Extended Material Laws

In Radioss, 99 material user laws can be defined for 3D and 2D solid elements, connection element, and 3D shell elements.

User laws for beam or truss elements are not yet available.

To define a user law, two subroutines for each law must be provided. One must be linked with Radioss Starter and the other with Radioss Engine.
  • The Starter subroutine is called LECMUSERnn (where nn = 01, 02, 03, … 99) and reads material data and initializes material parameters
  • The Engine subroutine for solids is called LUSERnn (where nn = 01, 02, 03, … 99) and computes the solid element stress tensor at the integration point. The corresponding shell subroutine is called LUSERnnC (where nn = 01, 02, 03, … 99)
Note: All communication between Radioss and the User’s subroutines takes place within the argument list.