx.doi.org/10.1007/s11071-019-04833-w. © 2020 Springer Nature Switzerland AG This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by- nc-nd/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA. Licensees may copy, distribute, display and perform the work and make derivative works and remixes based on it only if they give the author or licensor the credits (attribution) in the manner specified by these. Licensees may copy, distribute, display, and perform the work and make derivative works and remixes based on it only for non-commercial purposes. Licensees may copy, distribute, display and perform only verbatim copies of the work, not derivative works and remixes based on it. Nonlinear Dynamics in Mechanics and Engineering: Forty Years of Developments and Ali H. Nayfeh’s Legacy Giuseppe Rega Department of Structural and Geotechnical Engineering, Sapienza University of Rome, Italy e-mail: [email protected] Abstract: Nonlinear dynamics of engineering systems has reached the stage of full maturity in which it makes sense to critically revisit its past and present in order to establish an historical perspective of reference and to identify novel objectives to be pursued.
    [Show full text]
  • Designed Beam Deflections Lab Project
    Paper ID #30349 Designed Beam Deflections Lab Project Dr. Wei Vian, Purdue University at West Lafayette Wei Vian is a continuing lecturer in the program of Mechanical Engineering Technology at Purdue Uni- versity Statewide Kokomo campus. She got her Ph.D from Purdue Polytechnic, Purdue University, West Lafayette. She got her bachelor and master degree both from Eastern Michigan University. Her recent research interests include grain refinement of aluminum alloys, metal casting design, and innovation in engineering technology education. Prof. Nancy L. Denton PE, CVA3, Purdue Polytechnic Institute Nancy L. Denton is a professor in Purdue University’s School of Engineering Technology, where she serves as associate head. She served on the Vibration Institute’s Board of Directors for nine years, and is an active member of the VI Academic and Certification Scheme Committees. She is a Fellow of ASEE and a member of ASME. c American Society for Engineering Education, 2020 Designed Beam Deflections Lab Project Abstract Structural mechanics courses generally are challenging for engineering technology students. The comprehensive learning process requires retaining knowledge from prior mechanics, materials, and mathematic courses and connecting theoretical concepts to practical applications. The various methods for determining deflection of the beams, especially statically indeterminate beams, are always hard for students to understand and require substantial effort in and out of class. To improve learning efficacy, enhance content understanding, and increase structural learning interest, a laboratory group project focusing on beam deflections has been designed for strength of materials students. The project spans design, analysis, construction, and validation testing of a metal bridge. Students design, construct, and test their bridges and do corresponding beam deflection calculations to verify the beam deflection type.
    [Show full text]
  • Structural Mechanics MODULE V ERIFICATION M ANUAL
    COMSOL Multiphysics Structural Mechanics MODULE V ERIFICATION M ANUAL V ERSION 3.5 How to contact COMSOL: Germany United Kingdom COMSOL Multiphysics GmbH COMSOL Ltd. Benelux Berliner Str. 4 UH Innovation Centre COMSOL BV D-37073 Göttingen College Lane Röntgenlaan 19 Phone: +49-551-99721-0 Hatfield 2719 DX Zoetermeer Fax: +49-551-99721-29 Hertfordshire AL10 9AB The Netherlands [email protected] Phone:+44-(0)-1707 636020 Phone: +31 (0) 79 363 4230 www.comsol.de Fax: +44-(0)-1707 284746 Fax: +31 (0) 79 361 4212 [email protected] [email protected] Italy www.uk.comsol.com www.comsol.nl COMSOL S.r.l. Via Vittorio Emanuele II, 22 United States Denmark 25122 Brescia COMSOL, Inc. COMSOL A/S Phone: +39-030-3793800 1 New England Executive Park Diplomvej 376 Fax: +39-030-3793899 Suite 350 2800 Kgs. Lyngby [email protected] Burlington, MA 01803 Phone: +45 88 70 82 00 www.it.comsol.com Phone: +1-781-273-3322 Fax: +45 88 70 80 90 Fax: +1-781-273-6603 [email protected] Norway www.comsol.dk COMSOL AS COMSOL, Inc. Søndre gate 7 10850 Wilshire Boulevard Finland NO-7485 Trondheim Suite 800 COMSOL OY Phone: +47 73 84 24 00 Los Angeles, CA 90024 Arabianranta 6 Fax: +47 73 84 24 01 Phone: +1-310-441-4800 FIN-00560 Helsinki [email protected] Fax: +1-310-441-0868 Phone: +358 9 2510 400 www.comsol.no Fax: +358 9 2510 4010 COMSOL, Inc. [email protected] Sweden 744 Cowper Street www.comsol.fi COMSOL AB Palo Alto, CA 94301 Tegnérgatan 23 Phone: +1-650-324-9935 France SE-111 40 Stockholm Fax: +1-650-324-9936 COMSOL France Phone: +46 8 412 95 00 WTC, 5 pl.
