Originally Posted By: Arney
Originally Posted By: hikermor
Retrofitting is expensive, a real hassle, and it won't necessarily ensure the survival of the building, but the occupants are more likely to live. In that sense, the Napa quake retrofit was successful.

Hikermor has a good point about what the point of most seismic retrofitting is. I think the popular understanding is that it makes an old (sometimes VERY old) brick building with old, crumbly mortar impervious to earthquake damage, but that is generally not the case. Most retrofitting jobs seem to be intended to prevent the structure from collapsing onto occupants during the quake itself. Beyond that, such as whether the structure is still functional/habitable, is a whole different matter.

So, I think the news I see is doing a disservice when it reports that retrofitting "failed" when it may have actually done exactly what it was intended to do. Just because a structure is damaged (sometimes severely) and becomes red tagged does not mean the retrofitting failed, unless the job was specifically designed do just that.
Yes and no. You are correct that many (most?) retrofits of old buildings are meant to protect life & limb, not necessarily keep the building useable after the quake. However, protecting life and limb also includes people outside the building injured by falling debris. As the article I linked noted, had the quake happened at other times of day there easily could have been dozens killed and injured in the wine bar on the sidewalk below the building. But then again, as the article also notes, there is simply no economically feasible way to reinforce the brick facade on many of those old buildings. We can only try to do the best we can with old buildings, and accept some risk.

Along the same lines, here is an article about the boy who was badly injured by a collapsing fireplace. Most people who are injured in earthquakes (at least in 1st world countries) are not hurt by the whole building collapsing, but rather by falling stuff inside the building. There is a reason that the experts recommend Drop, Cover, and Hold!
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