Eurocode 8: Use of advantageous formulations for improved and safe design

The purpose of the paper is to share the experience in application of Eurocode 8. Following the existing framework of the European standard two engineering development of two specific topics are proposed. First deals with modelling the seismic action aiming to take into account spatial variability of the seismic action. It is proven that the inclusion of rotational components may influence the action effects and the results provide unsafe design. Evaluation is carried out through response spectrum method. The second topic studies the use of performance based seismic design as a tool to prove the need for seismic strengthening and verification of the benefit. Both target and actual capacity spectra are compared to make assessment of the lateral resistance of existing and strengthened structure. Insufficient elastic stiffness and insufficient yield strength are considered as the most typical situations frequently met in the design practice and which can be settled by seismic strengthening. Discussions and conclusions concerning the philosophy of the assessment procedure are presented.