Carbon fiber bridges.....

Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces. If steel breaks due
to contraction and expansion maybe they
should use some other material, like CF.

In article ,
Crescentius Vespasianus wrote:

Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces. If steel breaks due
to contraction and expansion maybe they
should use some other material, like CF.

Don't give them ideas. Or CF prices would go further up and affect our
bike affordability.
--

Artoi wrote:
In article ,
Crescentius Vespasianus wrote:

Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces. If steel breaks due
to contraction and expansion maybe they
should use some other material, like CF.

Don't give them ideas. Or CF prices would go further up and affect our
bike affordability.
--

bs. $120 for a carbon fork is not too expensive.

Crescentius Vespasianus wrote:
Heard a report that the Minneapolis bridge collapsed due to the effect
on steel that the extreme temperatures in that area produces. If steel
breaks due to contraction and expansion maybe they should use some other
material, like CF.

bridges have expansion joints, so that's not the issue. [cold
temperature] brittle transition can be an issue, but that's /most/
unlikely to be the case in summer.

much more likely, the combined effects of poor maintenance, subsequent
corrosion, and when sufficiently advanced, fatigue. preventable.
lamentable. shameful.

On Aug 5, 7:02 pm, Crescentius Vespasianus
wrote:
Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces.

Don't believe everything you hear - or read. The coefficient of
expansion for common building materials is well known and taken into
account when the structure is designed. That's why you see and feel
the bumps from all of those expansion joints when you drive across a
bridge.

R

On Sun, 05 Aug 2007 16:02:06 -0700, Crescentius Vespasianus
wrote:

Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces. If steel breaks due
to contraction and expansion maybe they
should use some other material, like CF.

Even if we swallow the unlikely premise, the only bridge design which
would make use of Carbon fibre's virtue would be one requiring high
tensile strength and stiffness per weight. It has been proposed to use
CF cables for extremely long span suspension bridges.

Kinky Cowboy*

*Batteries not included
May contain traces of nuts
Your milage may vary

RicodJour who? wrote:
On Aug 5, 7:02 pm, Crescentius Vespasianus
wrote:
Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces.

Don't believe everything you hear - or read. The coefficient of
expansion for common building materials is well known and taken into
account when the structure is designed. That's why you see and feel
the bumps from all of those expansion joints when you drive across a
bridge.

Some bridge expansion joints are wide enough to trap a typical road tire
- instant header.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful


--
Posted via a free Usenet account from http://www.teranews.com

"RicodJour" wrote in message
ups.com...
On Aug 5, 7:02 pm, Crescentius Vespasianus
wrote:
Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces.

Don't believe everything you hear - or read. The coefficient of
expansion for common building materials is well known and taken into
account when the structure is designed. That's why you see and feel
the bumps from all of those expansion joints when you drive across a
bridge.

It's something railways people still get caught by though - and not just UK
ones!

cheers,
clive

Crescentius Vespasianus who? wrote:
Heard a report that the Minneapolis bridge collapsed due to the effect
on steel that the extreme temperatures in that area produces. If steel
breaks due to contraction and expansion maybe they should use some other
material, like CF.

The only places where carbon fiber reinforced polymer (CFRP) generally
makes sense is where lower weight is a primary goal (e.g. racing
bicycles) or where the use offsets a greater expense (e.g. CFRP cost
more than aluminium alloy for aircraft construction, but results in
lower fuel consumption).

A CFRP bridge superstructure would only result in some savings in
foundation size (however, less than proportional to the weight reduction
due to similar wind overturning loads). The additional superstructure
cost of replacing steel with CFRP would be far greater than the lower
foundation cost.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

--
Posted via a free Usenet account from http://www.teranews.com

On Aug 6, 7:30 pm, "Tom \"Johnny Sunset\" Sherman"
wrote:
RicodJour who? wrote:
On Aug 5, 7:02 pm, Crescentius Vespasianus

Heard a report that the Minneapolis
bridge collapsed due to the effect on
steel that the extreme temperatures in
that area produces.

Don't believe everything you hear - or read. The coefficient of
expansion for common building materials is well known and taken into
account when the structure is designed. That's why you see and feel
the bumps from all of those expansion joints when you drive across a
bridge.

Some bridge expansion joints are wide enough to trap a typical road tire
- instant header.

They're put there so you can practice bunny hopping your bike.

R