Plasticity - Mathematical Theory and Numerical Analysis $aU.M3
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by Weimin Han B. Daya Reddy K/Pw;{}
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Springer 1999 tw.GBR
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The basis for the modern theory of elastoplasticity was laid in the nineteenthcentury, NZZy^p&O
by Tresca, St. Venant, L´evy, and Bauschinger. Further :JX2GRL4
major advances followed in the early part of this century, the chief contributors M:oM(K+
during this period being Prandtl, von Mises, and Reuss. This i5Sya]FN
early phase in the history of elastoplasticity was characterized by the introduction Sx
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and development of the concepts of irreversible behavior, yield Iw.!*0$
criteria, hardening and perfect plasticity, and of rate or incremental constitutive 1,h:|
equations for the plastic strain. |cnps$fk~
Greater clarity in the mathematical framework for elastoplasticity theory X=1o$:7
came with the contributions of Prager, Drucker, and Hill, during the ZI1]B944ni
period just after the Second World War. Convexity of yield surfaces, and N2HD=[*cr
all its ramifications, was a central theme in this phase of the development e-v|
of the theory. 2z#S|$
The mathematical community, meanwhile, witnessed a burst of progress ,W[J@4.
in the theory of partial differential equations and variational inequalities f@Jrbg
from the early 1960s onwards. The timing of this set of developments was
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particularly fortuitous for plasticity, given the fairly mature state of the xk/-TXB
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subject, and the realization that the natural framework for the study of &L+.5i
initial boundary value problems in elastoplasticity was that of variational ;a>u7rw
inequalities. This confluence of subjects emanating from mechanics and ?aWVfX!+G5
mathematics resulted in yet further theoretical developments, the outstanding Ua:@,};
examples being the articles by Moreau, and the monographs -G/qfd|s/
by Duvaut and J.-L. Lions, and Temam. In this manner the stage was }.'rhR+
set for comprehensive investigations of the well-posedness of problems in Fx.Ly]L
elastoplasticity, while the simultaneous rapid growth in interest in numer- 2ry@<88
ical methods ensured that equal attention was given to issues such as the t_!p({
development of solution algorithms, and their convergences. 4'`P+p"A
The interaction between elastoplasticity and mathematics has spawned ?ZGsh7<k
among many engineering scientists an interest in gaining a better understanding _[E+D0A
of the modern mathematical developments in the subject. In the `V<jt5TS
same way, given the richness of plasticity in interesting and important 1|w@f&W"
mathematical problems, many mathematicians, either students or mature gd7r9yV
researchers, have developed an interest in understanding the mechanical QD3tM5(Yr
and engineering basis of the subject, and its connections with the mathematical _#r00Ze
theory. While there are many textbooks and monographs on plasticity bW!
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that deal with the mechanics of the subject, they are written mainly O9>$(`@I
for a readership in the engineering sciences; there does not appear to us ))Z>$\<:
to have existed an extended account of elastoplasticity which would serve f@hM ^%
these dual needs of both engineering scientists and mathematicians. It is vR!g1gI23
our hope that this monograph will go some way towards filling that gap. c'3N;sZ*B
We present in this work three logically connected aspects of the theory of p[xGL }
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elastic-plastic solids: the constitutive theory, the variational formulations of ,YvOk|@R
the related initial boundary value problems, and the numerical analysis of |kvH`&s
these problems. These three aspects determine the three parts into which /i27F2NQm
the monograph is divided. +'5I8FE-
The constitutive theory, which is the subject of Part I, begins with a Z- a
motivation grounded in physical experience, whereafter the constitutive Q~0>GOq*
theory of classical elastoplastic media is developed. This theory is then cast Djc-f
in a convex analytic setting, after some salient results from convex analysis u;t~
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have been reviewed. The term “classical” refers in this work to that theory U+>M@!=
of elastic-plastic material behavior which is based on the notion of convex -8FUR~WJ
yield surfaces, and the normality law. Furthermore, only the small strain, b+:J?MR;}
quasi-static theory is treated. Much of what is covered in Part I will be Nb9GrYIS
familiar to those working on plasticity, though the greater insights offered .QKyB>s
by exploiting the tools of convex analysis may be new to some researchers. #|,cy,v4
On the other hand, mathematicians unfamiliar with plasticity theory will >P@VD"U
find in this first part an introduction that is self-contained and accessible. H
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Part II of the monograph is concerned with the variational problems in T^`; wD
elastoplasticity. Two major problems are identified and treated: the primal ^<-r57pz
problem, of which the displacement and internal variables are the primary R)*DkL!
unknowns; and the dual problem, of which the main unknowns are the @q>Hl`a
generalized stresses. -L]-u6kC[
Finally, Part III is devoted to a treatment of the approximation of the M!i|,S
variational problems presented in the previous part. We focus on finite element 1|"BpX~D
approximations in space, and both semi- and fully discrete problems. GrJLQO0$N
In addition to deriving error estimates for these approximations, attention x$o^;2Z
is given to the behavior of those solution algorithms that are in common &V~l(1
use. b FajK;
Wherever possible we provide background materials of sufficient depth =$)M-;6
to make this work as self-contained as possible. Thus, Part I contains a 6YNL4HE?
Preface ix \$.{*f
review of topics in continuum mechanics, thermodynamics, linear elasticity, qF`6l(
and convex analytic setting of elastoplasticity. In Part II we include a MIr+4L
treatment of those topics from functional analysis and function spaces that =z"+)N
are relevant to a discussion of the well-posedness of vatriational problems. M.s'~S7y
And Part III begins with an overview of the mathematics of finite elements. !dGu0wE
In writing this work we have drawn heavily on the results of our joint collaboration *IWW,@0
in the past few years. We have also consulted, and made liberal (?t}S.>g
use of the works of many: we mention in particular the major contributions w$9LcN
of G. Duvaut and J.-L. Lions, C. Johnson, J.B. Martin, H. +e2:?d@
Matthies, and J.C. Simo. While we acknowledge this debt with gratitude, <,GVrVH=t"
the responsibility for any inaccuracies or erroneous interpretations Q0K$ZWM`7
that might exist in this work, rests with its authors. 3Ji$igL
We thank our many friends, colleagues and family members whose interest, .?QYqGcG
guidance, and encouragement made this work possible. ^Z;zA@[wt
W.H. $F#
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