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Re: bay bridge

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Ok, but how many planned attacks of that nature have taken place on even
"key" bridges in the past?  What is next?  How do you prevent some moron
terriorist from just deciding to get that semi-truck going 100 mph or so
and ramming a bridge column of a "key" bridge?  Fire suppression/proofing
won't stop that.  How are you going to stop that terriorist from driving a
car bomb under that bridge and collapsing from an explosion?  The point is
that there is limited amount of funds to do such measures and repairs.
Looking at this one incident in isolation is a nice easy thing and can
easily lead one to a conclusion that it worth the extra cost for fire
proofing...but what about the other scenarios that can cause just as much
damage to such a bridge?

And as to buildings, that is apples and oranges.  First of all, fire in a
building is MUCH more a life safety issue than it is to a bridge.  But,
even then, a much less severe fire in a building can cause much more
damage than that tanker truck fire did to that bridge.

And finally, how do you know that a fire proofing/suppression would have
made a difference?  It is entirely possible that the fire was burning so
hot due to the huge amount of fuel that a 1 or 2 hr rating by way of fire
proofing may not have really made difference.  Remember that such ratings
systems make use of "standard" fires which tend to burn with less heat
than a fire that is fueled by a ton of gas.

Regards,

Scott
Adrian, MI


On Wed, 2 May 2007, S. Gordin wrote:

> Scott,
>
> We put fire supression system in basically every building.  IMO, such system is appropriate for unique bridges that are not that many (Bay, Verrazzano, Golden Gate, etc.).  And I meant not an freak tanker accident, but some possible (to say the least) planned act.
>
> V. Steve Gordin, SE
> Irvine CA
>
>   ----- Original Message -----
>   From: Scott Maxwell
>   To: seaint(--nospam--at)seaint.org
>   Sent: Wednesday, May 02, 2007 08:57
>   Subject: Re: bay bridge
>
>
>   If you look only at this situation, then it might be cost and time
>   efficient.  But, you need to look at all cases.  How many times has a fuel
>   tanker crashed and produced a fire that is hot enough to weaken the steel
>   and collapse a structure?  So, now does using fire protection on ALL steel
>   bridges across the country really look that cost efficient?  You have one
>   incident at one bridge when there are years and years of tons of steel
>   bridges in service.  So, yes...you might save some money in not having to
>   rebuild this "bridge" (and Mark, many people consider a horizontal span of
>   highway to be a bridge even it is NOT really the Bay Bridge) but how much
>   more money are you going to end up spending on bridges that don't and
>   never have been hit in such a situation that a fire could cause a section
>   of the bridge to collapse.  You willing to have your taxes increased to
>   put fire protection on all those bridges (hell, we cannot even just pay
>   for maintance of our roads and bridges here in Michigan without more money
>   [aka taxes]) due to one incident at one bridge over how many years?  Good
>   luck on that one.
>
>   It is the same reason why we don't design every building to that level
>   that we design hospitals for seismic events.
>
>   Regards,
>
>   Scott
>   Adrian, MI
>
>   On Wed, 2 May 2007, S. Gordin wrote:
>
>   > Mark,
>   >
>   > You are right, but the condition may be extrapolated...
>   >
>   > It appears that an effective overlapping system of fire suppression is warranted on all bridges, especially, on the steel structures.  In the current situation, it may be a worthy, relatively cost- and time-effective investment into the infrastructure.
>   >
>   > V. Steve Gordin, SE
>   > Irvine CA
>   >
>   >
>   >
>   >   ----- Original Message -----
>   >   From: Mark Gilligan
>   >   To: seaint(--nospam--at)seaint.org
>   >   Sent: Wednesday, May 02, 2007 08:13
>   >   Subject: Re: bay bridge
>   >
>   >
>   >   The Bay Bridge is still standing.
>   >
>   >   The damage occured to some of the elevated structures
>   >   at the East end of the bridge where several freways
>   >   intersect.
>   >
>   >   Mark Gilligan
>   >
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