\documentclass[reqno]{amsart} \usepackage{hyperref} \AtBeginDocument{{\noindent\small {\em Electronic Journal of Differential Equations}, Vol. 2006(2006), No. 137, pp. 1--11.\newline ISSN: 1072-6691. URL: http://ejde.math.txstate.edu or http://ejde.math.unt.edu \newline ftp ejde.math.txstate.edu (login: ftp)} \thanks{\copyright 2006 Texas State University - San Marcos.} \vspace{8mm}} \begin{document} \title[\hfilneg EJDE-2006/137\hfil A property of the $H$-convergence] {A property of the $H$-convergence for elasticity in perforated domains} \author[H. Haddadou\hfil EJDE-2006/137\hfilneg] {Hamid Haddadou} \address{Hamid Haddadou \newline Institut Nationale de formation en Informatique, BP 68, Oued Smar, El Harrach, Alger, Alg\'{e}rie} \email{h\_haddadou@ini.dz} \date{} \thanks{Submitted July 6, 2006. Published October 31, 2006.} \subjclass[2000]{35B40, 74B05} \keywords{Homogenization; H-convergence; linearized elasticity system; \hfill\break\indent perforated domains} \begin{abstract} In this article, we obtain the $H_{e}^{0}$-convergence as a limit case of the $H_{e}$-convergence. More precisely, if $\Omega_{\varepsilon}$ is a perforated domain with (admissible) holes $T_{\varepsilon}$ and $\chi_{\varepsilon}$ denote its characteristic function and if $(A^{\varepsilon},T_{\varepsilon})\overset{H_{e}^{0}}{\rightharpoonup}A^{0}$, we show how the behavior as $(\varepsilon,\delta)\to(0,0)$ of the double sequence of tensors $A^{\varepsilon}_{\delta}=(\chi_{\varepsilon}+\delta(1-\chi_{\varepsilon})) A^{\varepsilon}$ is connected to $A^{0}$. These results extend those given by Cioranescu, Damlamian, Donato and Mascarenhas in \cite{ciodam} for the $H$-convergence of the scalar second elliptic operators to the linearized elasticity systems. \end{abstract} \maketitle \numberwithin{equation}{section} \newtheorem{theorem}{Theorem}[section] \newtheorem{definition}[theorem]{Definition} \newtheorem{lemma}[theorem]{Lemma} \newtheorem{proposition}[theorem]{Proposition} \newtheorem{remark}[theorem]{Remark} \section{Introduction} The notion of $H$-convergence was introduced by Murat and Tartar \cite{mur,murta,tar} for the second-order elliptic operators (non necessary symmetric) and extended to the case of holes by Briane, Damlamian and Donato in \cite{bri} and called $H^{0}$-convergence. Cioranescu, Damlamian, Donato and Mascarenhas \cite{ciodam} obtain the $H^{0}$-convergence as a limit case of the $H$-convergence with a vanishing coercivity constant in the holes. In this work, we show that a similar property holds for the linearized elasticity systems, namely between the $H_{e}$-convergence studied by Francfort and Murat in \cite{fra} and its generalization to the case of holes, denoted by $H_{e}^{0}$-convergence, which has been developed by Donato and El Hajji in \cite{don}. The $H_{e}$-convergence deals with the convergence of the solutions of a system of linearized elasticity whose tensor coefficients $\{A^{\varepsilon}\}$ are equibounded and uniformly definite positive. The $H_{e}^{0}$-convergence treat the same problem in a perforated domain $\Omega_{\varepsilon}$ with a traction condition on the holes for which uniform Korn estimates hold. Let us briefly describe here the main results of this paper. Let $\Omega$ a bounded open subset of $\mathbb{R}^{n}$, $\{T_{\varepsilon}\}$ a sequence of (admissible) holes, denote $\Omega_{\varepsilon}=\Omega\setminus T_{\varepsilon}$ the perforated domain and $\chi^{\varepsilon}$ the characteristic function of $\Omega_{\varepsilon}$. Let also $\{A^{\varepsilon }\}$ a sequence of linearized elasticity tensors on $\Omega$ such that $(A^{\varepsilon},T_{\varepsilon})\overset{H_{e}^{0}}{\rightharpoonup}A^{0}$. We prove (Theorem \ref{li10}) that if we set for every $\delta>0$ $$ A^{\varepsilon}_{\delta}=(\chi_{\varepsilon}+\delta(1-\chi_{\varepsilon})) A^{\varepsilon}\quad\text{ a.e. in }\Omega $$ and if $A^{\varepsilon}_{\delta}$ $H_{e}$-converges to a tensor $A_{\delta}$ (for some subsequence), then $A_{\delta} \to A^{0}$ strongly in $L^{p}(\Omega)$ for any $p\geq1$, and weakly $\star$ in $L^{\infty}(\Omega)$. Moreover, under suitable assumption (see \eqref{e22} below), we have also (Theorem \ref{li11}) \begin{equation*} (A_{\delta}^{\varepsilon} \overset{\delta\to0}{\longrightarrow} (A^{\varepsilon},T_{\varepsilon} ))\text{ in the sense }\left\{ \begin{array}{l} u^{\varepsilon}_{\delta}\to u^{\varepsilon}\text{ strongly in } H^{1}_{0}(\Omega_{\varepsilon})^{n},\\[3pt] A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})\to A^{\varepsilon} \widetilde{e(u^{\varepsilon})}\text{ strongly in } \;L^{2}(\Omega)^{n\times n} \end{array} \right. \end{equation*} and (Theorem \ref{li12})\begin{equation*} (A^{\varepsilon}_{\delta}\overset{(\varepsilon,\delta)\to(0,0)}{\longrightarrow} A^{0})\text{ in the sense }\left\{ \begin{array}{l} u^{\varepsilon}_{\delta}\to u^{0}\text{ weakly in } H^{1}_{0}(\Omega)^{n},\\ A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})\to A^{0}e(u^{0})\text{ weakly in }L^{2}(\Omega)^{n\times n}, \end{array} \right. \end{equation*} where $u^{\varepsilon}$, $u^{\varepsilon}_{\delta}$ and $u^{0}$ are the solutions of \eqref{e2}, \eqref{e9} and \eqref{e4} respectively. This results can be resumed by the following commutative schema: \begin{equation*} \begin{array}{ccc} A^{\varepsilon}_{\delta} & \overset{H_{e}}{\rightharpoonup}&A_{\delta} \\ \downarrow & \searrow& \downarrow\; \\ (A^{\varepsilon},T_{\varepsilon} )& \overset{H_{e}^{0}}{\rightharpoonup} & A^{0}. \\ \end{array} \end{equation*} The definition and the main properties of the $H_{e}^{0}$-convergence are recalled in Section 2. In Section 3 we give some preliminary results and in Section 4 we state and prove the main results. \section{The $H_{e}^{0}$-convergence} We use the following notation:\\ $\bullet$ If $A =(A _{ijkl}) _{1\leq i,j,k,l\leq n}$ is a forth order tensors and $\Lambda\in\mathbb{R}^{n\times n}$, we set \begin{gather*} A\Lambda=\sum_{1\leq i,j,k,l\leq n} A_{ijkl} \Lambda_{pq},\\ \Lambda.