The tests exercise the three ways in which the *CONTACT INTERFERENCE option can be used. Either a simple amount of allowable interference is specified, an allowable interference along a prescribed direction is specified, or the automatic shrink fit procedure is invoked. In this latter case ABAQUS initializes the amount of allowable interference at each contact point with the penetration it calculates at the beginning of the analysis.

Most of the models consist of two elements lying next to each other with their contact surfaces initially interfering by an amount of 0.2. In the case of rigid surfaces there is only one element initially interfering with a straight rigid surface. The solid elements are either 4-node quads or 8-node bricks, as a substrate for the appropriate contact elements. The *CONTACT INTERFERENCE option with an amount of 0.2 is used to resolve the interference in (typically) five increments.

In the case of tube within tube elements (ITT) the model consists of two beams at a variable transverse distance from each other. One is totally fixed, and the other is fixed only axially. An initial tube clearance of 0.5 produces interferences of up to 0.5. The *CONTACT INTERFERENCE option with a magnitude of 0.5 is used to resolve the interference.