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RE: Bay Bridge Broken Bolts

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My experience with DOTs is that they are notoriously hide-bound, owing to:

- The naturally political nature of their organizations, such that a small 
group or even a single individual with "juice" can effect policy that may 
not reflect the consensus of engineering and construction practice.

- The large amounts of money they are obliged to spend on basic research, 
given to the state U's at the behest of elected officials. Certain of that 
research may yield "data points" that could be seen as outliers under 
normal circumstances, but the "WAS invented here" syndrome takes precedence 
 over scientific sense.

EXAMPLES:

- At a certain large state DOT of my certain knowledge, the geotechnical 
"engineer" for the state was not an engineer at all, but a "geo-scientist" 
who scoffed at accepted geotechnical engineering practice. This person 
insisted that all one needed to determine the competency of any soil, 
anywhere, to support any structure, was a Dutch cone penetrometer test at 
intervals in the soil bore. All other data, in his view, were irrelevant 
alongside this. He had spent a number of his department's manhours 
developing an in-house software program to determine drilled shaft 
foundation capacities on this basis, and the insistence by the geotechnical 
 engineering professional community that this was not sufficient, nor did 
it reflect the standard of care in engineering for construction anywhere 
else in the world, fell on deaf ears. "Yeah, they'd love to sell us all 
these services..." was the response.

Pointing out the number of repairs to foundations some years after 
installation did no good. That was a "maintenance issue" (and maintenance 
and construction inhabit completely different universes, walled off one 
from another by a black-hole such that no information ever passes between).

- For many years, the Texas Department of Transportation would not allow 
pozzolanic admixtures in its concrete, for any purpose or reason. None. 
What. Soever. As far as I'm able to determine, this proscription originated 
 with a single research study at Texas Tech or Texas A&M, that showed 
"performance problems" with concrete that included pozzolans. I'm not 
certain of the content or any details of that study, I was told this was 
the reason.

At any rate, this went on for many years, until finally one young bridge 
engineer herself headed up a program of research into so-called 
"high-performance concrete" that was underpinned by several grants to the 
state university systems over a period of years. One of the findings of the 
 studies was the efficacy of pozzolanic admixtures in production of HPC - 
she was too young to understand the anti-pozzolan culture that had gone 
before. She was being groomed for greater things in the department, and so 
was not reined in.

Almost overnight, the prohibition on pozzolans disappeared.

-----Original Message-----
From: seaint-seaosc(--nospam--at)mail-list.com [mailto:seaint-seaosc(--nospam--at)mail-list.com] On 
Behalf Of Gary L. Hodgson and Assoc. Sent: Tuesday, May 14, 2013 6:36 AM
To: seaint-seaosc(--nospam--at)mail-list.com
Subject: Re: [SEAINT-SEAOSC] Bay Bridge Broken Bolts

The NYTA was known for being very conservative. In 1976, they wanted to 
know why we were using bolts in lieu of rivets. We had to persuade them to 
allow A325 bolts on that particular job. Gary

On 2013/05/13 11:31 PM, Harold Sprague wrote:
> That is a bit odd.  If the A 490 bolts are tensioned per the RCSC, the
> stress remains static until you exceed the tensioning force.  That
> should never happen.  If the issue is hot dipped galvanized, I don't
> blame them for not allowing them.  Hydrogen embrittlement is not well 
> understood. 
> Regards, Harold Sprague
> 
>> Date: Mon, 13 May 2013 08:02:14 -0400
>> From: design(--nospam--at)hodgsoneng.ca
>> Subject: Re: [SEAINT-SEAOSC] Bay Bridge Broken Bolts
>> To: seaint-seaosc(--nospam--at)mail-list.com
>> 
>> Back in the 1970's, we were supplying steel to the New York Transit
>> Authority and they would not allow A490 bolts in any dynamically
>> loaded structures. This occurred again in the 1980's on a bridge for

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