    [Show full text]
  • Structural Vibration and Ways to Avoid It
    Structural Vibration and Ways to Avoid It Dynamic loadings take many forms. Two parameters can characterize such loadings: Their magnitude and their frequency content. Dynamic loadings can be replaced by static loadings when their frequency content is low compared to the natural frequency of the structure on which they are applied. Some people will refer as quasi-static analysis or loadings to remind themselves that they are actually predicting the effect of dynamic loadings treated as static equivalent. Most environmental loads (winds, earthquake, wave, transportation) can be replaced by quasi-static equivalents. When the frequency content of a dynamic loading and the natural frequencies of a structure are in the same range, then this approximation is no longer valid. This is the case for most machinery (compressors, pumps, engines, etc.) which produce loadings whose frequency content overlaps the natural frequencies of the structure on which they are mounted (platform, FPSO, etc.). In such a case, only a dynamic analysis will accurately predict the amplification of the response of the structure. Such loadings cannot be replaced by quasi-static equivalents. What makes these analyses even more challenging is the fact that the machinery, its equipment and the mounting skid cannot be seen as black boxes. They will interact with the foundation, the platform or the FPSO and the only way to know the magnitude of this interaction is to conduct a structural dynamic analysis that includes the foundation. This is a critical consideration which when overlooked considerably reduces the reliability of the machine and might even cause safety concerns. Structural Vibration and Resonance Structural vibration occurs when dynamic forces generated by compressors, pumps, and engines cause the deck beams to vibrate.
    [Show full text]
  • STRUCTURAL DYNAMICS Theory and Computation Fifth Edition STRUCTURAL DYNAMICS Theory and Computation Fifth Edition
    STRUCTURAL DYNAMICS Theory and Computation Fifth Edition STRUCTURAL DYNAMICS Theory and Computation Fifth Edition Mario Paz Speed Scientific School University ofLouisville Louisville, KY William Leigh University ofCentral Florida Orlando, FL . SPRINGER SCIENCE+BUSINESS MEDIA, LLC Library of Congress Cataloging-in-Publication Data Paz, Mario. Structural Dynamics: Theory and Computation I by Mario Paz, William Leigh.-5th ed. p.cm. Includes bibliographical references and index. Additional material to this book can be downloaded from http://extras.springer.com ISBN 978-1-4613-5098-9 ISBN 978-1-4615-0481-8 (eBook) DOI 10.1007/978-1-4615-0481-8 I. Structural dynamics. I. Title. Copyright© 2004 by Springer Science+Business Media New York Originally published by Kluwer Academic Publishers in 2004 Softcover reprint of the bardeover 5th edition 2004 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, mechanical, photo­ copying, recording, or otherwise, without the prior written permission of the publisher, Springer Science+Business Media, LLC. Pennission for books published in Europe: [email protected] Pennissions for books published in the United States of America: [email protected] Printedon acid-free paper. I tun/ ~ heloYed/~ anti,-~ heloYedw ~ J'he., SO"if' of SO"ft' CONTENTS PREFACE TO THE FIFTH EDITION xvii PREFACE TO THE FIRST EDITION xxi PART I STRUCTURES MODELED AS A SINGLE-DEGREE-OF-FREEDOM SYSTEM 1 1 UNDAMPED SINGLE-DEGREE-OF-FREEDOM SYSTEM 3
    [Show full text]
  • An Interdisciplinary Vibrations/Structural Dynamics Course for Civil and Mechanical Students with Integrated Hands on Laboratory
    2006-984: AN INTERDISCIPLINARY VIBRATIONS/STRUCTURAL DYNAMICS COURSE FOR CIVIL AND MECHANICAL STUDENTS WITH INTEGRATED HANDS-ON LABORATORY EXERCISES Richard Helgeson, University of Tennessee-Martin Richard Helgeson is an Associate Professor and Chair of the Engineering Department at the University of Tennessee at Martin. Dr. Helgeson received B.S. degrees in both electrical and civil engineering, an M.S. in electral engineering, and a Ph.D. in structural engineering from the University of Buffalo. He actively involves his undergraduate students in mutli-disciplinary earthquake structural control research projects. He is very interested in engineering educational pedagogy, and has taught a wide range of engineering courses. Page 11.202.1 Page © American Society for Engineering Education, 2006 An Interdisciplinary Vibrations/Structural Dynamics Course for Civil and Mechanical Students with Integrated Hands-on Laboratory Exercises Abstract The University of