Table Of ContentDIANA Computational Mechanics '94
DIANA
Computational Mechanics '94
PROCEEDINGS OF THE FIRST
INTERNATIONAL DIANA CONFERENCE
ON COMPUTATIONAL MECHANICS
Edited by
GER M.A. KÜSTERS
TNO Building and Construction Research /
DIANA Foundation,
Delfl, The Netherlands
and
MAX A.N. HENDRIKS
TNO Building and Construction Research,
Delfl, The Netherlands
SPRINGER SCIENCE+BUSINESS MEDIA, B.V.
A CLP. Catalogue record for this book is available from the Library of Congress
ISBN 978-94-010-4454-7 ISBN 978-94-011-1046-4 (eBook)
DOI 10.1007/978-94-011-1046-4
Printed on acid-free paper
All Rights Reserved
© 1994 Springer Science+Business Media Dordrecht
Originally published by Kluwer Academic Publishers in 1994
Softcover reprint of the hardcover 1 st edition 1994
No part of the material protected by this copyright notice may be reproduced or
utilized in any form or by any means, electronic or mechanical,
including photocopying, recording or by any information storage and
retrieval system, without written permission from the copyright owner.
CONTENTS
Preface ix
INVITED PAPERS
SomeFutureDirections inComputational FailureMechanics
R.deBorst, J. Carmeliet, J. Pamin, L.J. Sluys 1
RecentDevelopmentsinNonlinearDynamicsofMechanical Systems
DB.van Campen, A.deKraker, E.L.B.vandeVorst, J.A.W. vanderSpek 13
TheLossoftheSleipnerCondeepPlatform
I. Holand 25
ComputinginEngineeringPractice whatwill theFutureHold?
C. Meyer 37
NonlinearAnalysisofReinforcedConcrete Members underHighTemperature
A.Mutoh, N. Yamazaki 45
Concrete Mechanics AspectsasBackgroundforStructural Modeling
H.W Reinhardt, J. Oibolt 57
ATopological Approach toModeling Arbitrary CrackPropagation in3D
P.A. Wawrzynek, B.J. Carter, A.R./ngraffea, D.O. Potyondy 69
MATERIAL MODELING
TheEstimationofMaterial ParametersofaFluid-SolidMixture
O.M.G.c. opden Camp, J.G.A. vanHouten, C.W.J. Oomens, F.E. Veldpaus,
J.D. Janssen, J.J. Kok 85
OnStochastic Descriptions forDamageEvolution inQuasi-Brittle Materials
J. Carmeliet 93
TheDelftEggModel,aConstitutive ModelforClay
S.J.M. vanEekelen, P. vanden Berg 103
OnStructural AnalysisofRoadPavements
T. Gartung 117
ViscousRegularization ofStrain-Localisation forDamagingMaterials
M.G.D. Geers, W.A.M. Brekelmans, R.deBorst 127
AFiniteElementFormulation ofMuscleContraction
A.W.J. Gielen, PB.M. Bovendeerd, J.D. Janssen 139
v
vi
SizeEffectPredictionsbyFractureModelsforaRefractory Ceramic
M.A.J. vanGils, L.J.M.G.Dortmans, G. de With, W.A.M. Brekelmans, J.H.P. de Vree..149
PorousMediaMechanics
J.M. Huyghe, G.B. Houben, J.D. Janssen, J. Vankan, H. Snijders 159
AScalarDamageModel AppliedtoConcrete
M. Polanco-Loria, S.l. Serensen 171
TheModellingofFiniteDeformationElasticity andPlasticity
J.C.J. Schellekens, H. Parisch 181
DynamicFailureinReinforcedConcrete Structures
L.J.Sluys 193
FE-SimulationoftheWedge-Splitting TestonHighStrengthConcrete (HSC)
R. Zeitler, J.D. Worner 205
FINITE ELEMENT TECHNOLOGY
Application andExperimental Verification ofDIANAforAcousto-Elastic Problems
w.M. Beltman, P.J.M. vanderHaagt, R.M.E.J.Spiering, H. Tijdeman 215
Numerical SimulationofFormingProcesses,UsinganArbitrary Lagrangian Eulerian
FiniteElementMethod
A.H. vandenBoogaard, J. Huetink 225
ConsistentFormulationofaTriangularFiniteRotation Shel1Element
J. Booij, F. vanKeulen 235
Three-DimensionalElastoplastic Calculations Utilising DifferentElementTypes
A.E.Groen 245
FiniteElementReliability MethodsUsing DIANA
M.A. Gutierrez, J. Carmeliet, R.deBorst 255
ADIANA-ElementfortheDynamicAnalysisofLaminatePlates
F.P. Groateman, J. Locht, P.J.M. vanderHaogt, R.M.E.J.Spiering, H. Tijdeman.........265
Reliable Recovery ofStressResultants
T. Kvamsdal, K.M. Mathisen 277
Mode-Reduction Applied toInitial Post-Buckling Behaviour
G.M.A.Schreppers, C.M. Menken 287
vii
SOLUTION PROCEDURES
ClusteringofElementsinEBE-Preconditioners
M.B. vanGijzen 297
