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Mr. Luddite

On 3/24/2015 12:24 PM, wrote:
On Tue, 24 Mar 2015 11:26:34 -0400, Keyser Söze
wrote:

On 3/24/15 10:35 AM, Mr. Luddite wrote:
On 3/24/2015 10:23 AM, wrote:
On Tue, 24 Mar 2015 08:47:25 -0400, John H.
wrote:

I think Greg forgets that I spent three winters living in Florida where
there were many bridges and overpasses. I never saw sand blasting and
repainting of any of them. I am sure it happens from time to time but
not to the extent that you see in the northeast. During the summer
months there are crews out constantly sand blasting and repainting the
bridge and overpass structures.

Probably a lot more of your basic concrete beam bridges which don't
require
repainting regularly - too many kids with spray cans keep them
freshly painted.

The problem with the prestressed concrete beams is the salt water
infiltrates the beam and gets to the rebar.. A little rust on that
rebar will blow that beam out as fast as a series of freeze thaw
cycles.

I do find it amazing that this many "boaters" are blowing off the
effects of 24/7/356 salt water corrosion in sub tropical water.
Richard mentioned cars ... OK how many Florida boats are that
attractive, even to Chesapeake Bay boaters, much less someone near
Tim.

If road salt is that deleterious to the structure UNDER your bridges,
maybe you should be looking at how you engineer bridges to see how the
salt is getting there and why it isn't harmlessly going out the
scuppers and over the side.,

I don't question how bridges are designed to withstand the elements.
There are people far more qualified than you or I that do that.

You obviously missed the article in the Boston Globe announcing that
Gregg has been hired by the Harvard School of Medicine to teach courses
on "There is no need for trained, experienced, educated doctors," and
"Tips on Performing Your Own Heart Surgery." These are only taught by
the world's greatest living expert.

If road salt is that big an issue even a dumb old guy like me knows
you should be designing your bridges to send that salt over the side
and not send it up under the bridge .

I don't know why bridges are designed as they are. Most around here are
steel I-Beam frames on concrete forms. Perhaps they don't want heavy
rains to cause water or runoff from pouring down on whatever is under
the bridge .... like cars traveling at 70 miles per hour on a highway.

All I know is during the summer it is routine to see half of a highway
blocked off while a crew is sandblasting and then repainting the steel
frames of bridges. The only type of construction work on bridges in
Florida that I ever saw was new construction and changes to roadways.
Come to think of it, I never even saw any repaving being done although I
am sure it is done from time to time.