## Communicating structural calculations

## Communicating structural calculations

(OP)

There is a disregard for the handicraft of writing and performing legible sequences of calculations in my immediate context. Trying to check or re-use even my own, let alone others, calculations is a pain.

I have been looking into literature or standards in an attempt to better this. Yet, most of the stuff I found is centered on general mathematical writing and therefore not as applicable. The only books I found directly dealing with the specific problems are Robert Motes books The Engineers Word, and The engineers Tables. Standards, on the other hand, seems to be specific to firms and not accesible from the outside. This lack is surprising, coming from an architectural background, where all aspects of drawings are highly standardized.

Therefore, my questions are these.

1. Are there any literature or widely available standards dealing with presentation and/or performing of structural calculations?

2. Do you know of any examples of sets of calculations available, to be used as a best-practices-example?

3. What do you consider to be essential qualities in regards to clarity when checking others calculations?

I have been looking into literature or standards in an attempt to better this. Yet, most of the stuff I found is centered on general mathematical writing and therefore not as applicable. The only books I found directly dealing with the specific problems are Robert Motes books The Engineers Word, and The engineers Tables. Standards, on the other hand, seems to be specific to firms and not accesible from the outside. This lack is surprising, coming from an architectural background, where all aspects of drawings are highly standardized.

Therefore, my questions are these.

1. Are there any literature or widely available standards dealing with presentation and/or performing of structural calculations?

2. Do you know of any examples of sets of calculations available, to be used as a best-practices-example?

3. What do you consider to be essential qualities in regards to clarity when checking others calculations?

## RE: Communicating structural calculations

## RE: Communicating structural calculations

I always thought '246 Solved Structural Engineering Problems' (by Buckner) is one of the best presentations I've seen for structural calculations.

Checking an existing structure makes things easier: you can reference the drawing/detail number in your calcs. That's one of the biggest headaches in looking at anyone's calculations for a decent sized project: wondering what they are actually running numbers on.

## RE: Communicating structural calculations

I agree with hokie66's comments above as well.

WARose, could you post a sample if you have one? I'd be curious to see how Buckner laid out the calculations.

## RE: Communicating structural calculations

Probably not without breaking copyright laws. PPI use to post a free sample of it on their site.....but I cannot find it over there now.

## RE: Communicating structural calculations

if I'm checking another engineers work, I find it much faster to quickly do my own calculations on things that 'just don't look right'. I almost never go through the other engineers calculations... I find it much better not to follow something and maybe get caught up in 'his/her' methodology...

Dik

## RE: Communicating structural calculations

## RE: Communicating structural calculations

If I do calculations that must be submitted to somebody, I use Microsoft Word. My next choice would be LaTeX, but I would have to do that from home.

--

JHG

## RE: Communicating structural calculations

I do the exact same thing. I write out everything, especially my thought process on why I did what I did, to make sure that the reasoning makes sense. I record important calls or conversations, along with any important references. My calculations are more like a journal of the project than anything else. Helps me a great deal when I am looking back a year later and wondering why I did something that looks ridiculous, I had a reason (whether good or bad, I had one).

Just a string of equations and numbers can be hard to follow real quick.

## RE: Communicating structural calculations

(ACEC put out a document called "A Guideline Addressing Coordination and Completeness of Structural Construction Documents", by the Council of American Structural Engineers (CASE).)

Link HERE

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## RE: Communicating structural calculations

In addition to what others have said, I have these thoughts to add:

1) It's always hard to review a one off hand calc. For that reason, I feel that it's hugely important to be using the same tools as everyone else in your organization, even if those tools might be inferior to your latest, VBA-packed, Excel Tour de Force.

2) I've been seeing some young guys and gals put together great stuff using MathCAD Express (or something like it) and Bluebeam (or something like it). The math will be easy to read and clips of the architectural elevations and code provisions will be dropped right in there. Slick. No need to sweat units or calculation errors. I find that the most common errors aren't math/code, they're a lack of understanding of what's actually going on and how asituation is typically handled. This set up sort of helps with that.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

## RE: Communicating structural calculations

We have an older copy. About half of it is a checklist.

It's OK but not sure it tells me anything I didn't already know.

