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Sun Dec 8, 2013, 12:27 PM

 

Experts raise new doubts about essential Bay Bridge rods

Yun Chung, a retired engineer and metallurgist, read the official report explaining why massive, high-strength steel rods on the new San Francisco-Oakland Bay Bridge broke last March and was stunned – then alarmed.

At first glance, Chung said about the July report, he saw obvious errors – some typographical, others that confused basic terminology. Digging deeper, he discovered more important problems. He concluded that the analysis defied metallurgical science and common sense.

“I think it’s very shameful that in this public document, this important (oversight) report, there are so many errors. (I have) a sense of outrage,” Chung said in an interview last week.

Diverting attention from caring for his disabled wife, Chung, 81, said he spent hundreds of hours reviewing the report, consulting the technical literature and writing – with another engineer – a 105-page rebuttal. Chung, who had worked for Bechtel Corp., and Lisa K. Thomas, a materials engineer at Berkeley Research Company, a consulting and test lab, recently prepared an 18-page supplement to the report after a request from The Sacramento Bee to further detail their concerns.

Read more here: http://www.sacbee.com/2013/12/08/5981376/experts-raise-new-doubts-about.html#storylink=cpy


http://www.sacbee.com/2013/12/08/5981376/experts-raise-new-doubts-about.html

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Reply Experts raise new doubts about essential Bay Bridge rods (Original post)
Bennyboy Dec 2013 OP
arcane1 Dec 2013 #1
JimDandy Dec 2013 #2
Egalitarian Thug Dec 2013 #3
Bennyboy Dec 2013 #4

Response to Bennyboy (Original post)

Sun Dec 8, 2013, 12:49 PM

1. I'm starting to feel glad that I don't have a car!

 

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Response to Bennyboy (Original post)

Sun Dec 8, 2013, 01:31 PM

2. Failure of the anchor rods will bring down the whole bridge

according to Chung.

The original oversight review concluded that the giant rods became brittle when hydrogen entered them during the manufacturing process. The problem was then exacerbated when construction was delayed for five years because the bolts were exposed to water off and on during the delay.

Chung has a more obvious conclusion: that the hydrogen was introduced when the bottom of the rods, where all 32 breaks occurred, were corroded by the standing water. That was the primary reason they snapped when tightened.

The rods on the eastern side are now encased in watertight chambers that are dehumidified, according to the oversight report. Chung asserts that, due to the marine environment, the chambers must be airtight to stop hydrogen atoms from being introduced to the steel anchor rods. Prominent experts who have read his report agree that Chung's assessment is correct and his proposed safety measures are necessary to prevent future corrosion

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Response to Bennyboy (Original post)

Sun Dec 8, 2013, 02:57 PM

3. Incompetence and/or corruption in a public works project? I'm shocked. n/t

 

& R

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Response to Bennyboy (Original post)

Sun Dec 8, 2013, 03:31 PM

4. I had a friend, a CALTRANS engineer, who worked on

 

The Bay Bridge, the Embarcadero Freeway and the Cypress structure in Oakland. We went ot many events in the Bay Area together and when we traveled over the bridges and such he would tell us all about it.
In regards to the Cypress Structure, The overhead freeway in Oakland that collapsed in the Loma Prieta quake, that the reason that it drove like a boat was because it had "the wrong mud jacks". It was seriously like riding waves and stretched from the Bay Bridge to past downtown. He told the story about how contractor used the wrong mud jacks and that it got passed off because of expediency. (Sound familiar?)

He said the same thing about the Embarcadero freeway as well, but it did not rock like the Cypress did. It too was heavily damaged in the quake.

He never mentioned the bridge that was damaged but he did have some interesting stories about the designer of the bridge and how he did not like to see off bridges, so he made the rails solid and too high too see off of.

he died before the Loma Prieta quake. Preach Perry was his name. Whenever I go those areas I think of him and the people that died because a private contractor screwed the people over and, in the name of expediency, a decision was made to ignore questions......

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