AlgorithmsfortheParallel DirectSolutionofSparseLinearSystems
P.Nauta 307
ENGINEERING COMPUTATIONS
DesignandAnalysisofaPrestressedConcreteBoxGirder
A.deBoer,N. Kaptijn, M. Naaktgeboren 321
Punching ShearofReinforced ConcretePlates
T. Dyngeland, K.V. Hoiseth, E. Opheim 329
ExtremeBendingofConcreteCoated OffshorePipelines
G.Erukll 339
AnalysesofShear-WallPanelswithaCompositePlasticity Model
P.H. Feenstra, R.deBorst, J.G. Rots 349
AssessmentofaStrategy forthe DetailedAnalysisofMasonry Structures
P.E.Lourenfo,J.G. Rots, J. Blaauwendraad 359
FEAnalysisinRoadPavementDesignintheNetherlands
W. vanSchelt, E. Vos 371
StudyofSteelBarCorrosion byExperimental andAnalytical Simulation
P. Siwiec, P. Stroeven, A.T. Moczko 383
3DNonlinearAnalysisofCompositeSlabs
M. Veljkovic 395
Author Index 405
PREFACE
To make further advances in computational mechanics, fruitful discussion is required
between researchers and practising engineers. It is intended that the present DIANA
conference on computational Mechanics will be ofspecial interest to those involved in
new developments incomputational mechanics, as well as those whoareinterested in the
widefieldofitsapplications.
Thefollowing domainsaretheobjectofpresentations anddiscussions:
• (hyper)-elasticity,(visco-)plasticity andcracking;
• (enriched) damagingcontinuamodels;
• material experiments versuscomputational models;
• stochastic approaches;
• fluid-structure interaction;
• elementtechnology;
• geometrical nonlinearity andstructural instability;
• nonlineardynamics;
• solution procedures.
Typical fields of application are: (reinforced) concrete structures, steel-concrete
structures, forming processes, biomechanics, soil mechanics, road mechanics, ceramics,
and composite materials. Besidesthis volumecontains severalinvitedpapersofareview
nature. With a few exceptions the papers show calculation results which are achieved
withtheDIANAT'"FiniteElementsystem.
Thearrangementofthis volumeisindicated bythecontents. Basically wefollow theline
from research on material level via research on element level to research on structural
level. It is emphasized however that nowadays many research projects in the field of
computational mechanics are not limited to one ofthese levels. We observe a growing
interaction between the research on the above levels. Areas like identification and
optimalization exemplify this type of research for the coming years. Consequently the
subdivisionofthis volumeshouldbeseen in thesamebroadperspective.
Asco-organizers ofthe conference we wish to expressourcordial thankstothechairman
and keynote speakers for accepting our invitations. We also thank our colleagues who
have kindly accepted the invitations topresent their workat this firstinternational DIANA
conference and to prepare their papers for inclusion in these proceedings. Financial
support from the sponsors is gratefully acknowledged. We hope that the readers ofthe
"First International DIANA conference on computational Mechanics" will find a state-of
the-science invariousareas incomputational mechanics, itstheory anditsapplications.
GerKusters andMaxHendriks
Delft,June 1994
T"':DIANAisaregistered trademarkOfTNO.
IX
x
CONFERENCECHAIRMAN CO-SPONSORS
Prof.JohanBlaauwendraad .IaJ
ING BANK
DelftUniversity ofTechnology
TheNetherlands
KEY-NOTESPEAKERS
Prof.R.deBorst
DelftUniversity ofTechnology
TheNetherlands
Prof.D.H.vanCampen
Eindhoven UniversityofTechnology
TheNetherlands
F4n-.
HEWLETT
Prof.I.Holand a=~PACKARC
SINTEFStructuresandConcrete
Norway
Prof.A.R.Ingraffea
CornellUniversity
USA
Prof.C.Meyer
DIANA
ColumbiaUniversity
USA ONTWIKKEUHGSYEllEHIGING
Dr.A.Mutoh
ShimizuCorporation
Japan
Prof.H.W.Reinhardt
UniversityofStuttgart
Germany
ORGANIZINGCOMMITTEE
111111
WillemJ.E. vanSpanje
DIANAAnalysis bv
GerM.A. Kusters
DIANAFoundation .Hi
TUDelft
HansJongedijk
DIANAUsersAssociation
MaxA.N.Hendriks ".. .
,f).. ", - , ..
