Seismic Zonation and Default Suite of Ground-Motion Records for Time-History Analysis in the North Island of New Zealand

Abstract

A seismic zonation to be used in the selection of ground-motion records for time-history analysis of buildings in the North Island of New Zealand is presented. Both deaggregations of the probabilistic seismic hazard model and the seismological characteristics of the expected ground motions at different locations were considered in order to define the zonation. A profile of the records expected to apply within each zone according to the identified hazard scenarios is presented and suites of records are proposed for each zone, based on region-wide criteria, to be used in time-history analysis in the absence of site specific studies. A solution for structures with fundamental periods of between 0.4 and 2.0 seconds is proposed, considering a 500-year return period and two common site classes (C and D, according to the New Zealand Loadings Standard).

Seismic assessment of out-of-plane loaded unreinforced masonry walls in multi-storey buildings

“…Based on consultation with Oyarzo-Vera et al 2011, an ongoing study to identify appropraite suites of records for South Island, New Zealand, suggests that no ground motion record with near-fault characteristics is included in the potential earthquake records recommended for the South Island. The ongoing study further suggests that the majority of the records used to represent seismicity of the South Island are the same as those presented for Zone B and C in Oyarzo-Vera et al (2011).…”

“…A suite of records were used for 5 different regions of New Zealand -North Island (Fig. 8.3) as recommended by Oyarzo-Vera et al (2011), and collectively the 30 earthquakes listed in Tables I.1 and I.2 of Appendix I were utilised in the performed analyses. The average %NBS was then calculated using the methodology discussed in Section 8.3.…”

“…As the study by Oyarzo-Vera et al (2011) considered records that were suitable for New Zealand seismicity, the generated results of the parametric study cannot be readily used for regions having different seismological signature, e.g. Australia that involves ground motions producing substantially lower spectral displacements than that obtained for New Zealand.…”

“…The displacement spectra for unscaled records are provided in this section. It should be noted that all the suites of 7 records have been subsequently scaled, with the scalng factors obtained from Oyarzo-Vera et al (2011). The scaling procedure resulted in the average acceleration spectra of each suites of 7 records to match the design acceleration spectra suggested by the NZS (2004).…”

Proposed Simplified Approach for the Seismic Analysis of Multi-Storey Moment Resisting Framed Buildings Incorporating Friction Sliders

“…To select an appropriate past earthquake time-history record, the method established in [20] was implemented. This resulted in the El Centro 1940 earthquake record being an appropriate record to apply to the model.…”