Steel design aid (AISC 360-22) - sharing the tool 2

[RattlinBog]

Over the last two years, I developed a steel beam-column design aid according to AISC 360-22 for my M.S. civil engineering non-thesis project. The design aid (built in Excel) can be used to analyze and design shapes with original, reduced/corroded, and reinforced/built-up section properties.

My intent is to share the tool publicly so other practicing structural engineers can use it. I was thinking of sharing it on steeltools.org. My grad advisor agrees with this plan.

This might be an odd question, but could there be any risks or unintended consequences I should be aware of before sharing a design tool for free, public use? I'm not too worried about it somehow coming back to bite me, but I suppose there's always the risk of someone misusing or modifying the tool and causing inaccuracies. Perhaps someone could also "steal" it, call it their own, and try to sell it. Seems unlikely but any thoughts?

 

[alt0]

You could consider password-protecting the editing of any formula based cells to cut down on misuse.

 

[lexpatrie]

I wouldn't be too concerned with the overall liability (not that I'm a laywer) but you could borrow language from the Tomanovich spreadsheets or the bay analysis tool AISC put out a few years ago (dozens).

Professional Engineers are responsible for their own work, after all, and the work (even if incorrect) of their subordinates under their direct supervision and/or responsible charge, if they use a spreadsheet they don't understand, or dont check the results for plausibility, that's on them (NIH has some justification in this field, after all) and there's perhaps a body of existing disputes between engineers and software suppliers, though I really doubt anything got past summary judgement. Any attempt to assign product liability to software is pretty difficult as far as I know.

The reality of most of these tools is they languish online and since they are all stand alone, they don't get too many downloads. The Tomanovich wind calculation spreadsheets are an exception, I see those a lot, particularly in forensics for whatever reason. But it only does 5 mile per hour increments so .. shrug. That's a different discussion...

If nobody shares, nobody can build on the existing body of knowledge. We already struggle to educate the newer engineers on lessons learned, incorporate new research and failure findings into "new work" (see Petroski), so it's worth doing. I feel like OpenSees is kind of the culmination of dozens of researchers over the years building on the code base. So maybe the open source has a chance.

 

[RattlinBog]

I'll likely protect the formulas but without a password to prevent accidental modifications but to still allow folks to update the spreadsheet intentionally when newer editions of AISC 360 come out.

I think the only small concern I had was somehow taking on risk/liability if someone were to use the design aid incorrectly, or if there was still a mistake in it that I didn't catch. Like you said lexpatrie, maybe I could add a cover sheet with some disclaimers. I'll be done with the project and my report in the next month, so I'll plan to think about that as I finish up.

I'm not expecting a lot of usage of the sheet, but even if it helps a dozen engineers, it'll be worth it! I'll certainly continue to use it in my career. The tool isn't going to handle every aspect of steel design known to man, but I think it's helpful nonetheless.

Once I upload it to steeltools.org, I'll plan to update with a link on eng-tips, too. A sneak peak below:

 

[Cpw628]

I’m commenting to ask if you can update us if/when it gets published. I would be interested to see if it would be useful for my work. I’d also be willing to look over it before you publish to see if I can spot anything major

 

[RattlinBog]

Cpw629, Yes, that's the plan. Thanks for the offer, but I'll wait until I'm done in a few weeks to upload/publish it. I'd rather not have a draft floating around in the wild.

I already have a couple people checking it, and I also rebuilt the entire design aid in Mathcad to verify every equation. Also checked it with RisaSection and Risa-3D results.

 

[RattlinBog]

I'm debating whether I should add a part about considering pre-load (existing load at the time of reinforcing a steel member) to my design aid.

Bo Dowswell provides guidance and equations on how to determine if the reinforcement steel is "stabilizing" to the new built-up shape. Reinforcement is only stabilizing if it's attached to the compression flange and increases radius of gyration above 85% of the original shape r. If the reinforcement is stabilizing, preload can be neglected; if not, then preload must be considered. You can also neglect preload if the member is fully braced against LTB.

Anyway, would anyone find this useful in a steel design aid, or would it be better to check that on the back of a napkin? My spreadsheet is already massive. I'm trying to avoid adding too many extra features that could become overwhelming.

Also, while I can add these checks with some "if" statements, some engineering judgement would still need to take place as there could be other scenarios to consider that a spreadsheet might miss. I don't want to make it a black box.

 

[bones206]

To keep it simple, you could just have an optional field for the preload force, and include explanatory notes elsewhere. That’s how the SJI joist reinforcement spreadsheets handle it.

 

[lexpatrie]

You might be able to PM folks with the new site..

 

[RattlinBog]

To keep it simple, you could just have an optional field for the preload force, and include explanatory notes elsewhere. That’s how the SJI joist reinforcement spreadsheets handle it.

Good idea--I'll see what I can do.

You might be able to PM folks with the new site..

I'm not sure what you mean?


Would it be strange or against forum rules to post and attach my project report here in about a month when I'm done working on the design aid? I would probably remove the cover page.

Only reason I thought it would be helpful is because I describe the design aid's capabilities, limitations, and the steps I took to verify its accuracy in great detail. It will also include an appendix of a detailed Mathcad worksheet that's basically a duplicate of the Excel design aid but with clearly-laid out equations.

 

[bones206]

I would support you posting the file here. You’re not trying to sell anything or advertise, just contributing something worthwhile to the commons. I think it’s great and I can see myself using it quite a bit.

 

[EngDM]

I would support you posting the file here. You’re not trying to sell anything or advertise, just contributing something worthwhile to the commons. I think it’s great and I can see myself using it quite a bit.

Me aswell. If it isn't a protected file I'd be interested in going thru and converting to CSA standards for Canadian code use.

 

[RattlinBog]

Sorry, my question was about what folks thought about me also sharing my project report pdf on eng-tips. Would that be too much or against some rules? The report is 100+ pages and describes the development, capabilities, limitations, and accuracy verification for the design aid, as well as goes through a case study and lit review.

I'm planning to share/upload the design aid itself no matter what.

 

[bones206]

I don’t see any issue with posting the report. Goes hand in hand.

 

[lexpatrie]

Or a link...

(I meant you might be able to send somebody a private message if you wanted to let a second set of eyes look at it in beta. Exchange email there so your email remains (vaguely) hard to find for the spammers and the bots.