MCOHED

Bulk Data Entry Defines the material properties for cohesive materials.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MCOHED MID KX KY KZ SFC VED   MXDMG  
  DMGINIID DMGEVOID              

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MCOHED 2 9000. 3000. 3000. -1.0 1.0e-3   0.99  
  20 23              

Definitions

Field Contents SI Unit Example
MID Material identification number.

No default (Integer > 0)

  
KX, KY, KZ Penalty stiffness in X, Y and Z directions in the material coordinate system.
KZ
The normal direction.
KX and KY
The two tangential directions.

No default (Real)

  
SFC Stiffening factor in compression.
Positive value (Real > 0.0)
Directly prescribed stiffness
Negative value (Real < 0.0)
Defines a stiffness scaling factor. The stiffness scaling factor is equal to |Real< 0.0|. The scaling is applied to the initial stiffness in separation condition.
SOFT
Takes the maximum diagonal value in the global stiffness of the numerical model multiplied by 1.0E2 as the compression stiffness.
HARD
Takes the maximum diagonal value in the global stiffness of the numerical model multiplied by 1.0E6 as the compression stiffness.
AUTO
Takes the maximum diagonal value in the global stiffness of the numerical model multiplied by 1.0E4 as the compression stiffness.

Default = 1.0

  
VED Factor for viscous energy dissipation.

Default = 0.0 (Real > 0.0)

  
MXDMG Maximum damage index, above which the cohesive element is excluded from analysis.

Default = 1.0 (Real ≥ 0.0)

  
DMGINIID Damage initiation card ID.

No default (Integer > 0)

  
DMGEVOID Damage evolution card ID.

No default (Integer > 0)

  

Comments

  1. The material identification number should be unique for all MAT1, MAT2, MAT3, MAT8, MAT9, MGASK, MCOHE, MCOHED entries.
  2. In some cases, snap-back phenomena could appear in numerical models with cohesive elements. VED can be used to stabilize the solution.