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Re: Tangshen

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In a message dated 98-05-25 02:08:14 EDT, wish(--nospam--at)cwia.com write:

>  In one respect, the comparison is justified. It took almost fifty years for
>  the State of California to adopt a Hazard Mitigation Law that would go back
>  and retrofit all the URM's constructed prior to 1933. If we knew from the
>  Long Beach Earthquake that URM's are unsafe, why did it take 50 years to
>  improve their performance?

There is no State law that mandates retrofit of UMBs, unless one has been
enacted in the last year or so, since my retirement (Fred Turner?).  If you
are referring to SB547 (1986), that chaptered legislation required only three
actions by local governments.  1) identify all UMBs in their jurisdictions;
2) establish a mitigation plan that may be as little as notifying UMB owners
that this type of building construction has performed poorly in past
earthquakes; and 3)  provide to the Seismic Safety Commission by the end of
1989 a list of UMBs identified, and the mitigation plan adopted.  Some
jurisdictions adopted mandatory retrofit ordinances, some adopted policies to
encourage voluntary retrofits, and some took no official action.  The SSC has
made some progress since then in applying pressure on UMB owners, at least on
paper.  For example,  owners of commercial UMBs now must provide some SSC-
developed information to prospective buyers, as well as post warning placards
on their buildings (AB1963 - 1992).  Readers desiring more details can read
SSC 95-05 - "Status of the Unreinforced Masonry Building Law" (Fred - is there
a later edition?).

>  In 1992 (or there about)California passed Assembly Bill 200 (Frank you
>  remember the Triple R committee). AB200 identified that over 1.3 million
>  single family homes in California constructed before 1969 may have
>  structural deficiencies related to cripplewall failures or improper
>  anchorage to their foundations. Why did this become a law when so few lives
>  were lost in single family homes.

I no longer  have ready access to West's and Deering's annotated California
Codes, or the collection of bills and chaptered legislation I accumulated over
the years.  And the way the State server is set up, it's not possible to
search on bill numbers as far back as 1992.  I don't know anyting about AB200.
However, I suspect you are again mistaken, for it sounds like you believe
there is a State statue that requires seismic retrofits for single family
dwellings in accordance with the Triple R report or UCBC Appendix Chapter 5.
There is none.  The Committee developed the document to allow building
departments to provide some consistent guidance to homeowners seeking
information on voluntary retrofits of their homes.  It wouldn't have surprised
committee members if some jurisdictions adopted mandatory retrofit programs
based on this appendix, but that was not a significant goal of the committee.
>  
>  One bigger questions: In addition to the 1.3 million SFR with structural
>  defects, there are many thousands of multi-residential apartment buildings
>  and condo's that have the same deficiency. Why were these buildings
>  purposely omitted from the rhetoric of AB200?   I have inspected these
>  buildings in Los Angeles - they do exist and are a greater risk. BTW,
wasn't
>  Northridge Meadows one of the types of cripple wall structures? It is my
>  belief that they are omitted because of the lobby power of Apartment
>  building owners who have their own coalition. I also understand that it was
>  necessary to omit these buildings in order to pass AB200.
>  Still, thousands of lives are endangered because of the power of the
>  Building Owner in state politics.
>  

If indeed AB200 referenced UCBC Appendix Chapter 5, then multi-family
buildings could not be covered under the bill.  The appendix explicitly limits
its use to single family dwellings.  That's because homeowners or their
contractors can comply with these prescriptive standards without having to
obtain the services of design professionals.  That's consistent with the
exemption for design of  SFDs from BORPELS and CBAE jurisdictions.  In
contrast, for buildings that are required to have an AOR or EOR, the retrofits
should also be performed by professionals.

>  Conversely, single family URM structures are omitted from compliance with
>  the State Hazard Mitigation codes - why? It is not a state requirement to
>  force compliance of a SFR even if it is known to be constructed of
>  unreinforced masonry or adobe. The answer is both statistical and
political.
>  In either case, those with the most money can easily defeat those without.

This is your third strike in this e-mail, and you're out.   Most deaths and
injuries caused by UMB failures have occurred when the masonry walls fall
*outward*, and rain debris on outside passers-by below, or through the lower
roofs of adjacent buildings.  Casualties within residential UMBs have been
much smaller, in no small part due to the interior partitions acting as
spacers to keep floors and roofs from pancaking.  One explanation for the
exemption of single family UMBs from SB547 is that such structures typically
have front-yard and side-yard setbacks such that passers-by and adjacent
neighbors are unlikely to be at risk from wall failures.

>  Even when life safety is the issue, codes are stonewalled from reaching
>  fruition because of the financial power coming from stronger lobbyist. Once
>  again, money rules over those without - even in life safety issues.

Your indictment, while harsh, has some merit with respect to building safety,
and to many other facets of life and commerce as well.  But surely, as a
grandfather, you've enough life experiences by now to not be surprised by this
reality.

Frank Lew, SE
Orinda, CA