Current seismic design philosophy used worldwide tolerates a degree of damage at locations predefined by the designer, as long as a complete structural collapse is precluded. By accepting plastic deformations, the maximum acceptable forces can be controlled and construction costs can be reduced. Major earthquakes, e.g. the Canterbury earthquakes, showed that well-designed structures behave as anticipated. The joints suffered plastic deformation as the designer intended, while the occupants remained alive. Repair costs, however, were often high. Costs also accrue because, post-earthquake, the infrastructure is no longer fit for purpose. These costs are very difficult to predict.
Low-damage seismic design, in contrast, can be achieved by activating rigid-like body movement of structural members. Development of forces resulting from structural local deformation can then be prevented. Consequently, associated damage to structural members can be avoided. Recent research outcomes at the University of Auckland Centre for Earthquake Engineering Research will be presented.
