Bay bridge

Date 01-05-2010 13:21

Key statements in that article:
"Iwasaki said Caltrans still doesn't know, some six weeks later. It may have to do with greater than expected vibrations, he speculated.

Adams expressed concern about how long it's taking to get answers.

Iwasaki said pieces of the failed metal parts – the original cracked eyebar, and the snapped tie rod that was part of the repair holding the cracked eyebar in place – were recovered as quickly as possible and sent to a forensic metallurgist in Santa Fe Springs. That forensic report is due in a few weeks.

The metallurgist, McKnight Laboratory Inc., will help Caltrans understand whether metal failed after cracks appeared on its exterior or after inside cracks spread to the exterior of the part, Iwasaki said.

"After that, we'll make sure our inspections are better and safer," Iwasaki said."

Reading between the lines, two suspects emerge: resonance and or poor initial inspection. I'd put money on both.

By 3.2 Inspector (***)

Date 01-05-2010 13:27

I agree... Just wondered if you guys had heard anything new.

"After that, we'll make sure our inspections are better and safer," Iwasaki said." <---- this points in that direction :)

3.2

By welderbrent (*****)

Date 01-05-2010 14:15 Edited 01-05-2010 14:19

I think they are 'starting' in the wrong place. I would say 'after that we need to make sure our welding is better and safer'. Sounds like where the additional training needs to start. The inspections just backs up the accomplishment of the new and better procedures and the training and skills of the personnel.

Thought I'd better come back and explain. The original construction may have been to proper procedures at the time. Any repairs done since may have needed better oversight. The welders themselves may not have been the ones 'responsible'. But, any correction to avoid future problems needs to get down to the first tier to be sure it doesn't happen again. THEN, the inspectors need to have a better understanding of what they are watching for before, during, and after the welds are put in place and when doing annual inspections to see how things are holding up.

Have a Great Day, Brent

By Nanjing Date 01-05-2010 14:44

Can I ask a simple question? Have any of you guys been involved in a failure investigation?

Ascertain the route cause of failure.

Determine and develop preventive measures of future possible similar failures.

Develop Quality Procedures to ensure preventive measures have been implemented.

By 3.2 Inspector (***)

Date 01-05-2010 14:52

Can I ask a simple question? Have any of you guys been involved in a failure investigation? <---- Yes :)

Ascertain the route cause of failure. <----- Yes :)

Determine and develop preventive measures of future possible similar failures. <---- Yes :)

Develop Quality Procedures to ensure preventive measures have been implemented. <---- Yes :)

3.2

Will you be a serious competitor to the EXCLUSIVE rights to have the signature, which I now have? :)

By Nanjing Date 01-06-2010 12:58

By Nanjing Date 01-06-2010 13:13

"That forensic report is due in a few weeks".

Are they serious? A few weeks????

Stinks!

By rfieldbuilds (**)

Date 01-05-2010 14:55

To the best of my knowledge, the eyebolt was a casting rather than a weldament. From what I've seen in the local papers, this "repair" had more to bo with the support running from the bottom of the bolt to the bridge deck. The failure was above the original repair. The San Francisco Chronicle, Oakland Tribune, San Jose Mercury, Marin IJ and Press Democrat all had extensive coverage during this fiasco...

By jrw159

Date 01-05-2010 15:11

http://wjmg.com/index.htm

jrw159 :-)

By Metarinka (****)

Date 01-07-2010 22:25

yes, yes and yes

Failure analysis is a rather common task for a welding engineer.

luckily In my report I found that it wasn't my fault.