Implications for Design of Parts and Components from Updates to New Zealand Seismic Loading Standard and National Seismic Hazard Model

Abstract

New Zealand engineering practitioners will see revisions to the seismic loading standards for non-structural elements (parts and components) in the draft technical specification TS1170.5. This paper considers the implications for the horizontal design force on parts and components by applying the approach to case study structures of different heights in Christchurch and Wellington. Comparisons are made between new seismic loading standards approach with the new national seismic hazard model and (i) the approach in the previous standard, NZS1170.5:2004 A1 2016, with the new seismic hazard model, showing the influence of the change in parts approach; and (ii) the previous approach with the previous hazard, showing the overall change loadings for design practice. The results suggest that demands on parts that could be resonant with the building period and that are characterised by low ductility capacity would be expected to require larger design strengths. However, for most parts, the results indicate that substantial reductions in design strength requirements may be achieved using the updated approach, particularly for parts and components that are rigid, develop nonlinear response, or are mounted over the lower levels of the structure.