Accelerogrammi Naturali Compatibili con le Specifiche dell'OPCM 3274 per L'analisi Non Lineare delle Strutture

Among all possible options, natural recordings are emerging as the more attractive input for non-linear dynamic analysis of structures since accessible waveform databases are available and some evidences show that only a limited number of criteria have to be considered in selection to get unbiased estimation of seismic demand. The OPCM 3431, the recently released Italian seismic code, allows the use of real ground motions for the nonlinear seismic analysis of structures. The main constraint to be satisfied by the chosen record set is the matching, of the average spectral ordinates, with the elastic code spectrum. In fact, the latter may not be underestimated more than by 10% in a broad range of periods. Code’s spectral shape depends on the seismicity of the site, and on the soil conditions. The study presented in the paper investigated the European Strong Motion Database to establish whether combinations of records complying with the OPCM 3431 prescriptions, and also accounting for additive constraints believed to matter in the non-linear assessment of buildings, may be found. Results refer to soft soils, stiff soils and rock. The accelerogram sets obtained tend to not overestimate the code’s spectrum; to have the minimum record-to-record variability; and are not manipulated (i.e. not scaled), to avoid “epsilon” related issues. Details about such results and sets to download can be found at http://www.reluis.unina.it.