11.2.2 Total Stress ELSGUS

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11.2.2 Total Stress `ELSGUS`

User-supplied subroutine ELSGUS calculates the total stresses $\boldsymbol\sigma$ _n from the total strains $\boldsymbol\varepsilon$ _n in nonlinear elasticity.

(Fortran)

      SUBROUTINE ELSGUS( eps, ns, sig )

$\begin{figure}\centering \begin{tabbing} out~~\=\textsc{dbl}~~\=\texttt{abcdef... ...bl}\>\texttt{sig(ns)}\>Total stress vector. \\ [-3ex] \end{tabbing} \end{figure}$

eps: is the total strain vector $\boldsymbol\varepsilon$ _n , for various stress/strain states [Table 11.1].
ns: is the length n of the stress/strain vectors, indicates the stress/strain state.
sig: is the output total stress vector $\boldsymbol\sigma$ _n , for various stress/strain states [Table 11.1].

Getting data (Fortran)

      CALL GTC( '../MATERI/YOUNG', young, 1 )
      CALL GTC( '../MATERI/POISON', pois, 1 )

$\begin{figure}\centering \begin{tabbing} out~~\=\textsc{dbl}~~\=\texttt{abcdef... ...extsc{dbl}\>\texttt{pois}\>Poisson's ratio. \\ [-3ex] \end{tabbing} \end{figure}$

young: is the linear elastic Young's modulus E .
pois: is the linear elastic Poisson's ratio $\nu$ .

(file.f)

      SUBROUTINE ELSGUS( EPS, NS, TSIG )
C
      INTEGER          NS
      DOUBLE PRECISION EPS(NS), TSIG(NS)
      DOUBLE PRECISION YOUNG
C
C...     Get Young's modulus
      CALL GTC( '../MATERI/YOUNG', YOUNG, 1 )
C
C...     Calculate {TSIG} for plane stress
      IF ( NS .EQ. 4 ) THEN
         TSIG(1) = YOUNG*EPS(1) + 1000.D0*YOUNG*EPS(1)**2
         TSIG(2) = YOUNG*EPS(2) + 1000.D0*YOUNG*EPS(2)**2
         TSIG(3) = YOUNG*EPS(3) + 1000.D0*YOUNG*EPS(3)**2
         TSIG(4) = 0.5D0*YOUNG*EPS(4)
      END IF
C
      END

DIANA-9.3 User's Manual - Material Library
First ed.

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