Use the Additional Creep subnode to define additional contributions to the creep model defined by the parent Creep node, such as primary or tertiary creep behavior. A Creep node can have any number of Additional Creep subnodes with different settings to model advanced creep mechanisms. Note that the time-integrated creep strain εcr is computed for the sum of all creep rate contributions only; the same applies for the equivalent creep strain εce.

The Nonlinear Structural Materials Module or the Geomechanics Module are required for this feature, and the available options depend on the used products. For details, see https://www.comsol.com/products/specifications/.

The available settings in this section are the same as for the Creep node. The Equivalent stress setting has an additional option — From parent, which is default. When selected, the Additional Creep subnode will use the same equivalent stress σe as in the parent Creep node.

Physics tab with Creep node selected in the model tree: