COMPOSITE STRUCTURES

2

Proceedings of the 2nd International Conference on Composite Structures, held at Paisley College of Technology, Scotland,from 14 to 16 September 1983, organised in association with the Scottish Development Agency and

the National Engineering Laboratory.

COMPOSITE STRUCTURES

2

Edited by

1. H. MARSHALL

Department of Mechanical and Production Engineering, Paisley College of Technology, Scotland

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British Library Cataloguing in Publication Data

International Conference on Composite Structures (2nd: 1983: Paisley College of Technology) Composite structures 2. I. Composite materials-Congresses 2. Composite construction--Congresses I. Title II. Marshall, I. H. 624.1'8 TA664

ISBN-13 : 978-94-009-6642-0 e-ISBN-13 : 978-94-009-6640-6 DO I : 10.1 007 / 978-94-009-6640-6

WITH 62 TABLES AND 309 ILLUSTRATIONS

© APPLIED SCIENCE PUBLISHERS LTD 1983

© CROWN COPYRIGHT 1983-Chapter 27

The selection and presentation of material and the opinions expressed in this publication are the sole responsibility of the authors concerned.

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, electronic, mechanical, photocopying, recording, or otherwise, without the prior

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Preface

The papers contained herein were presented at the Second International Conference on Composite Structures (ICCS/2) held at Paisley College of Technology, Paisley, Scotland, in September 1983. The Conference was organised and sponsored by Paisley College of Technology in association with the Scottish Development Agency and the National Engineering Laboratory. It forms a natural progression from the highly successful First International Conference on Composite Structures (lCCS/l) held at Paisley in September 1981.

The last few decades have seen phenomenal advances in research and development of composite materials with new and exciting structural possibilities being unearthed on an almost daily basis. Composites have been rightly heralded as space-age materials of the future. However, along with the rather specialised aerospace applications a growing awareness of the wider potential of composites is also unmistakable. The extensive composite materials research programmes of the fifties and sixties are now yielding fruit in abundance, with composites being used in virtually every area of structural engineering from transportation to pressure vessels and so on. Although significant weight savings, paramount in transportation engineering, are possible, composites have gone far beyond being simply lighter than conventional materials. They offer real structural advantages with almost unbounded potential. The ability to tailor a particular matrix material to suit prevailing environmental conditions whilst maintaining adequate reinforcement to withstand applied loading is unquestionably an attractive proposition.

There is growing evidence that today's advances in developing new v

vi Preface

composite materials are finding almost immediate practical applications in structural engineering. Composites can no longer be considered as rather specialised esoteric materials, only of interest to researchers in materials science. Rather, they have firmly established themselves as real and viable materials of construction with wide-ranging applications. A measurement of the rate of advance in structural engineering can be found by comparing the present volume with that pertaining to ICCS/I. In a space of only two years, tremendous strides are evident. With this in mind and with a conscious need for dissemination of knowledge between users, manu­facturers, designers and researchers involved in composite structural engineering, the present series of international conferences was organised.

Authors from fourteen countries combine with delegates from virtually every major industrial nation in the world to make this conference, once again, a truly international gathering of specialists in an ever-expanding technology. Topics under discussion range from performance studies in natural fibre composite structures to thermal control of composite structures in outer space.

An international conference can only succeed in making a contribution to knowledge through the considerable efforts of a number of enthusiastic and willing individuals. In particular, thanks are due to the following:

The Conference Steering Committee Professor J. Anderson Paisley College of Technology Dr W. S. Carswell National Engineering Laboratory J. Gleave Scottish Development Agency C. L. Phillips Scott-Bader Ltd Dr J. Rhodes University of Strathc1yde Dr E. J. Smith Pilkington Brothers Ltd J. A. Wylie Paisley College of Technology

The International Advisory Panel Dr E. Anderson Battelle Laboratories, Geneva (Switzerland) Dr W. M. Banks University of Strathc1yde (UK) Professor A. R. Bunsell Ecole des Mines de Paris (France) Professor T. Hayashi Chuo University, Tokyo (Japan) Professor R. M. Jones Virginia Polytechnic Institute and State

L. N. Phillips, OBE Professor S. W. Tsai

University (USA) Royal Aircraft Establishment (UK) Air Force Materials Laboratory, Ohio (USA)

Preface

The Local Organising Committee G. Macaulay J. S. Paul J. Kirk F. J. Allan The Conference Secretary, Mrs C. MacDonald.

vii

Grateful thanks are due to many other individuals who contributed to the success of this event. A final thanks to Nan, Simon and Louise for their support during the conference.

I. H. MARSHALL

Contents

Preface ....................................................................................... v

Session I: Plenary (Chairman: T. C. DOWNIE, Paisley College of Technology, Scotland)

I. The Monitoring of Damage in Carbon Fibre Composite Structures by Acoustic Emission ......................................... .

