By default, “hard” contact is directly enforced when using contact pairs in Abaqus/Standard. The dramatic change in contact pressure that occurs when a contact condition changes from “open” (a positive clearance) to “closed” (clearance equal to zero) sometimes makes it difficult to complete contact simulations in Abaqus/Standard; the same is not true for Abaqus/Explicit since iteration is not required for explicit methods. Alternative enforcement methods (e.g., penalty) are available for contact pairs, as discussed in Contact constraint enforcement methods in Abaqus/Standard. Penalty enforcement of the contact constraints is the only option available for general contact. Other sources of information include Common difficulties associated with contact modeling in Abaqus/Standard; Common difficulties associated with contact modeling using contact pairs in Abaqus/Explicit; the “Modeling Contact with Abaqus/Standard” lecture notes; and the “Advanced Topics: Abaqus/Explicit” lecture notes.