Tennessee at Martin offers a multi-disciplinary general engineering program with concentrations in civil, electrical, industrial, and mechanical engineering. In this paper the author discusses the development of an engineering course that is taken by both civil and mechanical engineering students. The course has been developed over a number of years, and during that time an integrated laboratory experience has been developed to support the unique interests of both groups of students. The course is required for all mechanical engineering students, while the civil engineering students may take the course as an upper division elective. To insure the success of the course, the author has structured the course to attract both groups of students. This paper discusses the course content and laboratory structure.
    [Show full text]
  • Ebook Download Structural Mechanics: Modelling and Analysis of Frames and Trusses 1St Edition
    STRUCTURAL MECHANICS: MODELLING AND ANALYSIS OF FRAMES AND TRUSSES 1ST EDITION PDF, EPUB, EBOOK Karl-Gunnar Olsson | 9781119159339 | | | | | Structural Mechanics: Modelling and Analysis of Frames and Trusses 1st edition PDF Book Nonlinear analysis using perturbation methods and classical elasticity W. View all copies of this ISBN edition:. These structures are usually indeterminate and the load causes generally bending of its members. The Ultimate Civil PE Breadth Exam Volume 1 and Volume 2 incorporates two question practice exams with detailed arrangements — assembled for acing the expansiveness part of the PE exam! Auxiliary and anxiety investigation is a center point in the scope of building controls — from basic designing through to mechanical and aeronautical designing and materials science. If you decide to participate, a new browser tab will open so you can complete the survey after you have completed your visit to this website. Connect with:. Olsson, Karl-Gunnar ; Dahlblom, Ola. Flag as inappropriate. He has in recent years also been a driving force behind renewal of literature and development of computer programs for teaching structural mechanics in the Bachelor of Science and Master of Science educations. You have entered an incorrect email address! In this way the body is able. Textbook covers the fundamental theory of structural mechanics and the modelling and analysis of frame and truss structures Deals with modelling and analysis of trusses and frames using a systematic matrix formulated displacement method with the language and flexibility of the finite element method Element matrices are established from analytical solutions to the differential equations Provides a strong toolbox with elements and algorithms for computational modelling and numerical exploration of truss and frame structures Discusses the concept of stiffness as a qualitative tool to explain structural behaviour Includes numerous exercises, for some of which the computer software CALFEM is used.
    [Show full text]
  • STRUCTURAL DYNAMICS and EARTHQUAKE ENGINEERING UNIT – I THEORY of VIBRATION Two Marks Questions and Answers 1
    V.S.B ENGINEERING COLLEGE, KARUR DEPARTMENT OF CIVIL ENGINEERING CE6701 – STRUCTURAL DYNAMICS AND EARTHQUAKE ENGINEERING UNIT – I THEORY OF VIBRATION Two Marks Questions and Answers 1. What is mean by Frequency? Frequency is number of times the motion repeated in the same sense or alternatively. It is the number of cycles made in one second (cps). It is also expressed as Hertz (Hz) named after the inventor of the term. The circular frequency ω in units of sec-1 is given by 2π f. 2. What is the formula for free vibration response? The vibration which persists in a structure after the force causing the motion has been removed. The corresponding equation under free vibration is mx + kx = 0 3. What are the effects of vibration? i. Effect on Human Sensitivity. ii. Effect on Structural Damage 4. Define damping. Damping is the resistance to the motion of a vibrating body. Damping is a measure of energy dissipation in a vibrating system. The dissipating mechanism may be of the frictional form or viscous form. Unit of damping is N/m/s. 5. What do you mean by Dynamic Response? The Dynamic may be defined simply as time varying. Dynamic load is therefore any load which varies in its magnitude, direction or both, with time. The structural response (i.e., resulting displacements and stresses) to a dynamic load is also time varying or dynamic in nature. Hence it is called dynamic response. 6. What is mean by free vibration? The vibration which persists in a structure after the force causing the motion has been removed is known free vibration.
