Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Housing Performance Objectives

[Subject Prev][Subject Next][Thread Prev][Thread Next]
In a message dated 97-12-05 19:04:41 EST,  you write:

> We sell the public as home that is earthquake and wind resistant. They are
> aware what this really means, nor are they concerned since they purchase
> a basic trust that they are protected by laws. I doubt that they consider 
> that there is a large grey area in the application of these laws that
> a lower standard of safety 


I thought this thread had ended, but you raise an important point that merits
a reply.  We (both the engineering and code enforcement communities) need to
do much more to improve public awareness of the building performance
objectives and expectations stated in UBC 1624.1, and the assumptions and
cost-benefit trade-offs these reflect.   When I've done this at meetings and
in talks to audiences, people almost always understood, and accepted it, if
sometimes grudgingly.  I draw a parallel between earthquake and fire
*resistant* structures versus mythical earthquake and fire *proof* structures.
Folks intuitively understands that fire losses can't be eliminated unless we
are prepared to live in the proverbial concrete bunkers, with the attendant
restrictions on architectural expression and increased construction costs that
would result;  and I further point out that, even then, we'd need to sprinkler
all buildings to minimize losses to possessions (omitting for the moment the
significant water damage from activated sprinkers).  The 30 to 50 thousand
fire deaths in this country *annually* throughout this century, plus the
countless millions of dollars of fire losses annually, certainly generate
public concern, but there haven't been outrage to any extent.  This is largely
because people have the common sense to understand that trade-offs are needed,
that we can't eliminate all fire damage and casualties (by 'people', I exclude
the fire service and their mantra of "zero tolerance for unsprinklered
buildings"), unless we are prepared to make unacceptable trade-offs, including
possibly higher taxes to put a fire station on each block.  When this parallel
is drawn, people can relate that to the necessity for some trade-offs in
building seismic performance as well.

Efforts such as SEAOC's Vision 2000 may someday give us the tools to reliably
predict seismic performance, and an owner who wants performance above life
safety can select a level for the engineer to design the project to.   Until
then, we need to get out the message of 1624.1 at every opportunity, both to
the public as well as to our clients.

Frank Lew, SE
Orinda, CA