VISCO

Bulk Data Entry Defines parameters for nonlinear analysis involving time-dependent material behavior.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
VISCO ID CETOL TINT            

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
VISCO 2                

Definitions

Field Contents SI Unit Example
ID Each VISCO Bulk Data card must have a unique ID.

No default (Integer > 0)

 
CETOL Tolerance for viscoelastic time integration. Ensures that the viscoelastic/creep strain increment is controlled by the specified tolerance.

If not specified or zero, fixed time integration will be used.

No default (Real ≥ 0)

 
TINT Numerical time integration scheme for solving creep equations. 3
IMPL (Default)
Implicit/backward Euler method
XPL
Explicit/forward Euler method
 

Comments

  1. The VISCO Bulk Data entry can be referenced in the subcase section to specify if viscoelasticity/creep analysis is activated in that subcase.
  2. CETOL is the tolerance to control the time increment size. It ensures the viscoelastic/creep strain increment is controlled by the specified tolerance.
  3. Creep problems are often solved efficiently by the explicit integration method. This is computationally efficient because, unlike implicit methods, iterations are not required. However, the explicit method is conditionally stable, due to the maximum time step size limitations.