
The Mystery of the Brand-New Bay Bridge's Corroded Steel - qzervaas
http://www.wired.com/2015/06/mystery-brand-new-bay-bridges-corroded-steel/
======
msandford
Sounds like they got a bad batch of steel or something. Corrosion doesn't
cause steel to become brittle. It weakens it, yes, but it does so by reducing
the cross-section. Corrosion doesn't materially alter the bulk properties of
the metal, only the amount of metal in the bulk.

I get that there's corruption and shortcuts getting taken everywhere on big
projects like this. But it's still surprising that better QA/QC isn't done.
There's going to be a lot of finger pointing on whose fault this is.

~~~
devindotcom
Yeah, I can imagine lax quality control if you're making... I don't know, a
desk or even a house, but a bridge? Whoever dropped the ball put a HELL of a
lot of people (and money) in jeopardy - even if the corrosion isn't going to
critically affect the structure, it makes one wonder about the quality of the
rest of the materials, and the contracts involved...

~~~
oh_sigh
Well, the construction of the bridge decks and the materials for the bridge
was made in China...

~~~
sneak
So are Apple Watches and iPads. Please stop it with this nonsensical
nationalism/racism.

~~~
x0x0
It's well known that china has lax safety and quality standards. See for one
of many examples the adulterated pet food from china or the milk scandal where
china poisoned 300,000 infants [1]. To this day, China's own citizens import
milk for their children if they can [2]. Or chinese drywall [3]. It's merely
prudent to safety test food and materials imported from China.

[1]
[http://en.wikipedia.org/wiki/2008_Chinese_milk_scandal](http://en.wikipedia.org/wiki/2008_Chinese_milk_scandal)

[2] [http://www.bloomberg.com/bw/articles/2014-11-16/china-
turns-...](http://www.bloomberg.com/bw/articles/2014-11-16/china-turns-to-the-
u-dot-s-dot-and-australia-to-import-safer-milk)

[3]
[http://en.wikipedia.org/wiki/Chinese_drywall](http://en.wikipedia.org/wiki/Chinese_drywall)

~~~
prewett
China also has had a bunch of spectacular construction failures. My favorite
is the Shanghai bridge made out of styrofoam and garbage [1], but there are
other, less spectacular examples: [2]. The schools in Sichuan are notable for
poor construction, as many schools feel down but adjacent buildings did not.
[3] Apparently one builder would tap the cement on inspection, and if it
didn't ring right, he would make the contractor redo it. They didn't like him
much, but his schools stayed up. Can't find the article, though. Apparently
the rebuilding isn't any better [4].

I wouldn't even consider using Chinese construction material.

[1] [http://www.weirdasianews.com/2010/02/05/shanghai-
wonderbridg...](http://www.weirdasianews.com/2010/02/05/shanghai-wonderbridge-
trash-collapses/)

[2] [http://world.time.com/2012/08/27/bridge-collapse-in-china-
ra...](http://world.time.com/2012/08/27/bridge-collapse-in-china-raises-
questions-about-safety-of-countrys-road-construction-boom/)

[3]
[http://www.nytimes.com/2008/05/25/world/asia/25schools.html?...](http://www.nytimes.com/2008/05/25/world/asia/25schools.html?pagewanted=all)

[4]
[http://www.npr.org/sections/parallels/2013/05/14/183635289/F...](http://www.npr.org/sections/parallels/2013/05/14/183635289/Five-
Years-After-A-Quake-Chinese-Cite-Shoddy-Reconstruction)

------
kevlened
Relevant discussion over a year ago:
[https://news.ycombinator.com/item?id=7866795](https://news.ycombinator.com/item?id=7866795)

Senate report: Caltrans ignored shoddy work on Bay Bridge in China and U.S.
[http://www.sacbee.com/news/investigations/bay-
bridge/article...](http://www.sacbee.com/news/investigations/bay-
bridge/article2589402.html)

Californians pay for Bay Bridge flaws, but wind farm recoups costs from same
contractor [http://www.sacbee.com/news/investigations/bay-
bridge/article...](http://www.sacbee.com/news/investigations/bay-
bridge/article4748610.html)

------
mapgrep
Multiple civil engineering professors have been raising concerns over this
issue since at least 2013.

[http://alumni.berkeley.edu/california-magazine/just-
in/2014-...](http://alumni.berkeley.edu/california-magazine/just-
in/2014-10-10/bridge-over-troubled-bolts-uc-berkeley-experts-raise-safety)

[http://alumni.berkeley.edu/california-
magazine/summer-2013-n...](http://alumni.berkeley.edu/california-
magazine/summer-2013-new-deal/troubled-bridge)

------
jedmeyers
Very informative video on the basics of Charpy Impact Test:
[https://www.youtube.com/watch?v=tpGhqQvftAo&ab_channel=Mater...](https://www.youtube.com/watch?v=tpGhqQvftAo&ab_channel=MaterialsScience2000)

------
pasbesoin
I seem to recall one of the cost saving measures, coming with some
controversy, being to use Chinese steel, at least in part. Perhaps I am
incorrectly remembering this.

I would be interested in knowing the source of these components (which the
rather long-winded article does not get around to providing).

~~~
mikeyouse
The bolts were made in Ohio and finished elsewhere in the U.S. They never left
the country.

------
spiritplumber
I wonder if an electrical circuit has happened between the salt water and the
various sections of the bridge...

~~~
stephengillie
Perhaps during an electrical storm. Unless you think there's a long-term high-
voltage short that nobody's noticed?

Welders use Phosphoric acid and an electrified scrub brush (electrified lead
wrapped with tough cloth, dipped in Phosphoric acid) to scrub welding scorches
off of brushed stainless steel. Phosphoric acid on its own will etch stainless
steel (and teeth), and electrifying the set dramatically increases the
reaction rate, leaving bare metal after a couple of gentle passes.

~~~
benzofuran
There's most certainly a cathodic protection system on the bridge for the
rebars and supports exposed to seawater, however if pooling water wasn't
intended in the lower areas then there was likely no CP active in the area -
and the protection of the other members may have accelerated corrosion
elsewhere due to stray current interference.

edit: It's actually the low voltage corrosion cells that you need to be
cognizant of in such a case - most high voltage shorts fail before significant
corrosion has taken place. Consumption rates for steel are in the kg/A-yr
scale, and the concentration of the current dump is a major factor in general
vs acute/pitting corrosion activity.

~~~
spiritplumber
Yeah. If you get this stuff on a new boat or barge, you have to basically send
around guys with voltmeters with really long leads, all over the ship... if I
was in charge of the bridge I'd do that. It's relatively inexpensive, and
either finds the problem or gets rid of one common variable.

~~~
benzofuran
This is what I do for a living actually - and concrete / mixed structure
corrosion control is unfortunately a lot more expensive and difficult than
single structure (ie steel hulled vessels). A typical concrete CP system will
be low output but with dozens to hundreds of individually controlled zones and
reference electrodes to monitor the system performance.

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redwood
To me the fact that the bridge took 15 years to build --- perhaps the longest
major bridge project --- is probably related.

------
comrade1
The u.s. seems to be increasingly modeling itself after banana republics and
corrupt third-world countries, so it's no surprise that someone shorted the
project with bad steel and pocketed the difference.

------
Animats
They don't mention the steel supplier. It was Zhenhua Port Machinery Co., in
Shanghai.[1] They usually make port cranes, not bridge parts.

[1] [http://www.sacbee.com/news/investigations/bay-
bridge/article...](http://www.sacbee.com/news/investigations/bay-
bridge/article2589402.html)

~~~
batbomb
There's a lot of parts in the bridge. The rods aren't supplied from Zhenhua,
they are from Dyson Corp. of Ohio.

[http://www.sfgate.com/bayarea/article/Bay-Bridge-supplier-
fa...](http://www.sfgate.com/bayarea/article/Bay-Bridge-supplier-failed-to-
reveal-rods-6037844.php)

~~~
Animats
Oh. Thanks.

