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RE: URM Building with Additional work

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Your question raises an issue more of Psychological safety 
verses increase strength. In my opinion, no mater what you do to 
this building short of removing the URM walls and replacing them 
with reinforced materials will not make the building anthing 
other than a hazardous structure.
The purpose of Division 88 (RGA ) is for Hazard Reduction - not 
elimination. Without changing the structural system of this 
building, you would find it difficult to design a secondary 
system that would prevent the failure of brick. If you shotcrete 
the exterior, you may loose the inner wythe to the interior in a 
bad enough shake.
The big issue is ecconomic. Most of these multi-story URM 
structures were used for low income apartments and transient 
hotels. The more money you place into retrofit, the less money 
the investor will get on his return. At some point the rents or 
market value will be exceed comparable values for the area.
Finally, the work done in Los Angeles has been shown to do what 
it was designed for - save lives. The code never guaranteed the 
building would be salvagable, but was intended to maintain the 
structural integrety of the building long enough for the 
occupants to get safely out. After that, the building may be 
repaired or torn down.
Remember, the cost of retrofit at $10.00 to $20.00 per square 
foot is much cheaper than new construction and maintains 
affordable housing without displacing thousands of people would 
could not afford comparable housing.
I would try to explain this to my client so that they understand 
that "A hazardous building, but any other name is still a 
hazardous building".

Dennis S. Wish PE