Section C3 – Earthquake Loading

The Seismic Assessment of Existing Buildings (the Guidelines) provides a technical basis for engineers to carry out seismic assessments of existing buildings within New Zealand.

Part C of the Guidelines describes the Detailed Seismic Assessment (DSA) process used to assess the seismic behaviour of a building. This is a more comprehensive assessment than the Initial Seismic Assessment process described in Part B. The DSA assesses the structural load paths within the building, the capacity of each structural element, the likely inelastic mechanisms, the global building response to earthquake shaking and the impact of secondary structural and critical non-structural building elements.

The DSA process is based on the Part A principles, which are an integral part of the seismic assessment process. Sections C1, C2, C3 and C4 provide an overview of the DSA process, the assessment procedures and analysis techniques, the earthquake demands and geotechnical considerations. Sections C5 to C9 provide recommendations for specific materials and Section C10 provides recommendations for secondary structural and non-structural elements. Each of these build on the common aspects within Sections C1 to C4 and Part A.

Summary and Download

Section C3 (download) explains how to determine the earthquake hazard and loading requirements used to assess the ULS demand that relates the building capacity to the standard required for a new building.

This section relates the guideline to the appropriate version of the New Zealand structural design actions standard NZS 1170.5:2004 depending on the purpose of the assessment and provides guidance on the derivation of spectral displacement demand and the acceleration displacement response spectra (ADRS). It also covers the determination of earthquake demand (e.g. peak ground acceleration, number of cycles, representative (effective) magnitude for geotechnical considerations.


This web site has a searchable Knowledge Base with answers to questions about the Guidelines. Use article links in the Knowledge Base section to the right to view these.

If you have a question about Section C3, please check the Knowledge Base articles for Part C. If it is not addressed there, please refer to Writing Questions so your question can be efficiently addressed when you send it using the form below. Use the article links in the Knowledge Base section to the right for questions on Part A or Part B.

Version Control

Download Link Version Size Issued
Initial release (Current) 1 2 MB July 2017
Consultation Draft 2016_C 2 MB 10 October 2016
Sector Briefing Draft 2016_SB 1 MB 30 June 2016