TNOBuilding andConstruction Research
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SOMEFUTURE DIRECTIONSIN
COMPUTATIONALFAILUREMECHANICS
R. DEBORST!,J. CARMELIET2,J. PAMINandL.J. SLUYS
Delft University ofTechnology, FacultyofCivil Engineering,
PO. Box5048, 2600GADelft, TheNetherlands
Abstract. Continuumapproachesarereviewedwhichcanproperlymodellocaliseddeforma
tions that act as a precursor to final fracture in quasi-brittle materials. Next, one such
higher-orderdamagingcontinuummodel iscombinedwitha stochasticapproachtodescribe
theheterogeneityinquasi-brittlematerials.
Keywords:Softening,localisation,finiteelementanalysis,randomfields
1. Introduction
Failure in quasi-brittle and frictional materialsinvolves localisation ofdefor
mation, i.e., we observe that at incipient failure small zones of highly
strained material develop abruptly while the remainder ofthe body experi
ences virtually no additional straining. Examples are cracks in concrete,
shear bands in soils and rock faults. Experiments show that these localisa
tion phenomenona are accompanied by a sharp decrease ofthe load-carrying
capacity. This phenomenon is commonly named strain softening and leads to
ill-posed boundary value problems in standard continuum theories, since in
quasi-static problems ellipticity ofthe governing set ofdifferential equations
is lost and in dynamic problems hyperbolicity is lost. In numerical simula
tions this leads to anextrememeshsensitivityin termsoffineness and direc
tion ofthegridlines. Toremedy this improperbehaviourthestandardcontin
uum model must be enriched by adding higher-order terms, either spatially
orin the timedomain. Thesetechniques arecommonlyreferred to as regular
isation methods. In this contribution we shall scrutinise the possibilities of
usingenriched continuum theories (non-local and gradienttheories) to reme
dy this deficiency ofthe standard continuum. For dynamic problems the pos
sibility ofaddingviscosity to the constitutive model will also be investigated.
Finiteelementanalysesarepresentedtoillustratesomeofthe approaches.
I. AlsoatEindhovenUniversityofTechnology,FacultyofMechanicalEngineering
2. OnleavefromCatholicUniversityofLeuven,DepartmentofCivilEngineering
I
GMA.KustersandMAN.Hendriks(eds.).DIANAComputationalMechanics'94.1-12.
©1994KluwerAcademicPublishers.
2
Another important property ofthese materials is the inherent heterogeneity
at a relatively large scale. This heterogeneity may imply that the exact fail
ure mode can be highly dependent upon the precise flaw distribution. To
model this inhomogeneity stochastic material properties must be assumed in
numericalsimulations. However, the use ofa stochasticapproach does notre
solve the above mentioned issue ofthe change ofcharacter ofthe governing
differential equations during progressive damage. A simulation technique
that describes the true failure process properlywithin the framework ofcon
tinuum mechanics must incorporate both a regularisation of the standard
continuum during progressivedamage and a stochastic strengthdistribution.
This statement will be substantiated in this contribution. To do so we will
present finite element analyses of direct tension tests with a local damage
model andwith a nonlocal damage model. In bothcases deterministic as well
as stochasticcalculations usinga MonteCarlotechnique will be presentedfor
two different levels ofdiscretisation. The randomness in the damage process
will be introduced byconsideringthe initial damage as a univariate homoge
neous random field, describing the continuous spatial distribution and the
autocorrelation.
2. Cracking,damageandlocalisationofdeformation
The essentialdeficiencyofthestandard continuum modelcan be demonstrat
ed simply by the example ofa simple barloaded in uniaxial tension [1]. Let
the barbedivided intom elements. Now supposethatoneelementhas a ten
sile strength that is marginally below that ofthe other m- 1elements. Upon
reaching the tensile strength ofthis element failure will occur. In the other,
neighbouringelements the tensile strength is not exceeded and they will un
load elastically. The result in terms ofthe displacementofthe end ofthe bar
is fully dominated bythe discretisation, and convergence to a 'true' post-peak
failure curve does not seem to occur. In fact, it does occur, as the failure
mechanism in a standard continuum is a line crackwith zero thickness. The
finite element solutionofourcontinuum rate boundaryvalue problem simply
tries to capture this line crack, which results in localisation in one element,
irrespective of the width of this element. The result on the load-average
strain curve is obvious: for an infinite number ofelements (m~00) the post
peak curve doubles back on the original loading curve. Numerous numerical
examples for allsorts ofmaterials existwhich further illustrate the above ar
gument. From a physical point ofview the above behaviour is unacceptable
and when we adhere to continuum descriptions one must enrich the continu
um by adding higher-order terms, either in space or in time, which can ac
commodatenarrow zonesofhighlylocaliseddeformations.
2.1 Thefracture-energy'trick'
As an intermediate solution between using the standard continuum model
