They Ain't Chinese!

"When a fastener contains a critical mass of hydrogen before installation, it usually fails in less than 24 hrs...."

"Hydrogen can be introduced during acid cleaning,pickling,electroplating, or exposure to hydrogen rich environment....This type of failure is most common in bolts Rockwell hardness C36 and above..."

I would check to make sure this company has experience and successful track record with this type of bolt and the special handling it requires.....

Reference...

Are we sure it's not Chinese bolts?

http://www.npr.org/2011/09/16/140515737/california-turns-to-china-for-new-bay-bridge

Something doesn't seem right here. I wonder if someone pulled a switcheroo:

The bolts, also referred to as rods, attach the four shear keys and four bearings between the easternmost pier of the new suspension span and the roadway above it. The devices were made by the Korean firm Hochang Machinery Industries, but the bolts were made in the United States, according to Caltrans. The agency did not identify the U.S. manufacturer.

Read more here: http://www.sacbee.com/2013/03/27/5298105/broken-bolts-on-new-bay-bridge.html#storylink=cpy

Could it be that the steel itself was imported from China, and fabricated in the US....and would it matter?

In a new campaign dubbed, "Should Be Made in America" the group has set up billboards along Interstate 880 that depict the Chinese flag with the words "The Bay Bridge 100% Foreign Steel."

Bay Bridge spokesperson Bart Ney disputed the accuracy of Paul's claims and said 70 percent of the steel being used for the new span is fabricated in America. Ney said foreign companies are used out of necessity for some parts of the project.

http://sanfrancisco.cbslocal.com/2012/03/26/manufacturing-group-protests-chinese-steel-used-in-bay-bridge-construction/

Edit: Nevermind.

http://www.sfexaminer.com/local/2013/03/bad-bay-bridge-steel-rods-originated-ohio - sorry, link no longer available

Talk about an "Oh CR4P" moment.

"Because the rods are buried deep in the concrete, many of them cannot be removed. Engineers likely will have to develop an alternative system for stabilizing the span. Caltrans possibly will need to construct an exterior harness that would have the same stabilizing effect, Anziano said. The cost of such a project is not yet known, but it could be billed to the manufacturer that provided the steel, according to Heminger."

Read more at the San Francisco Examiner: (http://www.sfexaminer.com/local/development/2013/03/bay-bridge-bolt-problem-arose-quality-control-lapses-officials-say#ixzz2P88wI0xQ - sorry, link no longer available)
The plot thickens,,,,.
"Though Dyson produced the bolts, the San Francisco Chronicle's story said it may not be responsible for the failures. Other companies galvanized the bolts to protect them against corrosion, and imperfections may have been introduced into the bolts at that step in the process.

Tony Anziano, Caltrans' toll-bridge program manager told the Chronicle that Dyson has two galvanizing subcontractors. He did not identify the companies.

Caltrans said hydrogen was found in the rods. The Chronicle reported that hydrogen from water or other contaminants can migrate into steel during galvanization, a process of dipping steel into liquid zinc. "

http://www.cleveland.com/business/index.ssf/2013/03/painesvilles_dyson_corp_linked.html

Sounds expensive.

I'm betting that the companies that provided the bolts, don't have the cash for the repairs. They will likely have a hard time getting their insurance company to pay also.

Having run some fairly large projects in my life, this whole story just gives me the jitters.

I couldn't imagine being in the shoes of the QC people right now. I'd be looking for a big rock to hide under.

Well maybe it's not so bad after all.....

"There are a total of 288 concrete encased rods; nearly one-hundred rods were tensioned and inspected, one-third of which need replacing. The bolts were installed in 2008, but crews have just started tightening them. The remaining bolts, located further below the deck on the same pier, have yet to be tensioned.

Caltrans had previously performed quality assurance tests alongside Painesville, Oh.-based bolt manufacturer Dyson Corp., but not all rods were tested, which is a common industry practice.

"We have surmounted far greater engineering challenges than this one in getting this bridge constructed," Heminger's statement said. "And I have no doubt that we will get through this one as well."

Indeed, defective rods are just the latest setback in the problem-plagued reconstruction of the Bay Bridge, originally scheduled to open in 2007. Last year, for example, a 19-ft section of concrete in an eastern-span tower foundation had not hardened before being tested by engineers."

http://enr.construction.com/infrastructure/transportation/2013/0328-Caltrans-Blames-Contaminated-Steel-for-Broken-Bay-Bridge-Rods.asp

Now it's been said that this is a common occurrence (hydrogen embrittlement), and it said they were checked in accordance with accepted practices....So in my mind unless the chief architect had included some special requirement that checking every bolt was required, then I don't see that anybody has responsibility, it was an accepted risk by the architect...now whether he/she was authorized to take this risk is another debate....$.02

This sounds like a nightmare to me.

There's the other small issue of: What happens when a 7.5 quake hits?

ormondotvos.....

Multiple NEW BOLTS failing in a structure ?? WE HAVE THE TECHNOLOGY ! This is NOT an EDGE of science problem.

Remove one....or a couple (this is a redundant structure...right ?) send it to a competent lab and you will have an answer within a week.

What is the ASTM Specification for manufacture ? Did the bolts meet this standard and was there proof ?

What kind of NDT was performed on the bolts before installation AND is this consistant with similar fasteners in similar installation ?

Most probably, we will come to one of three reasons for failure for new bolts:

- Failure in meeting bolting material/processing/galvanizing standards

- Improper installation

- Failure of coatings or coatings preparation

Engineering errors in design and overloading of bolts is a remote possibility.

Isn't Dyson a vacuum cleaner company ??

Vacuums... well, and toilets.