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Re: Field welding

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Joe,

I am curious...have you "educated" any of these contractors that don't
know how to tell what grade the bar is when you have encountered them (in
the field or meetings)?  In otherwords, kindly show/explain what the
markings on rebar indicate?

And, FWIW, I _RARELY_ ever offset single bars in masonry walls (if I have
a 12" wall I will might have offset bars due to two bars per cell) as the
odds of them being placed right is generally "iffy".  It is MUCH easier to
get a bar in the middle of the cell (much easier to "visually" see than
than say 3" in from one side...the latter requires them to pull out the
tape measure, heaven forbid).  More than likely, it is "overkill" on my
part as most masons in my area will do it right, but it only takes one to
not do it right.  I look at it as "wise" things to do to prevent possible
"stupid" mistakes in the field (kind of like keeping all bolt sizes the
same or if two different grades of bolts need to be used, have one be all
3/4" and the other be all 1", etc).

Regards,

Scott
Adrian, MI


On Sat, 10 Sep 2005, Joseph  Grill wrote:

> Yea, I know, I've been in the "gray" area for 20 some years, it's just a bit
> darker shade of gray here.  I don't know if "principled" is the right word.
> I've adjusted design practices in some ways to accommodate the area and my
> sanity but still staying with sound engineering practices.  Such as doing
> masonry design using 2500 psi concrete strengths and grade 40 rebar.
> Getting the concrete strength isn't a real issue here but the reinforcing
> grade is.  I've been ask to do inspections on masonry walls where I ask for
> grade 60 and say grade 40 was already installed and doweled into footings
> that had been poured and started curing.  The contractors here don't have a
> clue how to tell the difference so my designs have gone to grade 40.  When I
> am ask why bar size and spacing are increasing I tell them why.  I don't
> think anyone has ever looked at that sort of thing around here.  Bar
> locations in masonry walls is another thing.  Inevitably, if a details calls
> for a 9" "d" in a 12" CMU wall the bars will be centered.  Once again, size
> and spacing are changing in my designs.  Sizes go up and spacing are closer.
> When ask I tell them why.  Other places I have worked over all these years
> has not been this way.  Attitudes towards SE's other places weren't all that
> great, but here it couldn't be worse.  I have found a good mason in the area
> though.  He stopped me on a jobsite one day and started asking questions.  I
> think my name has gone around town with masons since they are learning that
> I won't accept two wythes of 8" CMU stacked along side each other in lieu of
> a solid 16" thick wall.  That has cost a couple of masons some time.  Rebar
> placement has cost a general contractor and a mason some time and money.
> Anyway, when this guy ask the questions he was sharp enough to kind of
> understand my explanations.  Since basically he does good clean work, and
> wants to know the differences and why, and he demands that he place the
> dowels in the footing and not the laborers for the concrete crews he will
> get my recommendations and my business when my wife and I build our home in
> a year or so (we just bought the ground).
> Joe
> ----- Original Message -----
> From: "Scott Maxwell" <smaxwell(--nospam--at)engin.umich.edu>
> To: <seaint(--nospam--at)seaint.org>
> Sent: Saturday, September 10, 2005 9:00 AM
> Subject: Re: Field welding
>
>
> > Joe,
> >
> > Welcome to the wonderful world of "gray".  Principled things like firing
> > clients, tearing out and replacing, etc are all nice and dandy in theory.
> > But, they can potentially put a serious damper on the ability to put food
> > on the table at times, especially in certain areas.  That is the joy of
> > our business.  How "principled" one chooses to be becomes a function to
> > some degree of how busy one is and how busy one want's to stay.  It is
> > real easy to fire a client if you have tons of clients beating down your
> > door...much tougher if the work load is a little "slow".  Ah, the joy of
> > business decisions...
> >
> > I suppose there is always the minimum wage job at McDonalds (hey, free
> > food though right?) or Walmart.
> >
> > :-)
> >
> > Scott
> > Adrian, MI
> >
> >
> > On Sat, 10 Sep 2005, Joseph  Grill wrote:
> >
> >> Gary,
> >> I don't doubt you.  I also understand that is common practice in parts of
> >> the US also to have the fabricators design the connections.  I have never
> >> lived in those areas though.  I will also say that when I'm fairly
> >> certain
> >> that I will get good shop welding or for that matter good field welding,
> >> I
> >> use full allowable stresses in the weld design.  I'll try to explain my
> >> point a little better.
> >>
> >> I have lived in this area of the desert SW for almost two years now.
> >> Before
> >> moving to this area I worked in areas of the country that kept up with
> >> construction practices, design practices, yes and even attitudes etc.,
> >> and
> >> some areas that I thought were behind the times, but this particular area
> >> really is really back there. It's a whole different scene and a whole
> >> different attitude.  I make good money and my wife makes better money and
> >> we
> >> love the climate and many other things about the area and wish to stay.
> >> Our
> >> company has discussed getting out of structural design entirely due to
> >> the
> >> practices and attitudes towards the structural engineer and the fees
> >> clients
> >> are willing to pay for structural engineering.  I would say the building
> >> department is trying to change in regards to structural requirements, but
> >> that change is coming slow.  I may have to gradually move into some site
> >> civil and on-site waste water management, to remain employed in the area.
