Using Umat Subroutines in Abaqus

[NazBaba]

Hi,

I am very new in UMAT and Abaqus. I want to add this general subroutine example in Abaqus but I don't know how to make it. Please help me..

Coding for Isotropic Isothermal Elasticity
C ----------------------------------------------------------------
C UMAT FOR ISOTROPIC ELASTICITY
C CANNOT BE USED FOR PLANE STRESS
C ----------------------------------------------------------------
C PROPS(1) - E
C PROPS(2) - NU
C ----------------------------------------------------------------
C
IF (NDI.NE.3) THEN
WRITE (7, *) ’THIS UMAT MAY ONLY BE USED FOR ELEMENTS
1 WITH THREE DIRECT STRESS COMPONENTS’
CALL XIT
ENDIF
C
C ELASTIC PROPERTIES
EMOD=PROPS(1)
ENU=PROPS(2)
EBULK3=EMOD/(ONE-TWO*ENU)
EG2=EMOD/(ONE+ENU)
EG=EG2/TWO
EG3=THREE*EG
ELAM=(EBULK3-EG2)/THREE
C
C ELASTIC STIFFNESS
C
DO K1=1, NDI
DO K2=1, NDI
DDSDDE(K2, K1)=ELAM
END DO
DDSDDE(K1, K1)=EG2+ELAM
END DO
DO K1=NDI+1, NTENS
DDSDDE(K1 ,K1)=EG
END DO
C
C CALCULATE STRESS
C
DO K1=1, NTENS
DO K2=1, NTENS
STRESS(K2)=STRESS(K2)+DDSDDE(K2, K1)*DSTRAN(K1)
END DO
END DO
C
RETURN
END