Stiffener cross sections may be built-up from subelements described either by explicit geometry or by geometric properties. Smeared stiffeners are also an option. Shell elements include a linear triangle, linear and quadratic quadrilaterals, and transition elements for mesh refinement. A Timoshenko beam is available for modeling shell stiffeners. Rigid links may be used to connect the spring, thereby providing rotational as well as translational stiffness.
Thermal loading is defined by arbitrary definition of temperature throughout the structure.
MPC may be linear or nonlinear, while Lagrange constraints are linear constraint equations. For transient analysis, initial displacements and velocities may be defined. For example, user-written subroutines can define arbitrary functional relationships, such as spatial variation of constitutive properties in a wall fabrication, or temporal variation of loading for transient analysis. In fact, nearly all aspects of model definition, from the most basic operations to extremely complex ones, can be performed via user-written subroutines. We return value to the Software community in the form of services and original software.