At the hinge location define a set of coincident nodes, one node connected to one of the beams, the other node connected to the other beam. Connect a rigid element (MPC) between the coincident nodes in 5 degrees of freedom that will constrain all translational degrees of freedom plus 2 rotational degrees of freedom, allowing for one rotational degree of freedom between the two nodes. The unconstrained degree of freedom defines the hinge.
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