This paper offers the first results of a new research study on earthquake-induced pounding between adjacent buildings, and its mitigation. In the first part of the paper the two main strategies adopted for the analysis of kinematic as well as dynamic contact of structural systems, that is, the stereomechanical and the contact force-based approaches, are presented. Attention is then devoted to the variational techniques by which the two approaches are formulated within finite element solutions, represented by the Lagrange multiplier and the penalty methods, respectively. Starting from this theoretical recognition, in the second part of the work the penalty method is implemented in the computational model devised for the dynamic non-linear analysis of pounding between real structures. This model is applied to an actual case study, given by a two-story and a five-story R/C adjacent buildings, for which a mitigation solution based on the installation of fluid-viscous dissipaters across the existing inadequate separation joint, is also proposed.
