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RE: Analysis Standards - Nomenclature?

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Thanks for spending the time to explain your system Kasey. It is very
similar to the other comments I have had as well as the methods I use. I
like the idea of placing the level before the beam. This way it is easy to
sort members by level, then type, and so forth.
I substitute CAD overlays for your manual methods, but have not noted loads.
When working out the lateral, I break the structure into blocks based upon
my grid system. This way I can break the drawing into separate  blocks to
show which loads are transferred from each side of the diaphragm. If the
building is an "H" shape, for example, I break each vertical leg of the "H"
into three separate blocks and distribut load to the shearwalls at the
horizontal block of the "H". This way I proportion the shear uniformly by
stiffness of the diaphragm into each block. If I chose to drag shear into
the upper and lower block of the vertical side only, I will have a graphic
representation of this to sumit for plan check approval.  I also use the cad
to determine the actual areas of the blocks for lateral distribution.

We still need to discuss how to track loads and reactions. Have any of you
using either a spreadsheet or MathCad figured a standard to use where you
can tell which member the load applies or the reaction occurs from? I have
used a reaction method where I start with B0101 for Beam 1 Reaction 1. The
second beam first reaction starts with B0201. If the reaction from the beam
continues to the column, the column load to the next member (ftg or beam)
becomes C01B0201. Using Kasey's levels this might look like 02B0201 for
second level Beam 2 reaction 1.  This does not seem too confusing to follow.
Any other suggestions?

Thanks for the feedback.

Dennis Wish PE


-----Original Message-----
From:	K. Hemmatyar [mailto:kch(--nospam--at)ultranet.ca]
Sent:	Saturday, June 27, 1998 12:55 AM
To:	seaoc(--nospam--at)seaoc.org
Subject:	Analysis Standards - Nomenclature?

Dennis:

>>1. What types of standard's or tracking methods do others use?<<

Tacking loads: I copy each floor plan on a 11"x17"transparent sheet (I make
sure the drawings are dead on scale.)
Then starting from roof (second floor plan) once I complete the framing
(and/or roof truss) lay-out on the blue print (the same way Steve Privett
described numbered B, beams C columns,... viewed from bottom  and right so I
know "B-12 R" means right Reaction of B-12) then I lay the
11"x17"transparent sheet of the lower floor over the roof (second floor
plan.)

There I can see through transparent that which reaction is coming where. If
it is a 3 level building I can follow the point loads that are coming down
form two levels on a beam (or getting accumulated on the wall) and I
appropriately design the member.

At the mean time that on each level of my "Mark-up" plan I number the beams,
column, etc.. I also write any reaction larger than 3 kips and circle it.
This way I make sure as I go to the lower level I transfer this load. At the
foundation level I generally have 3 to 4 types of single footing pads.

On my foundation plan I  show a simple foundation schedule :

Footing      Size                       Reinforcing
F-24            24"x24x8"             2-15M rebar (or 2#4 USA) each way
Bot.
F-36            36"x36"x8"           3-15M
F-44            44"x44"x10"         4-15M

I use (1) Woodwork of Canadian Wood Council (2) our own in-house Spread
sheets  (3) and another popular software supplied by an American Wood
product supplier (I do not mention the name. There are at least 3 or 4 large
ones) for the design of  laminated beams other than Glulams.
When using their software if I do not use  their product and just want to
specify 2x  Built-up lumber beams I have a table that shows Moment and Shear
capacity. So I can compare the results  and specify the member. I also check
the Deflection by verifying the "ExI" product.

Since I am using these software I save each file. Therefore I have a
directory for year of "1998". Then I have sub-Dir. for each project (i.e.
"98026") then every time I have a revision (which happens here in Vancouver
9 out of 10!) I just create another sub-directory under "98026" call it
"june_26.98" which simply tell me the date I had revision. I also have a
sub-Dir. for "Options" and one for after framing Inspections "frm_insp."

Whenever I do a revision I use my latest structural drawing that I produced
last and use it for my "Mark-up."
This works out well whether I am using CAD or other means.
If for instance I am redesigning B-32 I just recall it modify the loading,
span,  etc. and save it in the new directory. I also keep hard copy of all
calcs. in file.

Regards
Kasey Hemmatyar, P. Eng. (structural)
Vancouver, B.C.
_______________________message separator_______________

Dennis wrote:

We have discussed establishing CAD standards in the past, but I don't think
that we have ever talked about uses standards in analysis. Many of us who
design large custom home are painfully aware how difficult it can become to
track reactions and to assure that all loads are applied to the proper
member. Large commercial and industrial structures, for the most part, are
rather symetrical and don't have the same level of difficulty as many of the
architectural designs found in wood framed projects. Therefore, it becomes
much more difficult to track members and loads from top to bottom.
I have tried various different ways to track members and loads in my
analysis package - the typical B?? for beams, RJ?? For Roof Joist, CJ -
ceiling joist, C?? for columns etc. In each case I still tend to lose my
load paths and spend a great deal of time tracking reactions that occur from
one member which are to be applied to another.
I also try to coordinate my member numbers on the plans so that it helps
simplify both the plan check cycle as well as later revisions.
1. What types of standard's or tracking methods do others use?
2. Do you use a spreadsheet while laying out loads? If so, do you have a
means to sort reactions so that you can track which member they are applied
to (other beams, headers, columns or foundations)?
3. Has anyone used a graphic program like Visio or Powerpoint to graphically
track loading conditions which are then pasted into an analysis program like
MathCad? What other sources are available to simplify setting up an analysis
model.
4. How do you establish your member nomenclature priority?
5. Do you use a standard  nomenlature to track reactions (ie, B01R01,2,3 -
Beam 01 Reaction 01, 02 and 03 for a two-span beam)?
6. How do you number revisions - especially if you need to change the
framing in one area of a large structure? This has happened where the
architect and owner wished to modify the view from a bedroom and decided to
remove a column (gravity and laterally loaded) to join the mitered glass
corner for an unobstructed view.

I would appreciate hearing from anyone interested so that we might find a
standard which would help us organize our design time better. If you know of
any commercial software that performs this function, please let me know.

Sincerely,
Dennis S. Wish PE