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## RE: Communicating structural calculations

I disagree, for the reasons given by dik. Design inputs should be checked in detail, and the design process should be reviewed, but the design outputs should be checked with an independent analysis, preferably using different software.

Doug Jenkins

Interactive Design Services

http://newtonexcelbach.wordpress.com/

## RE: Communicating structural calculations

Are you sure? I have a hard time believing that anyone who's spent time in a high production engineering office would object to calc standardization. I agree that there is a place -- an important place -- for truly independent design verification. That said, I've yet to work at an outfit where there's been time or fee to independently check more than 10% of the work. Frankly, 5% is a stretch. And yet, junior engineers still need timely assignment feedback from their managers etc. I just don't see how that could reasonably be accomplished without a serious nod to standardization.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

## RE: Communicating structural calculations

I don't function well in a highly structured environment... I'm happiest when I'm working independently...

Dik

## RE: Communicating structural calculations

Then I'd argue that one of you should change your "way" to whichever method is deemed to be your firm's version of "correct". Kinda depends on what you're looking at. If you're splitting atoms then, sure, 50 shades of grey and let the creative juices flow. If you're checking punching shear at corner column, there should be something akin to a "standard" that everyone buys into.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

## RE: Communicating structural calculations

Thanks. I have some IBC checklist stuff that probably is in a similar vein. While it might not be enlightening for you or I, I wonder if it might be for other, less seasoned pros. I recently started a thread here asking if anybody had canned "how to do structural drafting" guides/checklists. I wonder if this document might fill part of that need. While I do care about how things look, I mostly care that information is complete and coordinated. And my need is for a way to train others that I may work with sporadically to help ensure that I get a product that I'm happy with. I'll see if I can talk my wife into buying this on her corporate account.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

I LOATHE looking at calculations in Excel; it takes extraordinary discipline to come up with a readable worksheet that has every units conversion factor clearly identified. And then, are the parentheses all in the right places? Both are easy do's in Mathcad, since units conversions aren't even necessary, and WYSIWYG equations look like the equations you expect to see in a textbook. Numerators and denominators look the way they're supposed to look.

While I won't go so far as to push Mathcad, per se, something similar would seem to be a good thing to standardize on. As with good coding practice, readability is critical to ensuring accurate calculation and ease of checking and validation.

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

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## RE: Communicating structural calculations

## RE: Communicating structural calculations

Hokie66 - I will try to implement that. Your advice is similiar to that given for general mathematics, which ill reconsider. My previous objection were that the plain amount of calculations + meta-text makes the whole document balloon. I guess its an experience call, knowing what is essential to communicate.

WARose - Thank you for the tip. I bought it at the spot, looks like a sound investment.

Motorcity - Do you treat the references as footnotes, or is there any specific way of referencing? We work mainly from the Eurocodes, so theres not that many obscure equations. I can imagine thorough referencing also help in standardizing the calculations between people, so that the use and context is easier to read up on later.

Drawoh - Word seems ubiquitous in this context, although Ive never understood its uses over Latex. Would you consider equations written in plain-text to be readable, or is the equation engine of word/latex critical? Ive been experimenting at home with a Markdown workflow recently, primarily using the fantastic software Calca and .css to standardize the pdf output. Its similiar to Mathcad, but with plain text at the cost of a cup of coffee. Problem is, it just doesnt look as pretty as a true equation engine does, although using Latex for the math and markdown for the rest is a possibility.

Kootk - Do I get your #2 point correctly as that the software which allows easier combinations of calculations with images support actual understanding, and therefore help prevent the large mistakes? That sounds reasonable, considering how useful it is to diagram next to hand calculations.

IRstuff - Yeah, its a world of difference between the readability of excel and mathcad. Ill try to emphasize that aspect a bit more.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

## RE: Communicating structural calculations

Microsoft Word has a perfectly functional equation editor. Click on the Insert tab.

I use Linux at home. I have learned LaTeX and I like a lot of stuff about it, including its equation display. This is what TeX/LaTeX was originally written to do. I can send the LaTeX files out in PDF format. The equations do not display well in HTML, and I don't think they display at all in RTF. I have not tried to do the actual calculations in Octave, to be integrated with LaTeX. This would be nifty and it should be possible. Octave calculations can be processed into graphs using GNUplot, and integrated with the LaTeX file. LaTeX can be run from a GNU Makefile, which is convenient.