A. R. BUNSELL (Ecole Nationale Superieure des Mines de Paris, France)

2. Biaxial Failure of GRP-Mechanisms, Modes and Theories 21 M. J. OWEN (University of Nottingham, England)

Session II: Structural Monitoring (Chairman: W. S. CARSWELL, National Engineering Laboratory, East

Kilbride, Scotland)

3. Damage Detection in Carbon Fibre Epoxy Structures Using Acoustic Emission ............................................................... 40

D. VALENTIN and A. R. BUNSELL (Ecole Nationale Super ieu re des Mines de Paris, France)

4. Characterization of Composite Materials by Means of the Ultrasonic Stress Wave Factor ............................................ 53

J. C. DUKE Jr., E. G. HENNEKE, W. W. STINCHCOMB and K. L. REIFSNIDER (Virginia Polytechnic Institute and State University, Blacksburg, USA)

IX

x Contents

5. Acoustic Emission (AE) as a Tool for -Use on Composite Structures .......... .......... ........... .............. .......... ........... .......... 61

P. T. COLE (Endevco UK Ltd, Melbourn, England)

Session III: Structural Analysis: Platework Structures (Chairman: J. RHODES, University of Strathclyde, Glasgow, Scotland)

6. Axisymmetric Elastic Large Defie~tion Behaviour of Stiffened Composite Plates ................................................................. 72

G. J. TURVEY (University of Lancaster, England)

7. Vibration of Web-Stiffened Foam Sandwich Panel Structures 89 C. C. CHAO, C. C. WANG and C. Y. CHAN (National Tsing Hua University, Taiwan)

8. Global Transverse Shear in Laminated Composite Plates 102 R. GIRARD (Office National d' Etudes et de Recherches Aerospatiales, Chatillon, France)

Session IV: Vibration Studies (Chairman: T. FURUTA, National Aerospace Laboratory, Tokyo, Japan)

9. Vibration and Elastic Stability of Polar Orthotropic Variable Thickness Circular Plates Subjected to Hydrostatic Peripheral Loading ................................... ..... ............... ........ .... ............ 114

D. G. GORMAN (Queen Mary College, London, England)

10. A New Approach to the Nonlinear Dynamic Analysis of Composite Plates ..... ............. ....... .... ........... ..... ... ....... .. ....... . 128

M. SATHYAMOORTHY (Clarkson College of Technology, Potsdam, USA)

11. A Combined Experimental and Numerical Technique for the Determination of the Material Properties of Laminates ...... 136

J. L. WEARING and C. PATTERSON (University of Sheffield, England)

Contents xi

Session V: Finite Element Studies (Chairman: E. ANDERSON, Battelle Laboratories, Geneva, Switzerland)

12. Torsion of a Composite Beam ............................................. 146 J.-J. BARRAU and S. LAROZE (Ecole Nationale Superieure de I'Aeronautique et de I'Espace, Toulouse, France) and D. GAY (J NSA, Toulouse, France)

13. Elasto- Plastic Analysis of Fibrous Composite Shells Using 'Semiloof' Finite Elements ...... ..... .... ............. ........... ... ... ... ... ISS

S. MAKSIMOVIC (Vazduhoplovnotehnicki Institut, Belgrade, Yugoslada)

14. Failure Mechanisms and Strength Reduction in Composite Laminates with Cut-outs-A 3-D Finite Element Numerical Autopsy ............................................................................... 164

A. DE ROUVRAY, E. HAUG and J. DUBOIS (Engineering System International SA, Rungis, France)

Session VI: Structural Analysis: Structural Systems (Chairman: G. J. TURVEY, Unitwsity of Lancaster, England)

15. Structural Applications for Pultruded Profiles ........... .......... 192 T. F. STARR (Technolex, Crewkerne, England)

16 Large GRP Butterfly Valves ................................................ 214 M. H. BRYAN-BROWN and D. M. WALKER (Central Electricity Generating Board, Bristol, England)

17: Thermal Control of Tubular Composite Structures in Space Environment ........................................................................ 235

R. D. KARAM (Fairchild Space Company, Germantown, USA)

Session VII: Research and Development (Chairman: A. R. BUNSELL, I Ecole des Mines de Paris, France)

18. Simultaneous Elastic and Photoelastic Calibration of Birefringent Orthotropic Model Materials ........................... 249

R. PRABHAKARAN (Old Dominion UniL'ersity, Norfolk, USA)

xii Contents

19. The Effect of Moisture Absorption on Composite Laminates 260 C. S. WANG and G. C. CHANG (Chung-Shan Institute of Science and Technology, Taiwan)

20. The Nonlinear Viscoelastic Response of Resin Matrix Composites .......................................................................... 271

C. C. HIEL and H. F. BRINSON (Virginia Polytechnic Institute and State University, Blacksburg, USA) and A. H. CARDON (Free University of Brussels, Belgium)

Session VIII: Design (Chairman: W. M. BANKS, University of Strathclyde, Glasgow, Scotland)

21. Rotational Strength and Optimal Design of a Hybrid Filament-Wound Disc ........................................................................ 282

M. UEMURA, H. IYAMA and Y. FUKUNAGA (University of Tokyo, Japan)

22. Simplified Design Procedures for Composite Plates under Flexural Loading ................................................................. 302

