Resilience is the buzzword for many earthquake engineers.More specifically it’s building resilience and equipping communities to become disaster resilient in the face of earthquakes and other extreme events.
In collaboration with the University of Canterbury’s (UC) Quake Centre, Professor Michel Bruneau (Structural Engineer, University of California, Berkeley, USA), has spent six weeks in Christchurch researching and analysing building damage in the CBD following the Canterbury earthquake sequence of 2010-2011.
During a recent lecture at UC, Professor Bruneau noted that “the first time I heard the word ‘resilience’ was in 2002 at MCEER (The Multidisciplinary Center for Earthquake Engineering Research).”
“Now more than a decade later, and ‘resilience’ is everywhere…google it and you’ll find ‘resilient cities’ in Tokyo, New York and San Francisco. There’s the Rockefeller Foundation list of 100 Resilient Cities, with post earthquake Christchurch featuring as one of these.”
“The EERI (Earthquake Engineering Research Institute) distinguished lecture in 2013 was about resilience and the 16WCEE (World Conference in Earthquake Engineering) in Santiago, Chile in 2017, had the byline: Resilience, the new challenge in Earthquake engineering.”
Professor Bruneau jokes, “Pretty soon we may have a city that calls itself ‘Resilience’ because the word is becoming so popular!”
Humour aside though, another challenge lies in actually defining resilience, or - more specifically for earthquake engineers - quantifying resilience.
Resilience is defined in the Cambridge dictionary as, ‘the quality of being able to return quickly to a previous good condition after problems.’ It’s also defined as something that, ‘has the ability to recover quickly and readily from illness, change, depression, adversity or misfortune and to become healthy, happy or strong again.’
“When it comes to earthquake engineering though,” says Professor Bruneau, “we need to be a lot more rigorous about what we call ‘resilience’ because it impacts so hugely on our communities and we need to define the fundamental essence of ‘resilience’ according to what it means for our work.”
“The concept of earthquake resilience is to identify the challenges, risks (and opportunities), facing today’s cities. While each city has a unique risk profile, there are also a number of common threats, stressors and shocks that hinder all cities. And while it is important for cities to focus on life-saving resilience in a disaster or a major event, what we are ultimately trying to do as engineers is build economic resilience too.”
So what does this mean for the earthquake engineer? What is the role of the earthquake engineer?
The obvious role is to create earthquake resilient infrastructure, to minimise loss of functionality and achieve fast recovery at minimum cost. But there are numerous structural engineering dilemmas to consider here.
There is a large stock of buildings globally not yet at earthquake code standard. Many current owners of these buildings do not want resilience or don’t know why they should immediately need it, often due to the cost involved. Due to this resistance, achieving community resilience ‘one building at a time’ may end up taking a very long time. And on it’s own, one resilient building may be pointless, unless the entire neighbouring community of buildings are collectively built to code and equally resistant.
“Resilient buildings are good, but community and economic resilience throughout something as significant as a major earthquake, requires more than just resilient buildings,” says Professor Bruneau.
So where does this leave a possible solution?
“It’s really hard to think of an overall immediate solution,” says Professor Bruneau. “Sometimes as engineers, we will throw any crazy idea in there - it’s still a valuable starting point, stirs up discussion and may just lead us to something viable and workable.”
“One ‘crazy’ concept we had was: The lifeline (resilient) building district.”
This would be an ‘island’ (figuratively speaking) of buildings within a city that all have 5 star USRC resiliency rating, connected to a transportation lifeline (to prevent Christchurch type encapsulation) and to link to critical facilities, like hospitals, if needed.
The designated area would have its own emergency back up power generation, water purification, waste treatment and security forces. It would be a safe go-to zone that could continue to maintain functionality after a major event like an earthquake while the remainder of the city around it was recovering.
“This is not totally far fetched,” explains Professor Bruneau. “In the US we have a lot of what are called ‘gated communities’ where they set their own rules for things such as architectural finishes or lifestyle features. Another great example is Walt Disney’s EPCOT.”
Professor Bruneau is talking about the Experimental Prototype Community of Tomorrow – a futuristic utopian city brought to life as an educational theme park at the Walt Disney World Resort.
In Disney's words, "EPCOT would take its cue from the new ideas and new technologies that emerge from the creative centre’s of American industry. It would be a community of tomorrow - never completed but always introducing, testing and demonstrating new materials and new systems.”
Not unlike the innovative work of our own Quake Centre and earthquake engineers like Professor Bruneau, relentlessly researching, testing and pushing the boundaries of future possibilities, opportunities and expectations in earthquake resilience.
Perhaps the lifeline building district is not such a crazy idea after all.