Microsoft Word does an adequate job of formatting and displaying equations. I can send the results out as a readable and writable file, to be reviewed by engineers. I have done a number of safety calculations recently, and the results either were vetted (thread507-409684: Wind Loads), or they ought to have been vetted.

--

JHG

## RE: Communicating structural calculations

While Microsoft Word Equation Editor is essentially a free add-on, Mathcad is, unfortunately, VERY expensive. TKsolver is more affordable: https://www.uts.com/ItemDetails.asp?ItemID=0100-50... There's an even cheaper option, which is Mathlook for Excel: https://www.uts.com/ItemDetails.asp?ItemID=1100-40... I've never used it, since I have Mathcad, but it might at least get you a pseudo-self-documenting worksheet.

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

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## RE: Communicating structural calculations

I agree. I wasn't suggesting that everybody be proficient at the same software. And I recognize that 100% standardization is wishful thinking. What I'm talking about isn't ETABS/RAM stuff, it's the dozen or so company vetted spreadsheets that most offices maintain for doing common things. You know: spread footings, openings in steel beams, column load take-down, yada yada. It is my strongly held opinion that, where such internally vetted tools are available, they should be used with very few exceptions. In my experience, at least 80% percent of EIT, one off spreadsheet will contain an error. Seriously.

That's precisely what I was getting at. Doing a meaningful review on a endless, streaming effluent of numbers is painful and time consuming at best. The accompanying sketches are the most valuable part I feel. How did you decide you're trib area? Unfortunately, because hand sketches take time and force folks to go non-digital, they seem to get used too sparingly. Clipping and pasting sketches into some kind of digital scratch bad seems to produce excellent results. As an example, a rockstar EIT that I used to work with would give me calcs like this:

- Load casing done in matrix form so that you could easily see what when into determining max/min without having to wade through the results of every combo.

- Pasted snippets of the code provisions where it wasn't completely obvious what code provisions had been drawn upon. Folks mostly have access to digital codes now so it's easy.

- Snippets of the framing plans with hatching showing the trib areas for beams. Same for columns with snips of the architectural sections to show unbraced column heights.

- Snippets of SAP2000 results. Moment diagrams, deflections etc.

It's nice, as you can imagine. In this day and age, it's all to often the case that "checking" means getting directed to some folder full of models and half baked "spreadsheets". Easier just to redo the design myself. And I'll do that for some spot checking at the end. Mid-project though, I need to be able to see that things are being done correctly in order to keep the project on track.

## RE: Communicating structural calculations

Dik

## RE: Communicating structural calculations

The version I've got is from 1991. I think there is a later one. But I love this one because all the solutions are hand calcs. It's like looking at a good set of calcs from a older engineer.

## RE: Communicating structural calculations

For fancy stuff I use LaTeX. For a faster typing I use mathcad and then use a mathcad to LaTeX parser I found on the internet a while ago. This helps make calculations faster. And the document is pretty.

When I work with people unfamiliar with LaTeX, then Word is the way to go, but it is a pain in the ****. When I learned LaTeX I forgot everything about Word.

About the completeness of the calculations, when doing obscure works (e.g., complex shells) where I work it's standard to make the calculations a little bit less legible such that only the reviewers (people who know the calculations) are able to understand it, so people unfamiliar with the subject feel a bit lost. This typically involves removing steps and using obscure symbols. For handwritten calculations just copy your doctor's handwriting.

## RE: Communicating structural calculations

If your complex shell collapses, your undecipherable calculations won't help you.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

In the process I ended up reusing huge chunks of spreadsheets for similar projects. By the end of my tenure there I had automated 75% of my day. I could show up and work 2 hours a day, spend another 2 developing increasingly complex mathcad sheets, and read/study/relax the other 4. The supervising engineers were hesitant to give me any more work because I was already pumping out so much.

Refusing to use mathcad because it takes too much time is akin to refusing an offer of 100$, to be given next month, to receive $10 today. You will save time, and the benefits will be realized very soon.

