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This is the response from Mike Engestrom of Nucor to Mark Gilligan's
post:
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In a message dated 11/5/98 9:42:45 AM Eastern Standard Time,
hhuang(--nospam--at)co.la.ca.us writes:

<< One option if you want a higher strength steel for the columns is ASTM A913
which is availible from Trade Arbed.  This steel is availible with a yield
stress of 65 ksi and good toughness values.  The only problem is that it is
typically only availible in W14 sections although Trade Arbed has been willing
to roll other sections.  The price has also been competative.  It is my
understanding that at least one of the American mills (very possibly Nucor)
has the technology to make this steel but has chosen not to.   For those who
are concerned about availibility of steel from a foreign mill, I would suggest
you look at the mill reports from you latest steel project.  You will probably
find steel produced by mills all over the world.  It is my observation that
the market for steel is an international market with firms like British Steel
and Trade Arbed very competative in South East Asia which is halfway around
the world from their mills.  A key reason why our options are more limited is
that the structural steel market is a small part of the overall steel market
and the US mills have not felt the pressure to be responsive to the needs of
the engineering community.  Mark Gilligan >>

Henry,

This is in response to the message you forwarded to me from Mark Gilligan.  He
is correct that the sole producer of ASTM A913 Grade 65 in the world is
Luxembourg-based TradeARBED.  He is also correct in that Nucor-Yamato Steel
(NYS) has the technology available to produce the QST (quenched & self-
tempered) wide flange structural shape product to attain a Grade 65, however,
NYS has chosen not to move into this technology at this time.  For NYS to
implement the QST technology into production would involve a major capital
investment of $15+ million.  In recent years the structural steel industry has
been moving toward a new base grade (Grade 50 in lieu of Grade 36) and has
been promoting a single-grade (Grade 50) design versus using two grades,
Grades 36 & 50.  There are many inherent advantages from production to
construction in using a single grade.  The market potential for Grade 65 is
tiny in comparison to the current grades of structural steel and it is
believed that rational designs can be developed using a single grade (Grade
50).  The primary place where Grade 65 is perceived to be an advantage is the
west coast.  ASTM A913 Grade 65 is a product that is quenched and self-
tempered, in essence, a case-hardened product, that still has some technical
issues yet to be resolved, especially on the larger, heavier section sizes.
It is hoped that current and future research may resolve these issues.  Until
the issues are resolved and the market potential is better identified, NYS
does not plan to install the necessary equipment to produce ASTM A913 Grade
65.  

Again, the industry is moving toward Grade 50 as the base grade for building
structures.  In fact, in May 1998, ASTM approved an "enhanced" version of ASTM
A572 Grade 50.  We believe this newly approved ASTM grade will be designated
ASTM A992, however, it has not been officially announced by ASTM.  The
"enhanced ASTM A572 Grade 50" is in accordance with the AISC Technical
Bulletin # 3 (March 97) and has been produced by domestic structural steel
mills, including Nucor-Yamato Steel, for the past two years.  Virtually all of
the ASTM A572 Grade 50 produced by NYS meets the new criteria established for
the new Grade 50.  The AISC TB # 3 can be viewed on the AISC web site.  This
new Grade 50 is an attempt to eliminate the confusion regarding the "dual-
graded/multi-certified" "A36/A572-50" steel grade issue.  It is believed by
many that moving to a grade higher than Grade 50 in designs (i.e., Grade 65)
would be unproductive and simply add more confusion or unnecessary complexity
to design.  

It has been noted that many west coast designs tend to have fewer frames that
provide lateral load resistance, and fewer columns creating the need for
"jumbo" columns in low-rise structures.  Since Northridge, the industry has
called for additional redundancy (load paths) in designs.  This should provide
a structure with more lateral load resisting frames, smaller axial loads
(smaller columns), thereby reducing the need for a Grade 65, avoiding any
availability issues.  

We are in an international marketplace, as Gilligan notes.  And right now,
based on the global economic crisis, the USA is the focal point for imported
structural steel.  The USA has a term for this, it's called "dumping", and the
newspapers are filled with the localized effects on our domestic general steel
industry.  

The structural steel industry has undergone some major changes in the last 10
to 15 years at significant capital expense.  During this time period, there
have been significant changes and enhancements to structural steel shapes
(i.e., better surface and internal qualities) which benefit the engineering
community compared to older structural steels.  One of the best enhancements
is the development and current production of the new Grade 50 (that we believe
will be designated ASTM A992 within the next few months).  The structural
shape industry has been very responsive to the needs of the end user.  Besides
providing the enhanced material that's readily available, the cost of
structural steel is still a great buy.  The structural steel industry believes
the best structure is one that is of high quality, dependable, and is low in
cost and the shape producers believe they are doing their part to make that
happen.  This is in the best interest of not only the engineering community
but also the building owner.  

Slightly different from traditional "building" structures, the qualities and
efficiencies of using large deep beams (e.g., W40 sections) for short-span
bridge applications have proven to be readily available, very cost effective
and competitive against precast concrete.  Over the past 25-30 years, the
short span bridge industry was considered lost to "concrete", and only within
the past 5 years or so, it's been proven that "steel" can make a comeback.  

So, again, the structural steel industry has been quite responsive to the
needs of the industry.  

Mike Engestrom
Technical Marketing Director
Nucor-Yamato Steel
(301) 694-3067
(301) 694-2349 FAX


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