*MAT_138 (COHESIVE_MIXED_MODE)

LS-DYNA Input Interface KeywordThis model expresses a constitutive relation of ductile adhesive materials in 2 modes for normal and tangential directions.

Format

(1) (2) (3) (4) (5) (6) (7) (8)
*MAT_138 or *MAT_COHESIVE_MIXED_MODE
mat_ID ρ i ROFLG Idel EN ET GIC GIIC
XMU TN TT UDN UTD Gamma    

Definition

Field Contents SI Unit Example
mat_ID Material identifier.

(Integer)

  
ρ i Initial density.

(Real)

 [ kg m 3 ]
ROFLG Mass calculation flag.
= 0 (Default)
Element mass is calculated using density and volume.
= 1
Element mass is calculated using density and mean area.

(Integer)

  
Idel Failure flag indicating the number of integration points to delete the element (between 1 and 4).

Default = 1 (Integer)

  
EN Stiffness normal to the plane of the cohesive element.

(Real)

 [ Pa ]
ET Stiffness into the plane of the cohesive element.

(Real)

 [ Pa ]
GIC Energy release rate for mode I.

(Real)

 [ Pa.m ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaaca WGqbGaamyyaiaac6cacaWGTbaacaGLBbGaayzxaaaaaa@3B48@
GIIC Energy release rate for mode II.

(Real)

 [ P a . m ] MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaamWaaeaaca WGqbGaamyyaiaac6cacaWGTbaacaGLBbGaayzxaaaaaa@3B48@
XMU Exponent of the mixed mode criteria.

(Real)

  
TN Peak traction in normal direction.
< 0
Function ID (abs(T)) of peak traction value as a function of the square root of the area of ​​the median plane of the connecting element.
= 0
Peak traction computed from UDN and GIC.
> 0
Peak traction value.

(Real)

 [ Pa ]
TT Peak traction in tangential direction.
< 0
Function ID (abs(S)) of peak traction value as a function of the square root of the area of ​​the median plane of the connecting element.
= 0
Peak traction computed from UTN and GIIC.
> 0
Peak traction value.

(Real)

 [ Pa ]
UDN Ultimate displacement in the normal direction.

Used only if TN=0, then T N = 2 * G I C U D N MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamivaiaad6 eacqGH9aqpdaWcaaqaaiaaikdacaGGQaGaam4raiaadMeacaWGdbaa baGaamyvaiaadseacaWGobaaaaaa@3EFB@

(Real)

 [ m ]
UTD Ultimate displacement in the tangential direction.

Used only if TT=0, then T T = 2 * G I I C U T N MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamivaiaads facqGH9aqpdaWcaaqaaiaaikdacaGGQaGaam4raiaadMeacaWGjbGa am4qaaqaaiaadwfacaWGubGaamOtaaaaaaa@3FDF@

(Real)

 [ m ]
Gamma Benzeggagh-Kenane exponent for the mixed mode.

(Real)

  

Comments

  1. This keyword maps to /MAT/LAW117.
  2. The option “_TITLE” can be added to the end of this keyword. When “_TITLE” is included, an extra 80 characters long line is added after the keyword input line which allows an entity title to be defined.