I don't see any benefit to importing if all you can convert are lines. SAP2000 is a good drafting program for frame elements. What they really need is the capability to import 3D models. Once again there is no documentation on this topic. Thanks for your help Sukocek. If you know how to...
The AISC paper by Shankar Nair is obviously biased as he chaired the Task committee who wrote this mess. The Direct Analysis Method is anything but "direct". This committee took a simple method used in building codes all over the world and mucked it up. The notional load method is used in...
Is there any good info or informed opinions out there regarding uplift pressure on solar panel arrays? I'm reviewing a large project where overturning stability is an issue and time is short. I'd really appreciate some help trying to judge the appropriate uplift pressure that was calculated...
I'm actually a reviewer, not the designer. I raised the uplift/overturning issue at my first look at 90% design. They came back with very minor improvements for the 100% P&S and now they want to start construction. The designer seems to be trying to "beat" the code rather than "meet" the code...
A little more detail:
The local jurisdiction (UBC) requires 80mph Exposure C. The panels extend along the entire side of the embankment, which is 40 feet from the top to the bottom. The array is 500 feet laterally along the embankment. Its a large project. The design utilizes grade beams for...
I'd like to get some opinions on what wind load values are appropriate for an unusual structure - a large array of solar panels mounted on the side of an embankment. The panels are mounted on a lightweight steel frame, 4 feet off the embankment. With 4 ft of clearance under all the panels...
For a sign with this depth footing, I would expect the critical loads to be lateral due to wind. You might consider dropping in a spiral cage or WWF for good measure, depending on the the size of the W section and soil.
You don't say how tall the floodwall is, so its hard to give a judgement or check this, but if your net moment is overturning, as you describe, then your structure is unstable. End of story. Check loads and/or Redesign.
You should have a net restoring moment and the issue should be whether or...
Typo in my post (paragraph 3): I meant to write 2% - 10% of the APPLIED AXIAL LOAD. Not Pu. The amount of "notional load" to add in as a lateral force is based on a percentage of the amount of axial load.
You should be careful letting SAP2000 assign K-factors for you. Try this little experiment: Analyze a small frame with moment connections and at least one hinged connection. For the hinged connection, try releasing the moment in the beam, and then rerun it with the moment released in the...
Is there ANY OSB on this exterior wall? Even prescriptive codes often require a minimum length of OSB at the ends of exterior walls. Since this was engineered, I would assume that some portion(s) of this wall was designed as a shear wall segment. If that's not the case, and the entire wall is...
I deal with concrete tensile strength for mass concrete dams all the time. A good reference on this subject is by Jerome Raphael, PhD Berkeley. But mass concrete, footings and slabs are different than flexural members.
I agree with the ZERO Tolerence crowd here. I can't imagine a case where...
Check Structural Engineer Magazine Nov 2004 pg 24 (not to be confused with "Structures" magazine by ASCE) for a very nice article by Gregory Deierlein, PhD, PE. They are now calling this method "The Direct Analysis Method." This method will be introduced (to US codes) in the 2005 AISC Spec for...
Another consideration: You can't assume that the sill plate will be one continuous member. The shear at the sill will not transfer (drag) across a splice unless there is a shear panel bridging it at the splice.
I use the unit shear to calc AB spacing, which is based on the length of shear...
And to avoid splitting 2x's when nailed from both sides, especially the boundary members. You'd never even see it with ply on both sides. Good practice to go 3x's for this case, even if it weren't in the code.
If you are just trying to avoid rebar (probably for dowels), then the cheaper models usually get the job done. The high-end models are necessary if you want to determine the size and/or depth of the bars.
I'd hire a company if you need to size the rebar, and I'd buy a cheapo if you're just...
Your question forced me to read through my Steel-Framed Open-Deck Parking Structure Design Guide (AISC). I've never done a parking structure, but if I did, it would probably be concrete. There's some good info in this manual, especially regarding prestressed decks.
Anyway, they recommend an...
Guess you'd have to call that "drive live." I couldn't resist that one.
It would seem prudent to check for an impact load. I have a design guide for steel parking structures at home. I'll check it and get back to you. Seems to me that steel columns would be more vulnerable than concrete.
May I suggest that you let your lawyer be the scapegoat. "I'd sure love to fork over my hard work for nothing, but gosh, Mr. Developer, my lawyer just won't let me. Liability, or something like that, I don't understand all that legal-sleeze stuff, but he just won't let me give you my...
The 2001 CBC is based on the 97 UBC, not the IBC. Perhaps the shear table and footnotes are the same in the IBC and UBC.
FYI
The next generation of California building codes is up in the air. The Building Standards Commission picked the NFPA5000 instead of the IBC, but there has been a large...
