Nonlinear dynamic analysis of a seismically retrofitted reinforced concrete building:
ď‚Ž Reliability analysis The reliable reference value was obtained from 50-recordings set since it is the largest statistical population available. Then reliability index was calculated for average maximum displacement of 30-recordings sets and contrary to expected no average value satisfies EN-1990 prescriptions. On the other hand, reliability index of 7-recordings set could not be determined because no distribution function was properly adjusted with a feasible probability of occurrence. Since for 7-recording sets no function was found to fit, a Displacement Reliability Upgrade Procedure (DRUP) was proposed in order to reach a reliable value as requested by the Eurocode EC0 for the considered case study. It consist in an average increment depending on statistical characteristics of the set. This procedure has managed to achieve a satisfactory displacement at least 90% of the times. Besides only for Magnitude and Radio (Y direction) was observed a high percent of cases where maximum value the searched value taken. Despite of the differences founded on average displacement behavior analysis of 30-recordings, where Magnitude and Radio was denominated as the safest parameter. From reliability analysis the differences among reliable displacements were considerably lower from 30-recordings, which implies that earthquake parameters do not affect significantly 6.2.2
Near Field findings.
As explained in research restrictions near field analysis presented some limitations due to available data. Therefore there is no identification of earthquakes parameters since only one (multi-parameter) search was performed. Regarding to feasible databases definition near field recordings were obtained from Pacific Earthquake Engineering Research (PEER) database From this situation it is noteworthy to state that European near field information needs to be widen since it is generally know that soil conditions and types fault are different so there is an evident lack of knowledge in this field. Finally concerning to records assembling since only 30-recording were found there is no necessity of records classification.
ď‚Ž Evaluation of the average response behavior. Average response behavior of near field presented some divergences among 30-recordings and 7recordings results. Likewise far field results 7-recordings presented a severe fluctuation among their results function distribution could not be found. From this situation, it is inferred that 7 is not a sufficient amount of samples in statistical terms.
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Selection criteria for natural records and reliability analysis of results.