Currently, building codes and standards are focused on protecting life safety during major environmental hazards, not trying to mitigate the amount of time that buildings are unusable. The one exception to this is a class of buildings designated as essential facilities, such as hospitals, emergency operation centers, police and fire stations. Those buildings are typically designed to return to function very quickly following a major hazard. This binary approach may not be best for a community. For example, there are probably some buildings which need only provide safety and not collapse, but there are others that would have a major impact if they were rendered uninhabitable. Housing is one major class, as are schools and essential retail like grocery stores, hardware stores and banks. They may be off-line for the initial 72 hours, but their continued loss will have impacts on how quickly a community can recover.
However, there is a new way of thinking that is gaining momentum within the profession which seeks to design to minimize downtime, classing buildings in different bins based on their function and their need for a community to recover. The first time that an overarching framework for buildings and life line systems based on return to operation was put forth was in the SPUR Resilient City project, which Robert Pekelnicky of Degenkolb Engineers was a leading contributor to. The SPUR method classified building clusters into bins of return to function within hours, days, weeks or months. Essential facilities are still required to retain their pre-event function within hours after the event. Housing should be capable of allowing people to shelter safety within, even if power and water are not restored for a couple days. Essential retail should be back up, to allow people to get basic supplies, within 3 to 7 days. Many of SPUR’s recommendations have made their way into the San Francisco Earthquake Safety Implementation plan, a multi-year plan currently being implemented to improve the City’s resilience to a major earthquake. The State of Oregon undertook a similar effort focusing on a major Cascadia subduction earthquake and tsunami and developing recommendations for local jurisdictions to implement.
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