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Bay Bridge Broken Bolts

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What is the inside information on the Bay Bridge bolts?

What I have been able to learn is that:

The bolts specified were ASTM A354 BD, hot dipped galvanized.
30% of the bolts manufactured in 2010 fractured during the tensioning 
operation. The fractures were attributed to hydrogen embrittlement.
There are procedures to investigate and mitigate for hydrogen 
embrittlement.  It is unknown if these were specified. The ASTM A 354 
cautions about hydrogen embrittlement for galvanizing the BD bolt.

Several entities have chosen to use high strength molibdenum bolts to avoid 
 galvanizing and obtain corrosion resistance.

I am just kicking this out for discussion.

Regards, Harold Sprague

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