President’s Report 2016 #1

The Australian Earthquake Engineering Society, in conjunction with the Zealand Society for Earthquake Engineering, hosted the 10th Pacific Conference on Earthquake Engineering at the Menzies Hotel in Sydney on November 6-8, 2015. The participants included earthquake scientists and engineers from around the entire Pacific Rim. Each morning the Conference began with a Keynote talk followed by invited talks by internationally recognised experts in earthquake science and enginering.

This conference was motivated by the knowledge that the Pacific region contains nearly all of the world’s subduction zones and is subject to the world’s largest and most frequent earthquakes. Although remarkable improvements in our understanding of earthquake effects and their impact on the built environment continue to be made throughout the Pacific region, recent events in Chile, Japan and New Zealand have reminded us again of the severity of earthquake hazards and of the need to redouble our efforts to understand them and learn how to mitigate their effects.

Long experience has taught us that from both humanitarian and economic viewpoints, pre-emptive risk mitigation through the development and implementation of seismic hazard maps and seismic building codes is far less costly than disaster response and recovery. The conference theme, ‘Building an Earthquake-Resilient Pacific,’ encouraged participants to meet the requirements of a truly resilient Pacific society that incorporates the social, economic and human dimensions of earthquake engineering.

The public in Australia are generally unaware that a magnitude 6.2 earthquake, the size of the destructive Christchurch earthquake of 2011, occurs in Australia on average once every 10 years or so. The impact of such an earthquake on any one of our cities, a rare but forseeable scenario, would be devastating given that few modern buildings in Australia are designed to adequately resist the ground motion arising from these large but rare events. Old buildings are most at risk. Whilst earthquakes occur infrequently, the risk as assessed by the insurance industry is high, given the high density and vulnerability of our buildings.

This is the motivation for our Improving Robustness of Buildings Initiative, which is the key focus of AEES in 2016 and led by our Vice President, Peter McBean. The aim of this initiative is to foster an understanding among practicing structural engineers of the fundamental principles that underlie the standards and codes that are used in routine practice. We believe that an understanding of these principles can play an important role in enhancing the robustness of structures that are designed following the code provisions, without necessarily increasing their costs. We also aim to foster consideration of performance based design concepts, in which the life safety goal of current code-based design ground motion levels is supplemented by considering structural stability at higher ground motion (lower probability) levels.

The Christchurch earthquakes of 2010-2011 demonstrated many conditions that could lead to adverse structural behaviour in Australia. Many people were killed by falling masonry, especially parapet walls. Many were also killed in poorly designed concrete frame buidings. We should encourage governments and city councils to take measures to mitigate these well known risks. They should also foster an enviroment in which new construction follows design procedures and construction practices that provide robustness and resilience to withstand earthquakes. The minimal costs of doing so are dwarfed by the massive economic losses and loss of life that could otherwise occur in Australian cities.

City councils will be at the forefront of response and recovery following the next earthquake, as was the city council in Newcastle NSW after the destructive earthquake there 25 years ago. We should encourage council engineers to prepare by identifying and fostering the repair of hazardous buildings, especially schools and hospitals; establishing good communication links with seismological agencies through EMA; compiling a list of trained Urban Search and Rescue (USAR) engineers in their area; and making plans for earthquake response and recovery.

Paul Somerville, President, AEES