\Upsilon=\sum_{1\leq i,j\leq n}\Lambda_{ij}\Upsilon_{ij},\\ |\Lambda|= (\sum_{1\leq i,j\leq n} |\Lambda_{ij}|^{2})^\frac{1}{2}, \end{gather*} $\bullet$ $\Omega $ is a domain of $\mathbb{R}^{n}$,\\ $\bullet$ if $F$ is a set of matrices fields, $F_{S}=\{M\in F\;s.\;t.\;M\;is \;symmetric\}$,\\ $\bullet$ $\{\varepsilon\} $ and $\{\delta\} $ denote a two strictly decreasing sequence converging to zero, \newline $\bullet$ if ${v} =({v} _{1}, $\dots $, {v} _{n})$ is a vector valued function and $\zeta =( \zeta _{ij})_{1\leq i, j\leq n}$ is a second order tensor of variable $x=(x_{1}, $\dots , $x_{n})$, we set \begin{gather*} ( \nabla {v} ) _{ij}=\frac {\partial v_{i}}{ \partial x_{j}}\equiv D_{x_{j}}v_{i}, \\ e({v} )=\frac{1}{2}(\nabla {v} +^{t}\nabla {v} ), \\ ( \mathop{\rm div}\xi )_{i}=\frac{\partial \xi _{ij}}{ \partial x_{j}}; \end{gather*} $\bullet$ for two real numbers $\alpha $ and $\beta$ such that $0<\alpha <\beta $, $M_{e}( \alpha , \beta , \Omega) $ is the set of the tensors $A=( A_{ijkl}) _{1\leq i, j, k, l\leq n}$ defined on $\Omega$, such that a.e. on $\Omega$ we have \begin{itemize} \item[(i)] $A_{ijkl}\in L^{\infty }( \Omega)$, for any $i, j, k, l=1,\dots , n$, \item[(ii)] $A_{ijkl}=A_{jikl}=A_{klij}$, for any $i, j, k,l=1,\dots , n $, \item[(iii)] $\alpha | \Lambda | ^{2}\leq A\Lambda .\Lambda$, for any symmetric matrix $\Lambda$, \item[(iv)] $| A\Lambda|\leq \beta | \Lambda|$, for any matrix $\Lambda$, \end{itemize} $\bullet$ if $f\in H^{-1}(\Omega)^{n}$ and $u\in H^{1}_{0}(\Omega)^{n}$, we set $\langle f,u\rangle=\langle f,u\rangle _{H^{-1}(\Omega)^{n},H^{1}_{0}(\Omega)^{n}}$. Let us recall first the main results concerning the $H^{0}_{e}$-convergence introduced by Donato and El Hajji \cite{don}. We introduce the perforated domain \begin{equation*} \Omega_{\varepsilon}=\Omega \backslash T_{\varepsilon}, \end{equation*} where $T_{\varepsilon}$ is a sequence of compact subsets of $\Omega$ and set \begin{equation*} V_{\varepsilon}=\{ v \in H^{1}( \Omega_{\varepsilon}) ^{n} \text{ s. t. $v=0$ on }\partial \Omega\}. \end{equation*} In the following, we denote by $\nu $ the outward normal unit vector on the boundary of $\Omega _{\varepsilon}$ and $\widetilde{.}$ the extension by 0 from $\Omega_{\varepsilon}$ to $\Omega $ and set $\chi^{\varepsilon}=\chi _{_{\Omega _{\varepsilon}}}$. \begin{definition}[\cite{don}]\label{li1} \rm The set $T_{\varepsilon}$ is said to be admissible (in $\Omega )$ for the linearized elasticity (or e-admissible), if and only if: \begin{itemize} \item[(i)] Every $L^{\infty }$ weak $\ast $-limit point of $\{ \chi _{_{\Omega _{\varepsilon}}}\} _{\varepsilon}$ is positive a.e. in $\Omega $; \item[(ii)] there exists a positive real $C$, independent of ${\varepsilon} $, and a sequence $\{ P_{\varepsilon}\} _{\varepsilon}$ of linear extension operators such that for each ${\varepsilon} $ \begin{equation}\label{e1} \begin{gathered} P_{\varepsilon}\in \mathcal{L}(V_{\varepsilon}, H_{0}^{1}(\Omega )^{n}), \\ ( P_{\varepsilon}v ) |_{\Omega_{\varepsilon}}={v} ,\quad \forall {v} \in V_{\varepsilon}, \\ \|e( P_{\varepsilon}v ) \| _{0,\Omega}\leq C\|e({v} )\| _{0, \Omega _{\varepsilon}}, \quad \forall {v} \in V_{\varepsilon}. \end{gathered} \end{equation} \end{itemize} \end{definition} We denote by $P_{\varepsilon}^{\star }$ the adjoint operator of $P_{\varepsilon}$, which is defined from $H^{-1}(\Omega)^{n}$ to $V'_{\varepsilon}$ with $P_{\varepsilon}^{\star }$ given for every $f\in H^{-1}(\Omega) ^{n}$ by \begin{equation*} \forall v\in V_{\varepsilon},\;\langle P_{\varepsilon}^{\star}f,v\rangle_{V'_{\varepsilon},V_{\varepsilon}}= \langle f,P_{\varepsilon}v\rangle_{H^{-1}(\Omega)^{n},H_{0}^{1}(\Omega)^{n}}. \end{equation*} \begin{definition}[\cite{don}]\label{li2} \rm Let $ A^{{\varepsilon} }\in M_{e}( \alpha , \beta , {\Omega}) $, $T_{\varepsilon}$ be e-admissible in $\Omega $. The pair $(A^{{\varepsilon} }, T_{\varepsilon})$ is said $H_{e}^{0}$-converge to the tensor $A^{0}\in M_{e}( \alpha ', \beta ', \Omega) $ and denoted by $(A^{{\varepsilon} }, T_{\varepsilon}) \overset{H_{e}^{0}}{\rightharpoonup }A^{0}$ if and only if for each function $f^{\varepsilon}\in H^{-1}(\Omega)^{n}$ such that $f^{\varepsilon}\to f$ strongly in $H^{-1}(\Omega)^{n}$, the solution $u^{\varepsilon}$ of \begin{equation}\label{e2} \begin{gathered} -\mathop{\rm div}\;(A^{{\varepsilon} }e( u^{{\varepsilon} }) )=P_{\varepsilon}^{\star }f^{\varepsilon}\quad\text{in }\Omega _{\varepsilon}, \\ (A^{{\varepsilon} }e( u^{{\varepsilon} }) )\nu =0\quad \text{on } \partial T_{\varepsilon}, \\ u^{{\varepsilon} }=0\quad\text{on }\partial \Omega , \end{gathered} \end{equation} satisfies the weak convergence \begin{equation}\label{e3} \begin{gathered} P_{\varepsilon}(u^{{\varepsilon} }){ \rightharpoonup }u^{0}\quad \text{weakly in }H_{0}^{1}(\Omega )^{n}, \\ A^{{\varepsilon} }\widetilde{e( u^{{\varepsilon} }) } { \rightharpoonup }A^{0}e(u^{0})\quad \text{weakly in } L^{2}(\Omega )^{n\times n}, \end{gathered} \end{equation} where $u^{0}$ is the unique solution of the problem \begin{equation}\label{e4} \begin{gathered} -\mathop{\rm div}(A^{0}e( u^{0}) )=f\quad\text{in }\Omega ,\\ u^{0}=0\quad\text{on }\partial \Omega. \end{gathered} \end{equation} \end{definition} \begin{remark}\label{li3} \rm (1) In \cite{don} the definition is given for fixed $f_{\varepsilon}\doteq f$. The two definitions are equivalent in view of \cite[Proposition 2]{don}.\\ (2) In the case where $T_{\varepsilon}=\emptyset$, this definition reduces to the definition of the $H_{e}$-convergence \cite{fra}. \end{remark} This notion of convergence makes sense in view of the following compactness theorem: \begin{theorem}[\cite{don}] \label{li4} Let $A^{{\varepsilon} }\in M_{e}( \alpha , \beta , \Omega) $ and $T_{\varepsilon}$ be e-admissible in $\Omega $. Then there exists a subsequence, still denoted by $\{\varepsilon\}$, and a tensor $A^{0}\in M_{e}(\frac{\alpha}{C^{2}}, \beta , {\Omega})$, such that the sequence $\{ (A^{{\varepsilon} }, T_{\varepsilon})\} _{\varepsilon}$ $H_{e}^{0}$-converge to $A^{0}$. \end{theorem} \begin{remark}\label{li5} \rm The fact that $A^{0}$ belongs to $M_{e}( \frac{\alpha}{C^{2}}, \beta , {\Omega}) $, does not appears explicitly in the statement given in \cite{don}, but can be easily deduced with the same arguments as that used in the non perforated case. \end{remark} Let us recall also a property proved recently in \cite{do-ha}. \begin{theorem}[\cite{do-ha}] \label{li6bis} Let $\{A^{\varepsilon }\}\in \mathcal{M}_{e}( \alpha , \beta ,\Omega)$ and $\{B^{\varepsilon}\}\in \mathcal{M}_{e}( \alpha' , \beta ',\Omega)$ such that $A^{\varepsilon}\overset{H_{e}}{\rightharpoonup}A^{0}$ and $B^{\varepsilon}\overset{H_{e}}{\rightharpoonup}B^{0}$. Assume that there exists two functions $h^{\varepsilon},\;h^{0}\in L^{1}(\Omega)$ such that \begin{equation*} |A^{\varepsilon}-B^{\varepsilon}|\leq h^{\varepsilon}\longrightarrow h^{0}\quad\text{strongly in }L^{1}(\Omega). \end{equation*} Then \begin{equation*}|A^{0}(x)-B^{0}(x)|\leq \sqrt{\frac {\beta\beta'}{\alpha\alpha'}}\;h^{0}(x)\quad\text{a.e. in } \Omega. \end{equation*} \end{theorem} The following proposition completes a result given in \cite{don}: \begin{proposition} \label{li6} One has \begin{enumerate} \item If $\{v ^{\varepsilon}\}$ is a bounded sequence in $H^{1}_{0}(\Omega)$, then \begin{equation*} ( v ^{\varepsilon}\;\rightharpoonup \; v \text{ weakly in } H_{0}^{1}(\Omega )^{n}) \Leftrightarrow \Big(P_{\varepsilon}({v^{\varepsilon} } |_{\Omega_{\varepsilon}} ) \;\rightharpoonup \; {v} \text{ weakly in } H_{0}^{1}(\Omega )^{n}\Big). \end{equation*} \item If $(\varepsilon,\delta)$ is a sequence of $\mathbb{R}_{+}^{\star}\times\mathbb{R}_{+}^{\star}$ such that $(\varepsilon,\delta)\to(0,0)$ and $\{v ^{\varepsilon}_{\delta}\}$ is a sequence in $H^{1}_{0}(\Omega)$ bounded independently of $\varepsilon$ and $\delta$, then \begin{equation*} ( v ^{\varepsilon}_{\delta}\;\rightharpoonup \; v \text{ weakly in }H_{0}^{1}(\Omega )^{n}) \Leftrightarrow \Big( P_{\varepsilon}({v^{\varepsilon}_{\delta}} |_{\Omega _{\varepsilon}} ) \;\rightharpoonup \; {v} \text{ weakly in } H_{0}^{1}(\Omega )^{n}\Big). \end{equation*} \end{enumerate} \end{proposition} \begin{proof} Suppose that \begin{equation}\label{e4bis2} P_{\varepsilon}({v^{\varepsilon} } |_{\Omega _{\varepsilon}} ){ \;\rightharpoonup \; }{v} \quad \text{weakly in } H_{0}^{1}(\Omega )^{n}. \end{equation} Observe first that \begin{equation}\label{e4bis1} v^{\varepsilon}\chi^{\varepsilon}=P_{\varepsilon}({v^{\varepsilon}} _{| _{\Omega _{\varepsilon}}})\chi^{\varepsilon}. \end{equation} On the other hand, since $\{v ^{\varepsilon}\}$ is a bounded sequence in $H^{1}_{0}(\Omega)$, there exists a $\{\varepsilon'\}\subset\{\varepsilon\}$ and $w\in H_{0}^{1}(\Omega )^{n}$ such that \begin{equation}\label{e4bis3} v^{\varepsilon'}\rightharpoonup w\quad\text{weakly in } H_{0}^{1}(\Omega)^{n}. \end{equation} But $|\chi^{\varepsilon'}|\leq 1$, hence there exists $\chi^{0}\in L^{\infty}(\Omega)$ and $\{\varepsilon''\}\subset \{\varepsilon'\}$ such that \begin{equation}\label{e4bis4} \chi^{\varepsilon''}\rightharpoonup \chi^{0}\quad \text{weakly $\star$ in }L^{\infty}(\Omega). \end{equation} Passing to the limit (in $D'(\Omega)$) in (\ref{e4bis1}) by using (\ref{e4bis2}), (\ref{e4bis3}) and (\ref{e4bis4}), we find $$ \chi^{0}w=\chi^{0}v. $$ Taking now into account the fact that (in view of Definition \ref{li1}) $\chi^{0}>0$, we obtain $w=v$. This, together with (\ref{e4bis3}), implies that the whole sequence $P_{\varepsilon}({v_{\delta}^{\varepsilon}} _{| _{\Omega _{\varepsilon}}})$ converge weakly to $v$. We refer to \cite{don} for the converse implication. The proof of (2) follows by the same arguments. \end{proof} \section{Preliminary results} In this paper, $\{A^{\varepsilon}\}$ is a sequence of fourth-order tensors of $\mathcal{M}_{e}(\alpha,\beta,\Omega)$ and $\{T_{\varepsilon}\}$ is a sequence of holes e-admissible in $\Omega$ such that \begin{equation}\label{e5} A^{\varepsilon}\overset{H^{0}_{e}}{\rightharpoonup}A^{0}. \end{equation} Set, for every $\delta>0$, \begin{equation}\label{e6}A^{\varepsilon}_{\delta}=(\chi_{\varepsilon}+\delta(1-\chi_{\varepsilon})) A^{\varepsilon}\quad\text{a.e. in }\Omega. \end{equation} Since, for fixed $\delta>0$, $A^{\varepsilon}_{\delta}\in\mathcal{M}_{e}(\min(1,\delta)\alpha, \max(1,\delta)\beta,\Omega)$, in view of the compactness properties of $H_{e}$-convergence, there exists a subsequence $ \{\varepsilon_{m}\}$ of $\{\varepsilon\}$ and $A_{\delta}\in\mathcal{M}_{e}(\min(1,\delta)\alpha,\max(1,\delta)\beta,\Omega)$ such that $A_{\delta}^{\varepsilon_{m}}\overset{H_{e}}{\rightharpoonup}A_{\delta}$ as $\varepsilon_{m}\to0.$ Hence, for every $\delta>0$, the set \begin{equation}\label{e7} W_{\delta}=\{A_{\delta} ;\;\exists\{\varepsilon_{m}\}_{m\in\mathbb{N}}\subset\{\varepsilon\} \text{ s. t. } A_{\delta}^{\varepsilon_{m}}\overset{H_{e}}{\rightharpoonup}A_{\delta}\}\\ \end{equation} is not empty. Let $\{f^{\varepsilon}\}$ be a sequence in $H^{-1}(\Omega)^{n}$ such that \begin{equation}\label{e8}f^{\varepsilon}\to f\\quad \text{strongly in } H^{-1}(\Omega)^{n} \end{equation} and let $A_{\delta}$ be in $ W_{\delta}$. Let $u^{\varepsilon}_{\delta}$ and $u_{\delta}$ the solutions of \begin{equation}\label{e9} \begin{gathered} -\mathop{\rm div}(A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta}) )=f^{\varepsilon}\quad\text{in } \Omega, \\ u^{\varepsilon}_{\delta}=0\quad\text{on }\partial\Omega \end{gathered} \end{equation} and \begin{equation}\label{e10} \begin{gathered} -\mathop{\rm div}(A_{\delta}e(u_{\delta}) )=f\quad\text{in } \Omega, \\ u_{\delta}=0\quad\text{on }\partial\Omega \end{gathered} \end{equation} respectively. We consider now the following sets: \begin{equation}\label{e11} \begin{gathered} U_{\delta}=\{u_{\delta}: u_{\delta}\text{ is the solution of \eqref{e10} for some }A_{\delta}\in W_{\delta}\},\\ V_{\delta} =\{\text{The set of weak limit points of } A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta}) \text{ in $L^{2}(\Omega)^{n}$ as $\varepsilon\to 0$}\}. \end{gathered} \end{equation} One has the following result: \begin{lemma}\label{li7} One has $$ V_{\delta}=\{A_{\delta}e(u_{\delta}) : A_{\delta}\in W_{\delta}\text{ and $u_{\delta}$ is the solution of \eqref{e10}}\}. $$ \end{lemma} \begin{proof} It is clear that, if $ A_{\delta}\in W_{\delta}$ and $u_{\delta}$ is the solution of \eqref{e10}, then $A_{\delta}e(u_{\delta})$ belongs to $V_{\delta}$. On the other hand, let $v\in V_{\delta}$. Then, there exists a subsequence $\{\varepsilon_{m}\}$ of $\varepsilon$ such that \begin{equation}\label{e12} A^{\varepsilon_{m}}_{\delta}e(u^{\varepsilon_{m}}_{\delta})\rightharpoonup v\quad\text{weakly in }L^{2}(\Omega)^{n}, \end{equation} as $\varepsilon_{m}\to0$. But the compactness property of the $H_{e}$-convergence shows that there exists a subsequence $\{\varepsilon'_{m}\}$ of $\{\varepsilon_{m}\}$ and a forth-order tensor $A_{\delta}$ such that $$ A_{\delta}^{\varepsilon'_{m}}\overset{H_{e}}{\rightharpoonup}A_{\delta}. $$ This implies in particular $$ A^{\varepsilon'_{m}}_{\delta}e(u^{\varepsilon'_{m}}_{\delta})\rightharpoonup A_{\delta}e(u_{\delta})\quad\text{weakly in }L^{2}(\Omega)^{n}. $$ This, together with (\ref{e12}), gives $v=A_{\delta}e(u_{\delta})$. \end{proof} \begin{remark}\label{e12bis} \rm Let us show that in view of Theorem \ref{li6bis}, there exists $\{\varepsilon_{m}\}\subset\{\varepsilon\}$ and for all $\delta>0$ a tensor $\widehat{A_{\delta}}$ such that \begin{equation} \label{e12bis0} A_{\delta}^{\varepsilon_{m}}\overset{H_{e}}{\rightharpoonup} \widehat{A_{\delta}}. \end{equation} Let us also point out that in Theorem \ref{li10} we will consider a more general situation, where for every $\delta>0$, there exists $\{\varepsilon_{\delta}\}$ and a tensor $A_{\delta}$ such that $A_{\delta}^{\varepsilon_{\delta}}\overset{H_{e}}{\rightharpoonup}A_{\delta}$. \end{remark} Let us prove (\ref{e12bis0}). Using the diagonal subsequence procedure and the compactness property of the $H_{e}$-convergence, one extracts a subsequence $\{\varepsilon_{m}\}$ of $\{\varepsilon\}$ such that, for every $\delta\in\mathbb{Q}^{\star}_{+}$, one has \begin{equation}\label{e12bis1} A^{\varepsilon_{m}}_{\delta} \;H_{e}\text{-convergences to a limit }A_{\delta}. \end{equation} Since a.e in $\Omega$ one has \begin{gather*} |A^{\varepsilon_m}_{\delta_{1}}-A^{\varepsilon_m}_{\delta_{2}}|\leq \beta|\delta_{1}-\delta_{2}|,\quad \forall \delta_{1},\;\delta_{2}\in\mathbb{Q}^{\star}_{+},\\ A^{\varepsilon_m}_{\delta_{1}}\in\mathcal{M}_{e}(\min(1,\delta_{1})\alpha, \max(1,\delta_{1})\beta,\Omega),\\ A^{\varepsilon_m}_{\delta_{2}}\in\mathcal{M}_{e}(\min(1,\delta_{2})\alpha, \max(1,\delta_{2})\beta,\Omega). \end{gather*} Then, from Theorem \ref{li6bis}, it follows \begin{equation*} |A_{\delta_{1}}-A_{\delta_{2}}|\leq \frac{\beta^{2}}{\alpha}\; \sqrt{\frac{\max(1,\delta_{1})\max(1,\delta_{2})}{\min(1,\delta_{1}) \min(1,\delta_{2})}}\;|\delta_{1}-\delta_{2}|. \end{equation*} This implies that the mapping $\delta\in\mathbb{Q}^{\star}_{+}\mapsto A_{\delta}\in\mathbb{L}^{\infty}(\Omega)$ is