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RE: OSHA 4-bolt column anchorage

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Harold

No disagreement that there was and still is a real
problem.  The ultimate problem is that we do not value
the life of an iron-worker enough.

You are right that as the engineer of record for the
project I do not want to get involved in means and
methods safety issues.  On the other hand if I were
hired directly by the erector my attitude changes
significantly.  While I would be cautious I see no
problem with getting involved with means and methods
issues and if advised by a safety expert would assist
with safety issues.  In a sense this is no different
from an in-house engineer at a major
fabricator-erector.

The problem is apparently that the erection industry
wants a magic bullet and is not willing to hire the
necessary experts.  The reality is that the current
regulations have a flaw and I as the engineer for the
Owner of the project cannot solve it.  The solution
must come from the steel industry.

Sincerely
Mark Gilligan



from Harold Sprague
++++++++++++++++++++++++++++++++++++++++++++++++++
Mark,

I did not participate on the development of the OSHA
Subpart R, but I am personally acquainted with some of
the participants and I know some of the reasons for
the provisions. Following is the section on Erection
Stability which contains the 4 anchor rod provision
(AISC PC version of anchor bolt;>). I have included my
comments. By the way the OSHA web site links to
official inquiries and interpretations. 
http://www.osha.gov/pls/oshaweb/owastand.display_standard_group?p_toc_level=1&p_part_number=1926

Subpart R
General requirements for erection stability.
1926.755(a)(1)
All columns shall be anchored by a minimum of 4 anchor
rods (anchor bolts).
[This provision happened for 3 reasons.

First structural engineers were traditionally very
hesitant to participate in the development of erection
plans. It is that methods and means thing that drives
insurance carriers nuts. Secondly, iron workers were
getting killed and hurt due to column instability.
Thirdly, the iron workers needed a solution to the
problem of erection stability that did not require an
"engineered" solution. I understand that the 4 anchor
rod minimum is limiting to designers, but the iron
workers needed a solution TODAY and not a study for
the next several years. I had to do a presentation to
some iron workers shortly after a column stability
failure that caused death and injury to several of my
former colleagues (iron workers) and defend the lack
of action of my current colleagues (engineers). To say
that the iron workers were hostile is to put it
mildly. I understand their frustration, and I
understand the trepidation of engineers to design an
erection plan. This is the land of risk, liability,
and low reward. But it is the reality in which
buildings have to be constructed. The 4 bolt
requirement is not the answer to all iron worker
hazards, but it will have to do until structural
engineers get into the methods and means. ] 

1926.755(a)(2)

Each column anchor rod (anchor bolt) assembly,
including the column-to-base plate weld and the column
foundation, shall be designed to resist a minimum
eccentric gravity load of 300 pounds (136.2 kg)
located 18 inches (.46m) from the extreme outer face
of the column in each direction at the top of the
column shaft. [This is indeed to characterize an iron
worker tied off to the top of a column. This may or
may not be greater than a wind construction load ASCE
37-02. ] 


All of Subpart R was an issue that needed to be forced
for the safety of iron workers. If we structural
engineers don't like it, it is incumbent on us to
become involved in developing a solution. But if we
want to add a provision for structural engineers to
develop erection plans, we had better check with our
insurance carriers first. Frankly, those of involved
in EPC construction can't avoid the liability (as a
company), so I have no problem in developing erection
plans. But the general consulting industry may have
some barriers. 


I agree that Subpart R may provide a false sense of
security, and is not an ideal solution. But it is the
best that could be developed by those that saw a
problem and acted to effect a solution. 

If interested reference:
AISC Design Guide 10 - Erection Bracing
OSHA 1926 Subpart R
ASCE 37-02 Design Loads on Structures During
Construction
LPR Steel, Loveland, CO

Regards,
Harold Sprague





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