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Bay Bridge tower rod is fractured, Caltrans says

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     Bay Bridge tower rod is fractured, Caltrans says

<http://cirrus.mail-list.com/seaint-seaosc/82998822.html>

The Comments at the bottom of the story are showing the public anger
against (Caltrans) engineers even in many cases asking for jail term for
the Chief Engineer of the bridge Dr. Brian Maroney.

FYI, the "rod" in this news story is one of the 400+. 3-inch diameter
anchor rods connecting the single tower of the Self Anchored Bay Bridge to
the composite (steel box filled with unreinforced concrete) pile cap. The
rods are about 25 feet long have threads and nuts on both ends. The nuts at
the top connect the rods to the base plate and the nuts at the bottom
connect the rods to a steel grillage at the bottom of composite pile cap .
The grillage is embedded in the concrete.

The rods are inside steel pipe sleeves. The space between the rods and
sleeves had to be field with grout but the contractor has not placed the
grout and Caltrans , in charge of inspection and Inspection and quality
assurance has either not inspected the sleeves or has approved them without
grout.

The rods are A354 BD high strength rods (150-160 ksi ultimate strength)
which all bridge codes including AASHTO and Caltran states that should not
be "hot-dip" galvanized. It has been known for decades that when high
strength steel is hot-dip galvanized , it becomes hydrogen embrittlement
and over time develops cracks, especially if exposed to humidity and
corrodes.  In this case these rods were under the rail , unprotected, for
years and then inside salt water accumulated inside the sleeves.

During high wind and especially earthquakes these rods are needed to
prevent the tower from toppling.
Caltrans so far has pulled out three rods and the other 2  have cracks and
this one discussed in the story is fractured.

<http://cirrus.mail-list.com/seaint-seaosc/70409691.html>

--

 Abolhassan ASTANEH-ASL, Ph.D., P.E., Professor
2013 Minner Faculty Fellow in Engineering Ethics and Social/Professional
 Responsibility and
2013-14 U.S. Fulbright Senior Research Scholar
Department of Civil and Environmental Engineering
781 Davis Hall,  MC 1710
University of California,
Berkeley,  CA 94720-1710, USA
Web: www.ce.berkeley.edu/~astaneh
Web: www.astaneh.net
Phone; (510) 642-4528

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