uniformly continuous. Hence, it can be extended to a mapping (still denoted by $\delta\mapsto A_{\delta}$) defined and uniformly continuous on all $\mathbb{R}^{\star}_{+}$ (since $\mathbb{Q}^{\star}_{+}$ is dense in $\mathbb{R}^{\star}_{+}$). Let now $\delta$ be a strictly positive real and $\{\delta_{s}\}$ be a sequence of $\mathbb{Q}^{\star}_{+}$ which converges to $\delta$ as $s\to\infty$. Then, there exists a sub-subsequence $\{\varepsilon'_{m}\}$ of $\{\varepsilon_{m}\}$ such that \begin{equation}\label{e12bis2} A^{\varepsilon'_{m}}_{\delta}\;H_{e}\text{-converges to some }A. \end{equation} In view of Theorem \ref{li6bis} this give, together with (\ref{e12bis1}) and the fact that $|A^{\varepsilon'_{m}}_{\delta}-A^{\varepsilon'_{m}}_{\delta_{s}}|\leq \beta|\delta-\delta_{s}|$, the following inequality: \[ |A-A_{\delta_{s}}|\leq \frac{\beta^{2}}{\alpha}\;\sqrt{\frac{\max(1,\delta)\max(1,\delta_{s})} {\min(1,\delta)\min(1,\delta_{s})}}\;|\delta-\delta_{s}|\quad \text{a.e. in } \Omega. \] Using the continuity of the mapping $\delta\mapsto A_{\delta}$ on $\mathbb{R}^{\star}_{+}$ and passing to the limit in this inequality as $s\to\infty$, one finds \begin{equation*} A=A_{\delta},\quad\text{a.e. in }\Omega. \end{equation*} The uniqueness of the limit implies then that the whole subsequence $A^{\varepsilon_{m}}_{\delta}$ $H_{e}$-converges to $A_{\delta}$, for every $\delta>0$. The following results state some a priori estimates that we will need in the following: \begin{proposition}\label{li8} Let $u^{\varepsilon}$ and $u^{\varepsilon}_{\delta}$ the solutions of \eqref{e2} and \eqref{e9} respectively. Then, there exists $c>0$ independent of $\varepsilon$ and $\delta$ such that \begin{equation}\label{e13} \begin{gathered} \|P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}) -P^{\varepsilon}u^{\varepsilon} \|_{H^{1}_{0}(\Omega)^{n}} \leq c(\delta^{1/2}+|\langle f_{\varepsilon},P^{\varepsilon}({u^{\varepsilon}_{\delta}}_ {|_{\Omega_{\varepsilon}}})-u_{\delta}^{\varepsilon}\rangle|^{1/2} ),\\ \|e(u^{\varepsilon}_{\delta})\|_{L^{2}(T_{\varepsilon})^{n\times n}} \leq c(1+\delta^{^{-\frac{1}{2}}}|\langle f_{\varepsilon},P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_ {\varepsilon}}})-u_{\delta}^{\varepsilon}\rangle|^{1/2} ),\\ \|A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})-A^{{\varepsilon} }\widetilde{e( u^{{\varepsilon} }) }\ \|_{L^{2}(\Omega)^{n\times n}} \leq c(\delta^{1/2}+|\langle f_{\varepsilon},P^{\varepsilon}({u^{\varepsilon}_{\delta}}_ {|_{\Omega_{\varepsilon}}})-u_{\delta}^{\varepsilon}\rangle|^{1/2}). \end{gathered} \end{equation} \end{proposition} \begin{proof} Observe that the variational formulations of problems \eqref{e2} and \eqref{e9} are \begin{equation}\label{e13bis} \forall w\in H^{1}_{0}(\Omega)^{n},\;\;\;\int_{\Omega_{\varepsilon}} A^{\varepsilon}e(u^{\varepsilon}).e(w)dx=\langle f_{\varepsilon},P^{\varepsilon}(w_{|_{\Omega_{\varepsilon}}})\rangle \end{equation} and \begin{equation*} \forall w\in H^{1}_{0}(\Omega)^{n},\;\int_{\Omega_{\varepsilon}} A^{\varepsilon}e(u^{\varepsilon}_{\delta}).e(w)dx+ \delta\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}).e(w)dx=\langle f_{\varepsilon},w\rangle \end{equation*} respectively. Then, for every $w\in H^{1}_{0}(\Omega)^{n}$, one has \begin{equation*} \int_{\Omega_{\varepsilon}} A^{\varepsilon}(e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon})).e(w)dx+ \delta\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}).e(w)dx=-\langle f_{\varepsilon},P^{\varepsilon}(w_{|_{\Omega_{\varepsilon}}})-w\rangle .\end{equation*} In particular, for $w=u^{\varepsilon}_{\delta}-P^{\varepsilon}u^{\varepsilon}$, this gives \begin{align*} &\int_{\Omega_{\varepsilon}} A^{\varepsilon}(e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon})). (e(u^{\varepsilon}_{\delta})-e(P^{\varepsilon}u^{\varepsilon}))dx+ \delta\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}). (e(u^{\varepsilon}_{\delta})-e(P^{\varepsilon}u^{\varepsilon}))dx\\ &=-\langle f_{\varepsilon},P^{\varepsilon}((u^{\varepsilon}_{\delta} -P^{\varepsilon}u^{\varepsilon})_{|_{\Omega_{\varepsilon}}}) -u^{\varepsilon}_{\delta}-P^{\varepsilon}u^{\varepsilon}\rangle. \end{align*} Using that ${P^{\varepsilon}u^{\varepsilon}} _{|_{\Omega_{\varepsilon}}}=u^{\varepsilon}$, one deduces \begin{align*} &\int_{\Omega_{\varepsilon}} A^{\varepsilon}(e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon})). (e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon}))dx+ \delta\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}). e(u^{\varepsilon}_{\delta})dx\\ &=\delta\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}). e(P^{\varepsilon}u^{\varepsilon})dx-\langle f_{\varepsilon},P^{\varepsilon}(u^{\varepsilon}_{\delta}) _{|_{\Omega_{\varepsilon}}}-u^{\varepsilon}_{\delta}\rangle. \end{align*} In view of the fact that $A^{\varepsilon}\in M_{e}(\alpha, \beta, {\Omega})$, this gives \begin{equation}\label{e13bis1} \begin{aligned} &\alpha\int_{\Omega_{\varepsilon}} |e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon}))|^{2}dx +\alpha\delta\int_{T_{\varepsilon}} |e(u^{\varepsilon}_{\delta})|^{2}dx\\ &\leq \delta|\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}). e(P^{\varepsilon}u^{\varepsilon})dx|+|\langle