The concept of designing structures and systems to achieve a desirable and a safe level of resistance for earthquakes and other natural hazards has been around for a long time. In California and Japan, for example, the concept started developing in earnest after the 1906 San Francisco and the 1923 Tokyo earthquakes. More specifically, the response to the 1933 Long Beach, Calif., earthquake redefined the concept of structural resilience for buildings.
In the sphere of earthquake engineering, including seismology, the current system of code development and code enforcement makes it difficult to achieve resilience beyond basics like life safety. For earthquakes, the conventional building codes are not geared towards resilience, at the right cost, but towards life safety. Conventional buildings, from individual houses to the biggest buildings and high-rises, are designed to protect lives and are expected to suffer damage.
The codes are not yet driven by resilience. Worse, code development is often driven by compromises over political (i.e., material or manufacturer) special interests, rather than purely engineering concerns. That impedes our ability to improve resilience. Codes are also not driven by long-term and societal cost-benefit considerations and concerns with longevity. We, engineers, have learned that a higher level of design provides additional resilience, but we have not quantified the benefits. In the current environment, engineers are not expected to do that. The problem is that no one is expected to quantify the cost-benefit and apply it in a reasonable or optimal way to conventional buildings. In effect, no one oversees the optimal resilience of buildings for earthquakes.
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