A. F. JOHNSON and G. D. SIMS (National Physical Laboratory, Teddington, England)

23. Design Principles for Plastic Structures . ... .... ... ......... ... ... ..... 326 L. GARAY (Epitestudomanyi Intezet, Budapest, Hungary)

Session IX: Experimental Investigations (Joint Chairmen: H. F. BRINSON, Virginia Polytechnic Institute and State University, Blacksburg, U.S.A. and F. L. MATTHEWS, Imperial

College, London, England)

24. An Evaluation of the Impact Properties of Carbon Fibre Reinforced Composites with Various Matrix Materials ........ 332

AA. STORI and E. MAGNUS (Central Institute for Industrial Research, Oslo, Norway)

Contents xiii

25. Thermal Cycling and Vacuum Baking Effects on the Thermal Expansion of Graphite Fiber Reinforced Composite Laminates ............................................................................ 349

M. S. HENRIKSEN (Beckman Instruments, Brea, USA), P. D. ARTHUR, G. C. PARDOEN and H. DHARIN (University of California, Irvine and Berkeley, USA)

26. Testing Organic Composite Insulators for Fusion Magnets 364 H. BECKER, A. M. DAWSON, P. G. MARSTON and D. B. MONTGOMERY (Massachusetts Institute of Technology, Cambridge, USA)

27. A Comparison of Plain and Double Waisted Coupons for Static and Fatigue Tensile Testing of Unidirectional GRP and CFRP .................................................................................. 383

P. T. CURTIS and B. B. MOORE (Royal Aircraft Establish­ment, Farnborough, England)

Session X: Transportation Engineering (Chairman: E. J. SMITH, Pilkington Brothers Ltd, Ormskirk, England)

28. Sandwich Structures for Light Turrets .. ... ... ... ..... ... ... ...... ..... 399 R. W. McLAY, D. P. TAsSIEand W. W. THOMPSON (General Electric Company, Burlington, USA)

Session XI: Structural Analysis: Buckling Studies (Chairman: J. LOUGHLIN, Cranfield Institute of Technology, England)

29. A Study of the Buckling of Some Rectangular CFRP Plates 414 T. J. CRAIG and D. J. DAWE (University of Birmingham, England)

30. Postbuckling Behaviour of Cylindrically Curved Panels of Generally Layered Composite Materials with Small Imperfec-tions of Geometry ............................................................... 428

Y. ZHANG (Shenyang Aircraft Company, China) and F. L. MATTHEWS (Imperial College, London, England)

31. The Instability of Composite Channel Sections .................... 442 W. M. BANKS and J. RHODES (University of Strathciyde, Glasgow, Scotland)

XIV Contents

Session XII: Failure Analysis (Chairman: M. J. OWEN, University of Nottingham, England)

32. Analysis of a Hybrid Unidirectional Buffer Strip Laminate. 453 L. R. DHARANI (University of Missouri, Rolla, USA) and J. G. GOREE (Clemson University, Clemson, USA)

33. Basic Failure Mechanisms of Laminated Composites and Related Aircraft Design Implications ................................... 467

R. C. SANDERS, E. C. EDGE and P. GRANT (British Aerospace, Warton Division, England)

Session XIII: Fracture Mechanics (Chairman: J. ANDERSON, Paisley College of Technology, Scotland)

34. The i-Integral as a Fracture Criterion for Composite Materials ............................................................................. 486

B. D. AGARWAL, P. KUMAR and B. S. PATRO (Indian Institute of Technology, Kanpur, India)

35. Fracture of a Bimaterial Plate with a Crack Along the Interface .............................................................................. 500

E. E. GDOUTOS (Democritus University of Thrace, Xanthi, Greece)

36. The Effects of Laminate Thickness on the Fracture Behavior of Composite Laminates .. ... ... ....... ... .... .... ...... .............. ............ 511

C. E. HARRIS and D. H. MORRIS (Virginia Polytechnic Institute and State University, Blacksburg, USA)

Session XIV: Feasibility Studies including Natural Fibre Composites (Chairman: C. L. PHILLIPS, Scott Bader Co. Ltd, Wellingborough,

England)

37. The Suitability of Fibre-Cement Composites for Reinforcing Adobe Structures in Earthquake Zones ............................... 525

D. G. SWIFT (Kenyatta University College, Nairobi, Kenya), R. B. L. SMITH and K. S. RANGASAMI (University of Nairobi, Kenya)

Contents xv

38. Performance of Banana Fabric-Polyester Resin Composites 535 K. G. SATYANARAYANA, K. SUKUMARAN, A. G. KULKARNI, S. G. K. PILLAI and P. K. ROHA TGI (Council of Scientific and Industrial Research, Trivandrum, India)

39. Comparative Study on the Incorporation of Composite Material for Tyre Computation ........................................... 549

H. ROTHERT and BA NGUYEN (University of Hannoz:er, West Germany) and R. GALL (Hochschule der Bundeswehr Hamburg, West Germany)

Index ......................................................................................... 569