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Re: Analysis Standards - Nomenclature?

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Bruce,

 I  did a 3D analysis of my commercial sign structure using a friend's
 STAAD III. The results were almost the same as my plane frame analysis
using RISA2d. What I did was Draw the geometry of the tower only and put the
oppositely directed forces causing the torsion on the tower.

May I request your comments. Using RISA3D, would the results be the same?

Thanks in advance.

Alex C. Nacionales, C.E.
-----Original Message-----
From: BRBATES(--nospam--at)aol.com <BRBATES(--nospam--at)aol.com>
To: seaoc(--nospam--at)seaoc.org <seaoc(--nospam--at)seaoc.org>
Date: Sunday, June 28, 1998 8:57 PM
Subject: Re: Analysis Standards - Nomenclature?


>
><<
><< Bruce, in RISA3D , can we model a simple or very complicated wood framed
><<house in 3D?
>
>Hey, RISA-3D can do anything! ;-)
>
>
><< For example:
><<
><< 1. Plywood shtg is a horiz plate where we apply uniform vertical DL and
LL
><< and horizontal wind load
><< 2. The plates distribute the loads to rafters, joists and studs.
><< 3. The reactions from rafters, joist and studs are transfered to
><< headers,beams, and girders.
><< 4. The reactions from headers, beams and girders goes to posts/columns,
dbl
><< studs, trimmers, etc.
><< 5. The reactions from posts etc. and walls becomes oint and uniform load
to
><< design the lower level joists, beams, etc
>
><< In other words, if each and every member of a wood framed house is
inputed
>as
> <<structural members on RISA3D and we apply uniform vertical and
horizontal
> <<loads on the plywood roof and floor and wind load on wall shtg(seismic
>loads
> <<can be applied as a percentage of the DL applied horizontally), will all
>loads
> <<or combination of loads be applied to appropriate structural members?
>
>Yes, this would work in RISA-3D (as well as in a number of other programs).
>
><< Can we simplify the series of joist or studs as a single member to save
on
> <<inputing time? (we only input a single joist or stud at the critical
span)
>
>Yes, and I would highly recommend this if you aren't actually sizing the
>components of the joist itself, etc.
>
><< Can we get the size of any member we choose? (not all since we dont need
><<calcs for all rafters/jsts, beams, studs and column but only the critical
>ones).
><< Can we get printout of calcs for selected members only showing span,
loads,
><< end reactions, bending moments, etc.?
>
>Yes you can do all this.
>
><< Maybe, the other expensive programs used for big steel buildings can do
all
>or
><< most of these analyses right now but small offices doing wood framed
houses
><< for small fees cannot afford them.
>
> << Ernie Natividad
>
> RISA-3D, as well as SAP2000, StaadIII, ROBOT, etc. is a general purpose
>program that can handle everything you've described, though if you are ONLY
>going to be doing wood structures, you should probably take a look at some
of
>the wood-specific programs as well, such as WoodWorks, QLAT, etc. (I'm not
>really that familiar with them so I can't offer an opinion as to their
>usability.
>
>Bruce Bates
>RISA Technologies
>
>
>