f_{\varepsilon},P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})-u^{\varepsilon}_{\delta}\rangle|. \end{aligned} \end{equation} Using the Young's inequality, one obtains \begin{align*} \big|\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}).e(P^{\varepsilon} u^{\varepsilon})dx\big| &\leq \beta\int_{T_{\varepsilon}}|e(u^{\varepsilon}_{\delta})| |e(P^{\varepsilon} u^{\varepsilon})|dx\\ &\leq \frac{\alpha}{2}\int_{T_{\varepsilon}} |e(u^{\varepsilon}_{\delta})|^{2}dx+ \frac{\beta^{2}}{2\alpha}\int_{T_{\varepsilon}} |e(P^{\varepsilon}u^{\varepsilon})|^{2}dx\\ &\leq \frac{\alpha}{2}\int_{T_{\varepsilon}}|e(u^{\varepsilon}_{\delta})|^{2}dx + \frac{\beta^{2}}{2\alpha}\int_{\Omega}|e(P^{\varepsilon}u^{\varepsilon})|^{2} dx. \end{align*} But, taking $w=P^{\varepsilon}u^{\varepsilon}$ in (\ref{e13bis}), one finds $$ \int_{\Omega}|e(P^{\varepsilon}u^{\varepsilon})|dx\leq c_{1}, $$ with $c_{1}>0$ independent of $\varepsilon$ and $\delta$. Then \begin{equation*} \big|\int_{T_{\varepsilon}}A^{\varepsilon}e(u^{\varepsilon}_{\delta}) .e(P^{\varepsilon} u^{\varepsilon})dx\big| \leq \frac{\alpha}{2}\int_{T_{\varepsilon}}|e(u^{\varepsilon}_{\delta})|^{2}dx+ c_{2}, \end{equation*} where $c_{2}>0$ independent of $\varepsilon$ and $\delta$. This, together with (\ref{e13bis1}), gives \begin{equation}\label{e14} \alpha\int_{\Omega_{\varepsilon}} |e(u^{\varepsilon}_{\delta})-e(u^{\varepsilon}))|^{2}dx+\frac{\alpha\delta}{2}\int_{T_{\varepsilon}} |e(u^{\varepsilon}_{\delta})|^{2}dx\leq c_{3}(\delta+|\langle f_{\varepsilon},P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})-u^{\varepsilon}_{\delta}\rangle|). \end{equation} with $c_{3}>0$ independent of $\varepsilon$ and $\delta$. From this, \eqref{e13}ii) follows immediately. Moreover, since ${u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}-u^{\varepsilon}\in H^{1}_{0}(\Omega_{\varepsilon})^{n}$, Definition \ref{li1} shows that $$ \|e(P^{\varepsilon}({u^{\varepsilon}_{\delta}}{|_{\Omega_{\varepsilon}}} -u^{\varepsilon}))\|_{0,\Omega}\leq C \|e(u^{\varepsilon}_{\delta}-u^{\varepsilon})\|_{0,\Omega_{\varepsilon}}. $$ Hence, by virtue of the Korn inequality, (\ref{e14}) gives also \eqref{e13}i).\medskip\\ On the other hand, since $A^{\varepsilon}_{\delta}=A^{\varepsilon}$ a.e. in $\Omega_{\varepsilon}$ and $A^{\varepsilon}_{\delta}=\delta A^{\varepsilon}$ a.e. in $T_{\varepsilon}$, one has \begin{align*} \int_{\Omega} |A_{\delta}^{\varepsilon}e(u^{\varepsilon}_{\delta}) -A^{\varepsilon}\widetilde{e(u^{{\varepsilon} }) }|^{2} dx &\leq \int_{\Omega_{\varepsilon}} |A^{\varepsilon}e(u^{\varepsilon}_{\delta})-A^{\varepsilon}e( u^{{\varepsilon} })|^{2} dx+\delta^{2}\int_{T_{\varepsilon}}|A^{\varepsilon}e(u^{\varepsilon}_{\delta})|^{2} dx\\ &\leq \beta^{2}\int_{\Omega_{\varepsilon}} |e(u^{\varepsilon}_{\delta})-e( u^{{\varepsilon} })|^{2} dx+\beta^{2}\delta^{2}\int_{T_{\varepsilon}}|e(u^{\varepsilon}_{\delta})|^{2}dx, \end{align*} which, together with \eqref{e13}(i) and \eqref{e13}(ii), gives \eqref{e13}(iii). \end{proof} \begin{proposition}\label{li9} Let $u^{0}$ the solution of \eqref{e4}. Then \begin{equation}\label{e15} \begin{gathered} \sup_{u\in U_{\delta}} \|u-u^{0} \|_{H^{1}_{0}(\Omega)^{n}} \leq c\;\delta^{1/2},\\ \sup_{v\in V_{\delta}}\|v-A^{0}e(u^{0})\|_{L^{2}(\Omega)^{n\times n}} \leq c\;\delta^{1/2} . \end{gathered} \end{equation} \end{proposition} \begin{proof} Let be $u_{\delta}$ in $ U_{\delta}$. This means that there exists $A_{\delta}\in W_{\delta}$ such that $u_{\delta}$ is the solution of \eqref{e10}. But the fact that $A_{\delta}$ is in $ W_{\delta}$ implies that there exists a subsequence $\{\varepsilon_{m}\}$ of $\varepsilon$ such that $A_{\delta}^{\varepsilon_{m}}$ $H_{e}$-converges to $A_{\delta}$. Hence, the solution $u^{\varepsilon}_{\delta}$ of \begin{equation}\label{e16} \begin{gathered} -\mathop{\rm div}(A^{\varepsilon_{m}}_{\delta}e(u^{\varepsilon_{m}}_{\delta}) )=f^{\varepsilon_{m}}\quad\text{in } \Omega, \\ u^{\varepsilon_{m}}_{\delta}=0\quad\text{on }\partial\Omega \end{gathered} \end{equation} satisfies as $\varepsilon_{m}\to0$ \begin{equation}\label{e17} \begin{gathered} u^{\varepsilon_{m}}_{\delta}\rightharpoonup u_{\delta}\quad\text{weakly in }H^{1}_{0}(\Omega)^{n},\\ A^{\varepsilon_{m}}_{\delta}e(u^{\varepsilon_{m}}_{\delta})\rightharpoonup A_{\delta} e(u_{\delta})\quad\text{weakly in }L^{2}(\Omega)^{n\times n}. \end{gathered} \end{equation} \noindent\textbf{Estimate \eqref{e15}(i):} By Lemma \ref{li6}, (\ref{e17})i) implies that, for every fixed $\delta>0$, \begin{equation}\label{e18} P_{\varepsilon_{m}} ({u^{\varepsilon_{m}}_{\delta}}{|_{\Omega_{\varepsilon_{m}}}}) \rightharpoonup u_{\delta}\quad\text{weakly in }H^{1}_{0}(\Omega)^{n}. \end{equation} Hence, by \eqref{e8}, one has \begin{equation}\label{e19} \lim_{\varepsilon_{m}\to0} \langle f_{\varepsilon_{m}},P^{\varepsilon_{m}}({u^{\varepsilon_{m}}_{\delta}}_ {|_{\Omega_{\varepsilon_{m}}}})-u_{\delta}\rangle=0. \end{equation} From this and \eqref{e13}(i), it comes \begin{equation}\label{e19bis} \lim_{\varepsilon_m\to0} \|P^{\varepsilon_{m}} ({u^{\varepsilon_{m}}_{\delta}}_{|_{\Omega_{\varepsilon_{m}}}}) -P^{\varepsilon_{m}} u^{\varepsilon_{m}} \|_{H^{1}_{0}(\Omega)^{n}} \leq c\delta^{1/2}. \end{equation} But, (\ref{e18}) and (\ref{e3})i) imply \begin{equation*} P_{\varepsilon_{m}}({u^{\varepsilon_{m}}_{\delta}}_{|_{\Omega_{\varepsilon}}}) -P_{\varepsilon_{m}}(u^{\varepsilon_{m}})\rightharpoonup u_{\delta}-u^{0}\quad\text{weakly in }H^{1}_{0}(\Omega)^{n}. \end{equation*} This gives, by using the weak lower semi-continuity of the $H^{1}_{0}$-norm, \begin{equation*} \|u_{\delta}-u^{0} \|_{H^{1}_{0}(\Omega)^{n}} \leq \lim_{\varepsilon_m\to0} \|P^{\varepsilon_{m}} ({u^{\varepsilon_{m}}_{\delta}}_{|_{\Omega_{\varepsilon_{m}}}}) -P^{\varepsilon_{m}}u^{\varepsilon_{m}} \|_{H^{1}_{0}(\Omega)^{n}}, \end{equation*} where $u^{0}$ is the solution of \eqref{e4}. Hence, (\ref{e19bis}) gives \begin{equation*} \|u_{\delta}-u^{0} \|_{H^{1}_{0}(\Omega)^{n}}\leq c\delta^{1/2}. \end{equation*} This is still valid for every $u_{\delta}\in U_{\delta}$, which implies \eqref{e15}(i). \noindent\textbf{Estimate \ref{e15}(ii):} From \eqref{e13}(iii) and (\ref{e19}), it comes $$ \lim_{\varepsilon_m\to0} \|A^{\varepsilon_{m}}_{\delta}e(u^{\varepsilon_{m}}_{\delta}) -A^{{\varepsilon_{m}} }\widetilde{e( u^{{\varepsilon_{m}} }) }\ \|_{H^{1}_{0}(\Omega)^{n\times n}} \leq c\delta^{1/2}. $$ But \eqref{e3}(ii) and \eqref{e17}(ii) imply, as $\varepsilon_{m}\to0$, that $$ (A^{\varepsilon_{m}}_{\delta}e(u^{\varepsilon_{m}}_{\delta})- A^{\varepsilon_{m}}\widetilde{e(u^{\varepsilon_{m}}}))\rightharpoonup (A_{\delta} e(u_{\delta})-A^{0} e(u^{0}))\quad \text{weakly in } L^{2}(\Omega)^{n\times n}. $$ In view of the weak lower semi-continuity of the $L^{2}$-norm, these two last relations give $$ \|(A_{\delta} e(u_{\delta})-A^{0} e(u^{0}))\|_{L^{2}(\Omega)^{n\times n}} \leq c\delta^{1/2}, $$ for every $u_{\delta}\in U_{\delta}$. Hence, $$ \sup_{u_{\delta}\in U_{\delta}} \|(A_{\delta} e(u_{\delta})-A^{0} e(u^{0}))\|_{L^{2}(\Omega)^{n\times n}} \leq c\delta^{1/2}, $$ which, together with Lemma \ref{li7}, gives the claimed result. \end{proof} \section{Main results} \begin{theorem}\label{li10} Let $A_{\delta}\in W_{\delta}$. Then, the solution $u_{\delta}$ of \eqref{e10} satisfies as $\delta\to 0$ \begin{equation}\label{e20} \begin{gathered} u_{\delta}\to u^{0}\quad\text{strongly in } H^{1}_{0}(\Omega)^{n},\\ A_{\delta}e(u_{\delta})\to A^{0} e(u^{0})\quad\text{strongly in } L^{2}(\Omega)^{n\times n}, \end{gathered} \end{equation} where $u^{0}$ is the solution of \eqref{e4}. Moreover, one has the convergence: \begin{equation}\label{e21} \forall p\in[1,\infty[,\quad A_{\delta}\to A^{0}, \end{equation} strongly in $L^{p}(\Omega)$ and weakly $\star$ in $L^{\infty}(\Omega)$. \end{theorem} \begin{theorem} \label{li11} Let $f^{\varepsilon},\;f$ be in $H^{-1}(\Omega)^{n}$ satisfying \eqref{e8}. Suppose that \begin{equation}\label{e22} \forall\varepsilon>0,\;\;\langle f_{\varepsilon},v\rangle=0,\quad \forall v\in H_{0}^{1}(\Omega)^{n},\;v=0\text{ on }\Omega_{\varepsilon}. \end{equation} Then, as $\delta\to0$, \begin{equation}\label{e23} \begin{gathered} u^{\varepsilon}_{\delta}\to u^{\varepsilon}\quad \text{strongly in }H^{1}_{0}(\Omega_{\varepsilon})^{n},\\ A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})\to A^{\varepsilon} \widetilde{e(u^{\varepsilon})}\quad\text{strongly in } L^{2}(\Omega)^{n\times n}, \end{gathered} \end{equation} where $u^{\varepsilon}$ and $u^{\varepsilon}_{\delta}$ are the solutions of \eqref{e2} and \eqref{e9} respectively. \end{theorem} \begin{theorem}\label{li12} Let $f^{\varepsilon},\;f\in H^{-1}(\Omega)^{n}$ satisfying \eqref{e8} and \eqref{e22}. Then, as $(\varepsilon,\delta)\to(0,0)$ \begin{equation}\label{e24} \begin{gathered} u^{\varepsilon}_{\delta}\to u^{0}\quad\text{weakly in } H^{1}_{0}(\Omega)^{n},\\ A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})\to A^{0}e(u^{0})\quad\text{weakly in }L^{2}(\Omega)^{n\times n}, \end{gathered} \end{equation} where $u^{0}$ and $u^{\varepsilon}_{\delta}$ are the solutions of \eqref{e4} and \eqref{e9} respectively. \end{theorem} To prove these results we use similar arguments as those used in \cite{ciodam}. Before giving these proofs, we recall the following lemma: \begin{lemma}[\cite{ciodam}] \label{li3'} Let $\{\psi_{m}\}$ be a sequence of $L^{2}(\Omega)$. Suppose that there exists $\psi,\;\phi\in L^{2}(\Omega)$ such that \begin{gather*} \psi_{m}\to \psi\quad\text{strongly in }L^{2}_{loc}(\Omega),\\ \forall m\in\mathbb{N},\;|\psi_{m}|\leq\phi\quad\text{a.e. in }\Omega. \end{gather*} Then, $\psi_{m}\to \psi$ strongly in $L^{2}(\Omega)$. \end{lemma} \begin{proof}[Proof of Theorem \ref{li10}] Observe first that (\ref{e20}) follows immediately from Proposition \ref{li9}. On the other hand, taking in \eqref{e2} and \eqref{e9}, $f^{\varepsilon}=f\doteq-\mathop{\rm div}(A^{0}e(\varphi\Lambda x))$ with $\varphi\in\mathcal{D}(\Omega)$ and $\Lambda\in\mathbb{R}_{S}^{n\times n}$, then \eqref{e4} reads \begin{gather*} -\mathop{\rm div}\;(A^{0}e( u^{0}) ) =-\mathop{\rm div}(A^{0}e(\varphi\Lambda x))\quad\text{in }\Omega ,\\ u^{0}=0\quad\text{on }\partial \Omega. \end{gather*} This implies, in view of the fact that $A^{0}\in\mathcal{M}_{e}(\frac{\alpha}{C^{2}},\beta,\Omega)$, that $u^{0}=\varphi\Lambda x$. This, together with (\ref{e20}), gives \begin{gather*} u_{\delta}\to \varphi\Lambda x\quad\text{strongly in } H^{1}_{0}(\Omega)^{n},\\ A_{\delta}e(u_{\delta})\to A^{0} e(\varphi\Lambda x)\quad \text{strongly in }L^{2}(\Omega)^{n\times n}. \end{gather*} Taking now $\varphi\in\mathcal{D}(\Omega)$ such that $\varphi=1$ on $\omega$ and where $\omega\subset\subset\Omega$, one obtains \begin{equation}\label{e24bis} \begin{gathered} u_{\delta}\to \Lambda \quad\text{strongly in }H^{1}(\omega)^{n},\\ A_{\delta}e(u_{\delta})\to A^{0} \Lambda\quad\text{strongly in } L^{2}(\omega)^{n\times n}. \end{gathered} \end{equation} On the other hand, one has almost everywhere in $\omega$, \begin{align*} |A_{\delta}\Lambda-A^{0}\Lambda| &\leq |A_{\delta}\Lambda-A_{\delta}e(u_{\delta})|+ |A_{\delta}e(u_{\delta})-A^{0}\Lambda|\\ &\leq \beta|\Lambda-e(u_{\delta})|+ |A_{\delta}e(u_{\delta})-A^{0}\Lambda|. \end{align*} Then, using (\ref{e24bis}), one gets \begin{equation*} A_{\delta}\Lambda\to A^{0} \Lambda \quad\text{strongly in } L^{2}(\omega)^{n\times n}, \end{equation*} for every $\omega\subset\subset\Omega$. Since $|A_{\delta_{m}}\Lambda|\leq\beta|\Lambda|$, this gives by Lemma \ref{li3'} written for $\psi_{m}=A_{\delta_{m}}\Lambda$ (with $\delta_{m}\to0$), \begin{equation*} A_{\delta}\Lambda\to A^{0} \Lambda \quad\text{strongly in } L^{2}(\Omega)^{n\times n}. \end{equation*} By the symmetric properties of $A_{\delta}$ and $A^{0}$, this convergence is still valid for every matrix $\Lambda\in\mathbb{R}^{n\times n}$. Thus \begin{equation*} A_{\delta}\to A^{0} \quad\text{strongly in }L^{2}(\Omega)^{n\times n}. \end{equation*} From this convergence and the fact that $\|A_{\delta}\|_{L^{\infty}(\Omega)}\leq \beta$, one obtains convergence (\ref{e21}). \end{proof} \begin{proof}[Proof of Theorem \ref{li11}] From hypothesis \eqref{e22}, Proposition \ref{li8} and the fact that $P^{\varepsilon}({u^{\varepsilon}_{\delta}}_ {|_{\Omega_{\varepsilon}}})-u^{\varepsilon}_{\delta}=0$ in $\Omega_{\varepsilon}$, it follows that \begin{gather*} \|{u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}-u^{\varepsilon} \|_{H^{1}_{0}(\Omega_{\varepsilon})^{n}}\leq \|P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})-P^{\varepsilon}u^{\varepsilon} \|_{H^{1}_{0}(\Omega)^{n}} \leq c\delta^{1/2},\\ \|A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})-A^{{\varepsilon} }\widetilde{e( u^{{\varepsilon} }) }\ \|_{L^{2}(\Omega)^{n\times n}} \leq c\delta^{1/2}. \end{gather*} Passing to the limit as $\delta\to0$, one obtains (\ref{e23}). \end{proof} \begin{proof}[Proof of Theorem \ref{li12}] \textbf{(i)} Under hypothesis \eqref{e22}, Proposition \ref{li8} gives \begin{equation*} \lim_{(\varepsilon,\delta)\to(0,0)} \|P^{\varepsilon} ({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}) -P^{\varepsilon}u^{\varepsilon} \|_{H^{1}_{0}(\Omega)^{n}}=0 \end{equation*} and the fact that $A^{\varepsilon}\overset{H_{e}}{\rightharpoonup}A^{0}$ implies $$ P_{\varepsilon}u^{\varepsilon}-u^{0}\rightharpoonup0 \quad\text{weakly in } H^{1}_{0}(\Omega). $$ Hence, by passing to the weak limit in $H^{1}_{0}(\Omega)$ as $(\varepsilon,\delta)\to(0,0)$ in the following equality: \begin{equation*} P_{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})-u^{0}= (P_{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})- P_{\varepsilon}u^{\varepsilon})+(P_{\varepsilon}u^{\varepsilon}-u^{0}), \end{equation*} one deduces \begin{equation}\label{e25} P_{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}) \rightharpoonup u^{0} \quad\text{weakly in } H^{1}_{0}(\Omega)^{n}. \end{equation} On the other hand, using \eqref{e22} and Proposition \ref{li8}, one gets \begin{gather*} \|P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}})- P^{\varepsilon}u^{\varepsilon} \|_{H^{1}_{0}(\Omega)^{n}} \leq c\delta^{1/2},\\ \|e(u^{\varepsilon}_{\delta})\|_{L^{2}(T_{\varepsilon})^{n\times n}} \leq c. \end{gather*} This implies \begin{gather*} \|u^{\varepsilon}_{\delta}\|_{H^{1}_{0}(\Omega_{\varepsilon})^{n}}\leq \|P^{\varepsilon}({u^{\varepsilon}_{\delta}}_{|_{\Omega_{\varepsilon}}}) \|_{H^{1}_{0}(\Omega)^{n}}\leq c\delta^{1/2}+ \|P^{\varepsilon}u^{\varepsilon} \|_{H^{1}_{0}(\Omega)^{n}},\\ \|e(u^{\varepsilon}_{\delta})\|_{L^{2}(T_{\varepsilon})^{n\times n}} \leq c. \end{gather*} Since $P^{\varepsilon}u^{\varepsilon}$ is bounded independently of $\varepsilon$ in $H^{1}_{0}(\Omega)^{n}$, one deduces that $u^{\varepsilon}_{\delta}$ is bounded independently of $\varepsilon$ and $\delta$ in $H^{1}_{0}(\Omega)^{n}$. This, together with (\ref{e25}) and Proposition \ref{li6}, gives (\ref{e24})i). \noindent\textbf{(ii)} Using Proposition \ref{li8}, the fact that $A^{\varepsilon}\overset{H_{e}}{\rightharpoonup}A^{0}$ and \begin{equation*} A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})-A^{0}e(u^{0})= (A^{\varepsilon}_{\delta}e(u^{\varepsilon}_{\delta})-A^{\varepsilon} \widetilde{e(u^{\varepsilon})})+ (A^{\varepsilon}\widetilde{e(u^{\varepsilon})}-A^{0}e(u^{0})), \end{equation*} one obtains the convergence \ref{e24}(ii). \end{proof} \subsection*{Acknowledgments} This work was finalized when the author was visiting the Laboratoire Jacques-Louis Lions at the Paris University Pierre et Marie Curie, supported by a grant of the Algerian Ministry for the higher education and scientific research. The author is very thankful for the hospitality during this visit. The author is also grateful to P. Donato for the useful discussions and advice. \begin{thebibliography}{00} \bibitem{ben} A. Bensoussan, J. L. 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