C DECHAT    SOURCE    CHAT      05/01/12    22:39:01     5004           
C DECHAT     SOURCE    INSL       24/10/96    
      SUBROUTINE DECHAT(EPSRX,STRNX,STRNRX,SIGMRX,TANG,S1X,EDT,EDC,
     1 EPST,DEFR,IFISU,IPLA,EQSTR,RTM,EPSC,IREFE,EX,RB,ALPHA,EPSU,
     2 EPO1,ICAL,IBB1,IGAU1,IDIR,PASDT)
C
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)
      CHARACTER*8 PASDT
C
C       CE SOUS-PROGRAMME GERE LA REFERMETURE DES FISSURES.
C       CALCUL DE LA NOUVELLE PENTE EDT (RESTAURATION PROGRESSIVE
C         DE LA RAIDEUR DE LA FISSURE
C
      IREFE=0
      RBT=ALPHA*RB
      REFERM=3.D0*EPSU
      IF(DABS(EDC).LT.0.1D-06) EDC=0.D0
      IF(EDC.NE.0.D0) REFERM=REFERM+DEFR
      IF(STRNRX.GT.EPSRX) RETURN
      IF(STRNRX.GT.REFERM) THEN
        IREFE=1
        S1X=0.D0
        RETURN
      ENDIF
      IFISU=0
      IF(EDC.NE.0.D0) EPST=DEFR-RBT/EDC
C
C       REFERMETURE POUR UN POINT INITIALLEMENT TENDU
C
C       CALCUL DU MODULE EDT LORS DE LA REFERMETURE
C
C     
       IF(STRNRX.GT.EPST) THEN
        IF(EPSRX.LE.REFERM)THEN
         EDT=(RBT+RTM)/(EPSRX-EPST)
         IF(IPLA.EQ.2.AND.EQSTR.LT.RBT) EDT=EQSTR/(EPSRX-EPST)
         S1X=EDT*STRNX+RTM
        ELSE
         EDT=RBT/(REFERM-EPST)
         IF(IPLA.EQ.2.AND.EQSTR.LT.RBT) EDT=EQSTR/(REFERM-EPST)
         S1X=EDT*(STRNRX-REFERM)
        ENDIF
        TANG=EDT
       ELSE
        IF(STRNRX.LT.EPSC) THEN
         EPEQ=DABS(STRNRX)
         CALL CDCY(EPEQ,SEQ,IPLA,TANG,EX,RB,EMAX,EPO1,ICAL)
C
C       ACTUALISATION DE EQSTR
C
         EQSTR=SEQ
         S1X=-SEQ
        ELSE
C
C ON EST SUR LA PENTE EDC
C
         S1X=EDC*(STRNRX-DEFR)
         TANG=EDC
        ENDIF
       ENDIF
       IF(EDT.LT.0.D0) THEN
         WRITE(*,*) ' !!!!  ATTENTION DANS DECHART EDT < 0 APPELE PAR'
     &  ,PASDT  
           WRITE(*,94) IBB1,IGAU1,IDIR
 94        FORMAT(' ELEME=',I3,'POINT=',I2,' IDIR=',I2)
           WRITE(*,*)'RTM=',RTM,'RBT=',RBT,'IPLA=',IPLA,'IFISU=',IFISU
           WRITE(*,*) 'EPSRX= ',EPSRX,' SIGMRX= ',SIGMRX
           WRITE(*,*) 'STRNRX= ',STRNRX,' EPSC= ',EPSC
           WRITE(*,*) 'EQSTR= ',EQSTR,' EPST= ',EPST,' DEFR=',DEFR
           WRITE(*,*) 'ERREUR EDT<0 ! EDT=',EDT,' EDC=',EDC
           STOP
          ENDIF
      RETURN
      END