Section C9 – Timber Buildings

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 C9 (download) gives specific recommendations for buildings generically constructed with Timber as well as guidance on establishing capacities for their structural elements and components.

Many existing buildings have elements and components of different construction materials that work together to provide resistance to seismic shaking. The other material sections (C5 to C8) use the same approach to establishing element and component capacities to allow all capacities to be integrated, after making due allowance for deformation compatibility issues.

The recommendations within this section should be used in conjunction with those in Sections C1 to C4 and Part A.

Contact

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 C1, 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 1 MB July 2017
Current Draft 2016_C 1 MB 10 October 2016
Sector Briefing Draft 2016_SB 1 MB 30 June 2016

References

AS1720.1 -2010 Timber Structures Part 1: Design Methods, Australian Standard, Sydney, Australia, 2010

AS/NZS 1170.0:2002. Structural Design Actions – Part 0: General Principles, Australian/New Zealand Standard, 2002.

AS/NZS 1328.1 – 1998 Glued Laminated Structural Timber – Part 1: Performance requirements and minimum production requirements, Australian/New Zealand Standard, 1998

AS/NZS 1328.2 – 1998 Glued laminated structural timber – Part 2: Guidelines for AS/NZS 1328 Part 1 for the selection, production and installation of glued laminated structural timber, Australian/New Zealand Standard, 1998

BRANZ (2013). Study Report SR305 Bracing Ratings for Non-proprietary bracing walls, BRANZ, Wellington, New Zealand. View SR305

BRANZ (2015). Test Report ST1089 Gymnasium Wall Testing for MBIE and MOE, BRANZ, Wellington, New Zealand. View ST1089

Beattie, G. (1999). Earthquake Load Sharing Between Timber Framed and Masonry Walls, Proceedings of the Pacific Timber Engineering Conference, Rotorua, New Zealand, 1999. View Paper

Brunsdon, D., Finnegan, J., Evans, N., Beattie, G., Carradine, D., Sheppard, J. and Lee, B. (2014). Establishing the resilience of timber framed school buildings in New Zealand, Proceedings of the 2014 New Zealand Society for Earthquake Engineering Conference, Auckland, New Zealand, 2014. View Paper 61

Buchanan, A., Carradine, D., Beattie, G. and Morris, H. (2011a). Performance of houses during the Christchurch Earthquake of 22 February 2011, Bulletin of the New Zealand Society for Earthquake Engineering, Vol. 44, No. 4, December 2011. View p. 342-357

Buchanan, A., Carradine, D. and Jordan, J. (2011b). Performance of engineered timber structures in the Canterbury earthquakes, Bulletin of the New Zealand Society for Earthquake Engineering, Vol. 44, No. 4, December 2011. View p. 394-401

Connor-Woodley, P. (2015). Destructive testing of a timber framed “multi” unit to determine realistic seismic assessment parameters, Proceedings of the 2014 New Zealand Society for Earthquake Engineering Conference, Rotorua, New Zealand, 2015. View Paper O29

DBH (2011). Practice Advisory 13: Egress Stairs – Earthquake checks needed for some, Wellington, New Zealand, September 2011. View download page

EN 1995-1-1:2004. Eurocode 5: Design of Timber Structures, European Committee for Standardisation, Brussels, Belgium.

FEMA P-807 (2012). Seismic Evaluation and Retrofit of Multi-Unit Wood-Frame Buildings with Weak First Stories, Applied Technology Council, Redwood City, California, USA. View download page

Giongo, I., Wilson, A., Dizhur, D.Y., Derakhshan, H., Tomasi, R., Griffith, M.C., Quenneville, P. and Ingham, J.M. (2014). Detailed seismic assessment and improvement procedure for vintage flexible timber diaphragms, Bulletin of the New Zealand Society for Earthquake Engineering, Vol. 47, No. 2, June 2014. View p. 97-118 (NZSEE members only)

Ministry of Education (2016). Structural and Geotechnical Guidelines for School Design, Ministry of Education Engineering Strategy Group. View download page

NZS 1170.5:2004. Structural Design Actions, Part 5: Earthquake actions – New Zealand, Standards New Zealand, Wellington, New Zealand.

NZS 3603:1993. Timber Structures Standard, Standards New Zealand, Wellington, New Zealand.

NZS 3604:1978. Code of practice for light timber frame buildings not requiring specific design. Standards New Zealand, Wellington, New Zealand.

NZS 3604:2011. Timber-framed buildings. Standards New Zealand, Wellington, New Zealand.

NZSEE 1996, Assessment and Improvement of the Structural Performance of Buildings in Earthquakes, Incl. Corrigenda 1 & 2, New Zealand Society for Earthquake Engineering, (NZSEE), Wellington, New Zealand. View download page

New Zealand Timber Industry Federation Inc, 2007, Timber Design Guide – Third Edition, 2007.

Opus International Consultants (2015), Canterbury Earthquakes Impact on the Ministry of Education’s School Buildings, Opus, Christchurch, New Zealand. View download page

Pender, M. and Robertson, T., (1987). Edgecumbe Earthquake: Reconnaissance Report, Bulletin of the New Zealand Society for Earthquake Engineering, Wellington Vol.20:3, p. 201-249, September 1987. View p. 201-249 (25 MB PDF)

Quenneville, P. (2009). Design of Bolted Connections: A Comparison of a Proposal and Various Existing Standards, New Zealand Timber Design Journal, Vol. 17, Issue 2, 2009. View p. 3-9

Rainer, J.H. and Karacabeyli, E. (2000). Wood – Frame Construction in Past Earthquakes, Proceedings of the 6th World Conference on Timber Engineering, Whistler, BC, Canada, 2000. View Paper 4.3.2