ISSARS: An integrated software environment for structure-specific earthquake ground motion selection

Nonlinear Dynamic Analysis of Masonry Buildings and Definition of Seismic Damage States

“…Instead of, or in addition to, the above, one can also use as a selection criterion the similarity of the response spectra of the recorded motions and a target spectrum, either a code specified one or a site-specific one derived from probabilistic hazard analysis. Currently available software packages like ISSARS [7] use such criteria to select from international databases of recorded motions. As an alternative to this procedure one can use artificial, spectrum-compatible records, whose frequency content might be not very realistic, but the procedure is quicker than the proper selection of recorded motions and (importantly) the number of records needed is substantially less; this convenient option is not allowed when the goals of the analysis include the estimation of the variability in the response quantities.…”

“…Whereas the definition of seismic input (accelerograms) for response history analysis has now become part of practical analysis due to the development of large ground motion databases (in Europe, Japan, and the US) and of appropriate software for record selection [7], the definition of seismic action in nonlinear static analysis is much more of a problem, especially in the common case that the URM building does not have rigid floor diaphragms. Code-type documents [8,9] suggest the use of both a 'uniform' (proportional to the mass distribution) and a first mode based or 'triangular' force pattern, which is a conservative choice as the most unfavourable response quantities among the two patterns are used for the assessment.…”

Assessment of concrete bridges subjected to ground motion with an arbitrary angle of incidence: static and dynamic approach

“…The two prevailing modes define the modal principal axes of Pedini bridge ( Figure 6, system O-M1-M2) and they become identical with the geometric principal axes ( Figure 6, system Oxy), something that is caused by the straight in plan geometry of the selected bridge. At first, the dynamic response of the selected bridge for different angles of incidence of the bidirectional excitation is investigated in comparison to the simpler case of unidirectional excitation for seven ground motions (Table 2), which have been selected according to the following procedure: At first, 30 ground motions with magnitude, M, from 5.8 to 6.8 and epicentral distance, R, from 15km to 40km were selected; 5 of them are records from greek earthquakes and they were extracted from the European Strong Motion Database (Ambraseys et al 2000), while the rest 25 are records from all over the world and they were extracted from the PEER-NGA database (Chiou et al 2008) using the ISSARS software (Katsanos et al 2011). Apart from the (M, R) criterion, the similarity of the response spectra of the records and those of the spectrum used for the design of the bridge (A g = 0.16g, Soil C) was also considered in the selection, while an effort was also made to select records from different earthquakes, to avoid bias in the results.…”

Performance-Based Seismic Design and Assessment of Bridges

“…The critical issue of properly selecting natural accelerograms that are consistent with the design spectrum falls beyond the scope of this chapter; it is only noted that there are currently sound procedures and the associated software, e.g. (Katsanos and Sextos 2013), for selecting 'optimum' sets of seven (or more) accelerograms.…”

“…An additional criterion, not specifically required by Eurocode 8, but important all the same, is the similarity of spectra (those of the selected motions to the target spectrum); software for such multi-criteria selection of the design accelerograms is currently available, e.g. (Katsanos and Sextos 2013).…”