    [Show full text]
  • Introduction to Structural Dynamics and Aeroelasticity: Second Edition Dewey H
    Cambridge University Press 978-0-521-19590-4 - Introduction to Structural Dynamics and Aeroelasticity: Second Edition Dewey H. Hodges and G. Alvin Pierce Frontmatter More information INTRODUCTION TO STRUCTURAL DYNAMICS AND AEROELASTICITY, SECOND EDITION This text provides an introduction to structural dynamics and aeroelasticity, with an em- phasis on conventional aircraft. The primary areas considered are structural dynamics, static aeroelasticity, and dynamic aeroelasticity. The structural dynamics material em- phasizes vibration, the modal representation, and dynamic response. Aeroelastic phe- nomena discussed include divergence, aileron reversal, airload redistribution, unsteady aerodynamics, flutter, and elastic tailoring. More than one hundred illustrations and ta- bles help clarify the text, and more than fifty problems enhance student learning. This text meets the need for an up-to-date treatment of structural dynamics and aeroelasticity for advanced undergraduate or beginning graduate aerospace engineering students. Praise from the First Edition “Wonderfully written and full of vital information by two unequalled experts on the subject, this text meets the need for an up-to-date treatment of structural dynamics and aeroelasticity for advanced undergraduate or beginning graduate aerospace engineering students.” – Current Engineering Practice “Hodges and Pierce have written this significant publication to fill an important gap in aeronautical engineering education. Highly recommended.” – Choice “...awelcomeadditiontothetextbooks available to those with interest in aeroelas- ticity....Asatextbook, it serves as an excellent resource for advanced undergraduate and entry-level graduate courses in aeroelasticity. ...Furthermore,practicingengineers interested in a background in aeroelasticity will find the text to be a friendly primer.” – AIAA Bulletin Dewey H. Hodges is a Professor in the School of Aerospace Engineering at the Georgia Institute of Technology.
    [Show full text]
  • Nodycon 2019 Program
    FIRST INTERNATIONAL NONLINEAR DYNAMICS CONFERENCE NODYCON 2019 PROGRAM Edited by The NODYCON 2019 Program Committee Department of Structural and Geotechnical Engineering Sapienza University of Rome First International Nonlinear Dynamics Conference Program, Rome, Italy, February 17-20, 2019 INSTITUTIONAL SPONSORS SPONSORS INFORMATION FOR CONFERENCE PARTICIPANTS PRESENTATION GUIDELINES Authors who present their work at technical sessions are expected to use the Conference laptops for their presentation. Each session room will be equipped with a projector with VGA or HDMI cables and a wireless presenter with laser pointer. Authors will be invited to upload their presentations through the dedicated web portal at www.nodycon2019.org. Prior to the session begins, authors are expected to check that their presentation is properly projected. Contributed presentations are 13- minute presentations plus 2 minutes for Q&A (15 mins). Please make sure that all presentations do not exceed these time limits. Plenary talks are 40-minute presentations plus 5 minutes for Q&A (45 mins). POSTER GUIDELINES For the Poster session, standard A0 posters in a free template are expected to be on display on the day of the Poster session. The presenting author is supposed to be available during the Poster session for Q&A. NODYCON 2019 APP An APP developed for iOS/Android ready for free download through Apple/Google stores will display the stream of conference news, the conference program with real-time updates, a tool to customize your conference agenda, maps for the conference rooms, likes on the talks/sessions, and the participants list. A few sample screenshots are shown below. 1 ALI H.
    [Show full text]