Rotational response of RC structures imposed by seismic pounding with adjoining structures

Structures that are partly in contact experience considerable torsional vibrations during earthquakes. This phenomenon is referred to in the literature as asymmetric pounding. The present paper deals with the effects of asymmetric pounding on the rotational seismic response of reinforced concrete buildings. In particular, the study aims to identify the influence of several parameters that have never been addressed in the past, such as the masonry infills distribution, the buildings' structural system and the seismic excitation directionality. Moreover, the effects of asymmetric pounding on the overall building response are evaluated through the calculation of representative response quantities. Based on the mean storey drifts, an approximate estimation of the earthquake economic losses due to asymmetric pounding is also attempted. For this purpose, two 8-storey reinforced concrete frame buildings which are sequentially considered in partial contact with an adjacent 6-, 3- or single-storey structure, are analyzed for three natural seismic excitations. Crucial aspects of the topic are highlighted: the unfavorable pilotis effect, the importance of ground motion directionality and the economic implications of the phenomenon.