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Code for Thought

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At yesterday's California Building Standards Commission's Code 2000
Partnership meeting, the subject of seismic safety in the model building codes
was again broached. The Partnership is charged with recommending future model
building codes to the Commission - i.e. the potential replacement(s) for the
UBC. SEAOC representatives Norm Scheel and Tom Hale raised the concern of
low/moderate seismic provisions in the 2000 International Building Code (IBC)
not being consistent with long-accepted west coast practices. Much of the
state's growth is in regions with moderate and low seismicity comparable to
parts of the Midwest U.S. 

Unfortunately, the state has no easy way to adopt amendments to the model
codes that would apply to all occupancies. The only option short of
legislation is to approach each and every local government city council/board
of supervisors and ask them to amend the code via local ordinances. But there
are over 300 such affected entities, so this option is impractical. An example
of how this system "worked" is how long it took to enact the steel moment
frame emergency code change in 1994-6. Only the most enlightened, staffed
cities can give issues like this proper consideration.

For example, the Midwest's U.S. concept of minimally reinforced masonry and
concrete walls is to put vertical bars at 10 feet on center. Here in
California, we'd call that unreinforced unless the bar spacing was 4 feet or
less. Unreinforced concrete and masonry has essentially been banned for the
past 65 or so years in California. There are many other low/moderate seismic
provisions in the IBC that are also concerns. 

The participants discussed two options: 1. Legislation to authorize a state
agency to adopt seismic amendments to the model code that would apply to all
occupancies. Local building officials and others don't like this option. Its a
slippery slope that may lead to widespread amendments to the model code. 

2. Sponsor "narrow" legislation that would make IBC's Seismic Design Category
D (ductile detailing, essentially, for you New Zealanders) the minimum
statewide.  There seemed to be head-nodding for this option, including from
those representing local govts, development and building owners. It would
allow the Building Standards Commission no discretion or flexibility. This
would still likely be a very difficult bill to get though the gauntlet. A
benefit/cost study would be helpful, if not necessary for passage of such a
bill.  

While this may seem to be a problem that will show up far into the future - 4
years (??) , a solution to the problem could also take years. 

BTW, Norm and Tom did a great job in these last two meetings stating SEAOC's
concerns. 

What do you all think of these two options? Are there other possible options?

Fred Turner, Staff Structural Engineer
Ca. Seismic Safety Commission, 1900 K St. #100 Sacramento, CA 95814    
916-327-1606     916-322-9476 Fax      FredT5(--nospam--at)aol.com