ABSTRACT
The application of EC8 criteria to classify the regularity of buildings in plan will enforce the use of spatial multimodal analyses for the vast majority of buildings. Since this a situation with practical and economic disadvantages, the study of the need for such restrictions is justified. In the authors opinion, the main criteria to allow the use of simplified methods of analysis to evaluate seismic effects in buildings must be the accuracy which it is possible to attain with those methods (as compared with the standard spatial multimodal analyses) without reducing the safety level. In this paper results of parametric studies which point to the possibility of extending the range of applicability of simplified analyses of buildings are presented.
