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Haiti earthquake revealed the terrible cost of poor building design
Contrary to appearances, most residential brick facades are non-structural, providing little lateral stability, and they are likely to crack and fall apart during an earthquake. A seismic event will shake and deform a home's wood skeleton, but collapse is avoided because wood framing and carpentry connections can flex without coming apart. Look at aging country barns.
The technique of isolating a building from ground movement is effective but costly. Keeping a building motionless while the ground shifts requires a foundation surrounded by specially engineered isolation pads and shock absorbers that separate the building from the earth. When the ground shakes, the isolators enable the building to stay put because of its inertia. Increasingly, this technique is used in active seismic zones, such as the West Coast, both for new buildings and to retrofit older ones.
In Haiti, buildings of all ages, shapes and sizes were unable to remain standing when struck by a magnitude-7 earthquake, suggesting that none of these techniques were correctly used. Undoubtedly, many damaged or collapsed buildings were erected without professional design or construction help. Equally problematic, many of the fallen structures stood on unstable soil and excessively steep sites especially vulnerable to seismic activity.
Evidently, Haiti's building codes were inadequate and unenforced. This is all the more tragic because it has long been known that the island of Hispaniola, astride two major seismic faults, is susceptible to earthquakes. Sadly, Haiti is destined to experience more seismic events, as powerful or more powerful than the Jan. 12 earthquake.
In the end, it's hard to avoid comparing Port-au-Prince and New Orleans, the former atop colliding tectonic plates and the latter sitting below sea level. The comparison elicits an inescapable observation: If we could start from scratch, we probably would choose neither location for building a modern city, despite all our modern construction technology.
Roger K. Lewis is a practicing architect and a professor emeritus of architecture at the University of Maryland.