A Database for Assisted Assessment of Torsional Response of In-Plan Irregular Buildings

Nonlinear static analysis is currently the most popular method of analysis for the prediction of the seismic response of buildings. However, when dealing with in-plan irregular buildings, the nonlinear static analysis does not allow a proper assessment of the torsional response. In particular, the torsional response modifies the displacement demand of the two sides of the deck with respect to that of the corresponding torsionally balanced system: the displacement demand of the flexible side increases, while that of the stiff side decreases or increases depending on the features of the building. In this paper, the ratio of the maximum displacements of the asymmetric system to the maximum displacement of the corresponding planar system is determined for a large set of single storey systems. The results of this investigation are used to populate a database for the assisted assessment of buildings. This database can be interrogated by means of parameters characterizing the building to be assessed and provides the user with the amplification/deamplification of displacement demand of the two sides of the building with respect to that of the corresponding planar system. The database is conceived in such a way to include new cases without modifying its structure. This allows the database to be easily expanded when new parameters will be explored and new results will be available.