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