NMIT Arts & Media Building – damage mitigation using post-tensioned timber walls

The success of the NMIT Arts & Media project hasproven that with innovative design multi-storey timberconstruction is a viable option and can compete withtraditional steel and concrete construction. Theengineered structural system has been evaluated asbeing very cost competitive, and it is believed that it willbe attractive for use in future commercial buildingdevelopments.The NMIT building project offered a unique opportunityfor Aurecon structural designers. The first commercialuse of the Pres-Lam post-tensioned rocking-dissipativetimber system marks a fundamental change in timberdesign. The Performance-Based Engineering philosophyensures that the building will continue to function afterthe design level seismic event. In the wake of the recentCanterbury Earthquakes this project demonstrates tobuilding owners that a fully functioning building post-earthquake can be achieved in a cost effective manner.To date few commercial multi-storey timber buildings inNew Zealand have been designed or built that wouldcompete with a similar concrete or steel building. This isnot necessarily due to lack of capability of timberproducts, but rather through lack of opportunity andindustry misconceptions. The latest trends in buildingdesign, especially in the European Union, are seeing arapid growth in multi-storey timber buildings. This isprimarily for reasons of sustainability, where timber isused as a carbon sink but more recently because ofimproving design techniques and knowledge. Timber isnow promoted for affordability and speed ofconstruction.