## RE: Communicating structural calculations

Whatever...it is a poor idea to intentionally obfuscate.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

I am trying to get to this point with Mathcad and have made a few sheets for repetitive stuff that I do. The biggest aggravation for me is that I do a lot of one-off custom calculations that rely on hand sketches and free body diagrams to explain. I'd like a quick and easy way to import a hand sketch to the Mathcad sheet alongside the calculation. It seems by the time I sketch it, scan it, import it, format it after it throws off the sheet layout that it's quicker to just do the calculations by hand.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

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## RE: Communicating structural calculations

Those of you using LaTex and/or Word may want to look at using python along with Jupyter notebooks or SageMath.

## RE: Communicating structural calculations

I hear 'ya on that. I've always thought it a bit cruel how things work out for our ilk. Being good at doing production requires a degree of attention to detail bordering on autism. Being good at managing the production requires one to be a "more than one way to skin a cat", 80/20 kind of guy/gal. It's rare that both skill sets come naturally to the same engineer.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

- Crap backwards compatibility.

- Bought out by big parent company.

- Expensive. They just ditched perpetual licensing and subscription is $600 US per year.

- Somehow, Prime 4.0

stilldoesn't have as many feature as V15 had back in 1859.SMath Studio is looking better all the time. I know it has some limited programming features which is great. Does it have things like goal seek and hidden regions? Talkin' to

yourn14.I'm more than a little bitter about MathCAD really. Around 2000, I placed my bet on MathCAD being the future and let my Excel skills slide. I regret that choice intensely now. Trust. That is what is now absent from my relationship with MathCAD.

## RE: Communicating structural calculations

My new TI calculator is proving to be very useful... it does a form of 'pretty print' and I can print the files to a *.pdf file for saving. Can add comments or can just do 'meatball' calculations... it saves them all. It has a spreadsheet that easily rivals excel and for more complex operations.

MathCAD went downhill and the price soared when it was taken over by the 'bigname' company.

Dik

## RE: Communicating structural calculations

---

http://be.linkedin.com/in/fusionpoint

## RE: Communicating structural calculations

Dik

## RE: Communicating structural calculations

There's a bit of a Mathcad flavor in a couple of the examples. Their website's a bit clunky, though

Thanks

TTFN (ta ta for now)

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

## RE: Communicating structural calculations

I usually scan diagrams/sketches into a PDF format or Jpeg. Then I use windows free screen snipping tool to cut and paste into Smath.

The best thing about Smath studio is that it is free!

## RE: Communicating structural calculations

## RE: Communicating structural calculations

These seem contradictory; Mathcad, at its basic level, essentially does "hand" calculations and documents them as you go along. There may be something to be said about doing them on a calculator, but Mathcad allows you to avoid making mistakes in unit conversions, etc.

How do you document your hand calculations? Do you write them on a sheet of paper?

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

## RE: Communicating structural calculations

Like I wrote, I know I'm in the minority on this one. But I also prefer wooden pencils to the mechanical ones, wood furniture to particleboard furniture, unlined leather boots to goretex ones, brick vs. vinyl siding, homemade pies to store-bought ones, manual transmissions, rear wheel drive, etc., etc...

## RE: Communicating structural calculations

## RE: Communicating structural calculations

I try to do as much as possible where I avoid hand entering numbers more than once. Everything after the initial data entry is copy/paste only.

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

## RE: Communicating structural calculations

On the other hand, we also sometimes get reams of paper with nothing but numbers. (Equally useless.) Manual calculations are becoming a rarity. This is not good.

I don’t want to “process” calculation submittals. I want to review them to be sure that the person who did the calculations has a clue.

## RE: Communicating structural calculations

You sometimes take a little extra time to intentionally make your calculations confusing and difficult to understand? Respectfully, that is not a good thing to do.

Unfortunately these days, it seems many engineers don’t intentionally strive to make their calculations undecipherable. They are just naturally a confusing mess.

## RE: Communicating structural calculations

If you were bashful about say it, I’ll add a couple sentences to the end of your last post. The calcs. are a mess becuase the people doing them (engineers?, come on) don’t have the vaguest idea what the hell they are really doing. They have no engineering experience or judgement to guide them, they have no intuitive understanding of how the structure works, they don’t seem to have a boss that gives a damn or gives any meaningful guidance, just get er done and out the door. We have E&O insur. to cover the rest, or any problems you produce. They can’t do the problem or analysis long hand, they just don’t know how. They couldn’t do it without the software they were given to use, and they really don’t understand how to use that software, or model the structure, or how to interpret its output either. So, you get a ream of paper with numbers on it, and it is the old saw..., ‘dazzle them with data, baffle them with b.s., and maybe they will go away.’

