Plasticity - Mathematical Theory and Numerical Analysis swDSV1alMB
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by Weimin Han B. Daya Reddy eXU;UO^
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Springer 1999 A/U tf0{3"
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The basis for the modern theory of elastoplasticity was laid in the nineteenthcentury, [^gSWU
by Tresca, St. Venant, L´evy, and Bauschinger. Further '7F`qL\/#(
major advances followed in the early part of this century, the chief contributors [)gvP'
during this period being Prandtl, von Mises, and Reuss. This Q#bFW?>y,
early phase in the history of elastoplasticity was characterized by the introduction iDO~G($C
and development of the concepts of irreversible behavior, yield hfvs'.
criteria, hardening and perfect plasticity, and of rate or incremental constitutive _e_]$G/TM
equations for the plastic strain. b'N"?W^YQ
Greater clarity in the mathematical framework for elastoplasticity theory _OF8D
came with the contributions of Prager, Drucker, and Hill, during the (WW,]#^
period just after the Second World War. Convexity of yield surfaces, and a<V=C
all its ramifications, was a central theme in this phase of the development V,uhBMT#
of the theory. _W:
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The mathematical community, meanwhile, witnessed a burst of progress WPE@yI(
in the theory of partial differential equations and variational inequalities ubhem(p#
from the early 1960s onwards. The timing of this set of developments was +{/zP{jH
particularly fortuitous for plasticity, given the fairly mature state of the 'Ph4(Yg
subject, and the realization that the natural framework for the study of X/1Z9a+W
initial boundary value problems in elastoplasticity was that of variational q\[31$i$
inequalities. This confluence of subjects emanating from mechanics and @ %z5]w
mathematics resulted in yet further theoretical developments, the outstanding zYOPE 6E
examples being the articles by Moreau, and the monographs |k'I?:'
by Duvaut and J.-L. Lions, and Temam. In this manner the stage was {kJ[) 7
set for comprehensive investigations of the well-posedness of problems in
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elastoplasticity, while the simultaneous rapid growth in interest in numer- <,0&Ox
ical methods ensured that equal attention was given to issues such as the tS2lex%
development of solution algorithms, and their convergences. 2|~&x~
The interaction between elastoplasticity and mathematics has spawned 2597#O
among many engineering scientists an interest in gaining a better understanding nm'm*sU\
of the modern mathematical developments in the subject. In the t:M({|m Y
same way, given the richness of plasticity in interesting and important r _r$nl
mathematical problems, many mathematicians, either students or mature q9Y0Lk
researchers, have developed an interest in understanding the mechanical ^d"tymDd
and engineering basis of the subject, and its connections with the mathematical #%e`OA(b
theory. While there are many textbooks and monographs on plasticity U2ANu|
that deal with the mechanics of the subject, they are written mainly LM _4.J
for a readership in the engineering sciences; there does not appear to us j.CC.[$g
to have existed an extended account of elastoplasticity which would serve Yb =8\<;
these dual needs of both engineering scientists and mathematicians. It is i=2+1;K
our hope that this monograph will go some way towards filling that gap. UsQv!Cwu^
We present in this work three logically connected aspects of the theory of NUL~zb
elastic-plastic solids: the constitutive theory, the variational formulations of hJ:Hv.{`)W
the related initial boundary value problems, and the numerical analysis of VH*j3
these problems. These three aspects determine the three parts into which y&__2t^u
the monograph is divided. TF^]^XS'
The constitutive theory, which is the subject of Part I, begins with a wCvD4C.WH
motivation grounded in physical experience, whereafter the constitutive *OF7{^~&
theory of classical elastoplastic media is developed. This theory is then cast 73xI8
in a convex analytic setting, after some salient results from convex analysis @V :b Co
have been reviewed. The term “classical” refers in this work to that theory q#\eL~k
of elastic-plastic material behavior which is based on the notion of convex n.lp
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yield surfaces, and the normality law. Furthermore, only the small strain, n?,fF(
quasi-static theory is treated. Much of what is covered in Part I will be GZ'hj_2%<
familiar to those working on plasticity, though the greater insights offered {/7'uD\
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by exploiting the tools of convex analysis may be new to some researchers. Mdwh-Cis/
On the other hand, mathematicians unfamiliar with plasticity theory will lQ+-g#`
find in this first part an introduction that is self-contained and accessible. C-6+ZIk4
Part II of the monograph is concerned with the variational problems in `%ymg8^
elastoplasticity. Two major problems are identified and treated: the primal 00pHnNoxW
problem, of which the displacement and internal variables are the primary u gfV'
unknowns; and the dual problem, of which the main unknowns are the n?
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generalized stresses. 1xtbhk]D
Finally, Part III is devoted to a treatment of the approximation of the gdC=SFb b
variational problems presented in the previous part. We focus on finite element "Pys3=h
approximations in space, and both semi- and fully discrete problems. 1<R
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In addition to deriving error estimates for these approximations, attention ^ O`
is given to the behavior of those solution algorithms that are in common nMc-kyl{
use. m dC. FO-
Wherever possible we provide background materials of sufficient depth j#p3c
to make this work as self-contained as possible. Thus, Part I contains a 6
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Preface ix gieX`}
review of topics in continuum mechanics, thermodynamics, linear elasticity, :,VyOmf
and convex analytic setting of elastoplasticity. In Part II we include a 3YT _GW{
treatment of those topics from functional analysis and function spaces that d'-^VxO0
are relevant to a discussion of the well-posedness of vatriational problems. \O/=g6w|t}
And Part III begins with an overview of the mathematics of finite elements. BLJ-'8G
In writing this work we have drawn heavily on the results of our joint collaboration Vr0RdO
in the past few years. We have also consulted, and made liberal x@k9]6/zs
use of the works of many: we mention in particular the major contributions rfPJBD{Ve
of G. Duvaut and J.-L. Lions, C. Johnson, J.B. Martin, H. /|DQ_<*
Matthies, and J.C. Simo. While we acknowledge this debt with gratitude, jY?%LY@5I
the responsibility for any inaccuracies or erroneous interpretations Vk_L*lcN
that might exist in this work, rests with its authors. 2dI:],7
We thank our many friends, colleagues and family members whose interest, #-VKk
guidance, and encouragement made this work possible. \|&5eeE@
W.H. 9Pb0Olh
Iowa City uPp(l4(+
B.D.R. E{Q^ZSV3B
Cape Town