> >> Those on the list that advocate things such as demanding mistakes by the
> >> contractor be immediately removed and replaced, demanding continuous
> >> on-site
> >> inspections, etc. must be working in an area where there is a bottomless
> >> bucket full of clients, 'cause it ain't that way here.  P*** off a couple
> >> of
> >> the architects and contractors in the area, and you are out of business.
> >> So
> >> we try to work with them, try to gradually train them and gradually
> >> change
> >> some attitudes.  That includes contractors, "designers", architects, and
> >> building departments, realtors and owners.  It is very slow going and we
> >> may
> >> or may not get there.
> >>
> >> Back to the original welding discussion.  I know requiring certification
> >> is
> >> common practice, and was so in all other places that I have worked, but
> >> practice and reality is not always the same in some locations.  I
> >> recognize
> >> that and take that in to account in some designs.  If that means using
> >> 50%,
> >> 60%, 70% or full stresses in weld design or any other materials.  You
> >> LRFD
> >> designers can understand it as a lowering of the phi factor that takes in
> >> to
> >> account materials and workmanship.
> >>
> >> I understand "take it out and replace it", I understand firing clients,
> >> demanding inspections etc., etc.  I have been there for all those things,
> >> but that ain't the way it is everywhere all the time.  Sometimes
> >> adjustments
> >> have to be made.
> >>
> >> Joe
> >>
> >>
> >> ----- Original Message -----
> >> From: "Gary Hodgson & Associates" <ghodgson(--nospam--at)bellnet.ca>
> >> To: <seaint(--nospam--at)seaint.org>
> >> Sent: Saturday, September 10, 2005 5:41 AM
> >> Subject: RE: Field welding
> >>
> >>
> >> > Joe,
> >> > It is quite common in Canada to ask the fabricator to choose the
> >> > connections and have his engineer stamp the drawings for adequacy of
> >> > connections. The set-up in Can with regard to welding is different
> >> > than the US as every company engaged in welding of structural steel
> >> > for structures must be certifed by the Can Welding Bureau and must
> >> > hire or retain a professional engineer who will take responsibility
> >> > for welding engineering.
> >> > Gary
> >> >
> >> >
> >> > On 9 Sep 2005 at 10:33, Joe Grill wrote:
> >> >
> >> >> I hadn't jumped in on this thread yet.  I'm curious as to why the
> >> >> engineer would even mention what he used as allowable stresses on the
> >> >> welds unless he was leaving the connection designs up to the
> >> >> fabricator.  That being said I think Jordan has covered the issue as
> >> >> far as I'm concerned.  I practice in an area where you never know who
> >> >> might be doing the welding in the field.  I can spec. anything as far
> >> >> as certifications etc etc. and will never know, because beyond the
> >> >> design I may have nothing more to do with the project. This area is
> >> >> like doing design in a third world country.  I've seen too many
> >> >> instances where grade 60 reinforcing is called for and grade 40 is
> >> >> placed. I don't think anyone in the area knows how to tell the
> >> >> difference in the field.  I could go on and on.  Anyway, since I have
> >> >> moved here I will now use a reduced stress on field welds; I will
> >> >> design with 2500 psi concrete and grade 40 reinforcing because what I
> >> >> have seen in the field.  Building inspectors have not been any help,
> >> >> and the "designers" and architects don't seem to care.  Like the other
> >> >> recent thread, the problems generally come back to the engineer to
> >> >> correct.  There wouldn't be too many "take it out and replace it"
> >> >> instances before I would be totally out of work.
> >> >>
> >> >>
> >> >>
> >> >> Joe
> >> >>
> >> >>
> >> >>
> >> >> Joseph R. Grill, P.E. (Structural)
> >> >>
> >> >> Shephard - Wesnitzer, Inc.
> >> >>
> >> >> Civil Engineering and Surveying
> >> >>
> >> >> 1146 W. Hwy 89A Suite B
> >> >>
> >> >> Sedona, AZ  86340
> >> >>
> >> >> PHONE (928) 282-1061
> >> >>
> >> >> FAX (928) 282-2058
> >> >>
> >> >> jgrill(--nospam--at)swiaz.com
> >> >>
> >> >>
> >> >>
> >> >>  <http://inet/index.htm>
> >> >>
> >> >> -----Original Message-----
> >> >> From: Jordan Truesdell, PE [mailto:seaint1(--nospam--at)truesdellengineering.com]
> >> >> Sent: Friday, September 09, 2005 10:10 AM To: seaint(--nospam--at)seaint.org
> >> >> Subject: Re: Field welding
> >> >>
> >> >>
> >> >>
> >> >> I don't think it has anything to do with the pledge.  In the case of
> >> >> field welding in education projects, it could be a "prayer in school"
> >> >> issue, depending on who's doing the welding. ;-)
> >> >>
> >> >> gskwy(--nospam--at)aol.com wrote:
> >> >>
> >> >> I have obviously not been following this thread closely enough since I
> >> >> can't quite figure out the connection between field welding and United
> >> >> State Court of Appeals for the Ninth Cuircuit,  but if anyone needs
> >> >> the court web site, here it is:  http://www.ca9.uscourts.gov/
> >> >>
> >> >>
> >> >>
> >> >> If I had to guess, I would say the connection may somehow have
> >> >> something to do with the Pledge of Allegiance, which in and of itself
> >> >> does not seem to be strongly connected to field welding.
> >> >>
> >> >>
> >> >>
> >> >> Gail Kelley
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> -----Original Message-----
> >> >> From: Bill Polhemus  <mailto:bill(--nospam--at)polhemus.cc> <bill(--nospam--at)polhemus.cc> To:
> >> >> seaint(--nospam--at)seaint.org Sent: Fri, 09 Sep 2005 07:43:32 -0500 Subject: Re:
> >> >> Field welding
> >> >>
> >> >>
> >> >> I realize that there are code provisions that may be questionable as
> >> >> to their wisdom in the fulness of time, but that's true of virtually
> >> >> any human endeavor.
> >> >>
> >> >> Certainly they are less arbitrary than many--if not most--of the
> >> >> decisions handed down by the U.S. Ninth Circuit.
> >> >>
> >> >>
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