## RE: Communicating structural calculations

Off topic but this made me laugh.. I just had my house re-plumbed; the estimator came and gave me a quote on the spot, in writing. I looked it over for 10 seconds and asked him to re-estimate using copper line and fittings instead of PEX.

He looked at me as if I'd just told him I was born on Venus and wanted my home's plumbing to be constructed from chocolate and vanilla frosting.

Back on topic..

As usual for any post I write in the SE forum, I deal with a reasonably different scenario; much of the calculations I deal with are either FEA results or quick calculations of a small aspect of a system.

My approach is always the same- I don't ever read a ream of calculations line by line looking for errors; I just take the same inputs, units and assumptions (or model and conditions if we're talking simulation) and see if I get the same result.

Granted, repeating the work is maybe not feasible for something like evaluating the engineering of a whole building, and there are other drawbacks with this approach; but I've found that if I take a couple of pages of calculation and start stepping through line-by-line, it can often become difficult to avoid getting locked in to the other person's assumptions when they may not be correct.

This, of course, requires that me and the person I'm backing up or evaluating have access to all of the same tools and documentation, which again may not be possible if you're evaluating things after the fact.

## RE: Communicating structural calculations

For 'simple' calcs I will usually just overmark the design drawing and add any checks at the side.

For 'moderate' and 'difficult' calcs I will do something like below using MathCAD.

Intro: Describe the project, what I am checking, any obvious constraints, problems. Why I'm going it the way I am doing it.

Methodology: Only for complicated / long calcs, I'll include a step by step break down of what I'm about to do so the checker is forewarned.

Assumptions: Any assumptions go here.

Loading: Details of the applied loads, load cases, factors etc.

Structural System: Describe how the loads are transferred / resisted. Sketches!

Calc Part 1: Brief text description of what I'm checking, sketch if required (I try and work from the applied load to the foundation, checking what's relevant as I follow the load path). Calcs, with descriptions next to each parameter / equation to aid understanding.

If I do any computer modelling etc. then I will include screenshots from the model, showing e.g. geometry, section sizes, applied loads, bending moment / shear etc. as relevant, utilisation plot.

I do usually rely on the checker poking at the model a little bit as well as reading the calc report.

etc.

Conclusion: State what has been checked, what is OK, max. utilisations, etc. Any restrictions on use (e.g. max. load of 5kN/m2 only) etc.

Appendices: Drawings, reference data, print out of relevant pages of standards, etc.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

KootK, can you describe this in a bit more detail? What were they clipping sketches/code provisions into - MS Word file, MathCAD? Could you post a sample by chance?

What I like is doing all the wordy parts of a particular design (say, designing a steel beam-column) with a sketch by hand on design paper, then use my typical beam-column Excel spreadsheet to do that actual computations/code checks. THEN, write on the excel print out any notes or relevant info, and finally staple the pages together.

## RE: Communicating structural calculations

## RE: Communicating structural calculations

I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg

## RE: Communicating structural calculations

I use a pdf printer driver with my computer and create *.pdf files of my spreadsheets, etc. and copy these to the project file. If needed, they can be printed out.

Dik

## RE: Communicating structural calculations

One other point I'd make is any external peer review shouldn't substitute for robust internal verification.

## RE: Communicating structural calculations

I typically fully draw the detail as it will be shown on the structural sheets using seat-of-the-pants engineering and some quick calculations.

That way I have already worked out the constructibility issues.

I then print it out on 8 1/2x11 and add the actual confirming calculations on top. It is easy to draw arrows to each connection or member and show the calc for it.

## RE: Communicating structural calculations

Link

Have not viewed it yet so cannot attest to its usefulness,but thought others might be interested.

## RE: Communicating structural calculations

The only purpose of calculations is to help an engineer make a decision. And humans, generally, can only make a decision after they've framed the problem in context of a story.

Therefore, your calculation better be written as if it was a story to help you, your future you, or someone else make or understand the decision at hand.

"We shape our buildings, thereafter they shape us." -WSC