Decompression of an aircraft cabin through a skin rupture. Could solve for any altitude, initial pressure in the cabin, and rupture in any compartment (there were 14 compartments).
Out of hundreds over 25 years, it is hard to pick one.
Lol, probably my section properties spreadsheet. It is nothing more than a table with A, y, and Io for each element. Solves for basic section properties. I have used it God-only-knows how many times.
I made one a long time ago with a bunch of macros in it that would check each member of a cold formed steel truss after dumping the FEA output.
Really streamlined the process of design.
The one I like to show off the most is my 3 column bent (AKA pier) design. Getting it to combine all the possible combinations of 10 foot wide truck loads in 12 foot lanes was quite a trick. Getting it to report back the not only the controlling reactions, but also the combination that produced it, took some work, too.
I'm also pretty proud of my bridge girder bolted field splice design spreadsheet, which was used as the template for that module of our widely-used bridge analysis software.
My wife created a spreadsheet for me that multiplies alphabet letters as a base-26 number system (z=0, a=1, b=2, etc.) I used to have aspirations to think in base-26, but got bored with it and moved on to other wastes of time...
The simple-er spreadsheets like Snow & drift Loads, Seismic Loads, Two-stage seismic, wind loads on open structures, etc. are not cutting edge by any means, but I use them so much that I'm really happy I spent the time years ago to make them. These types of spreadsheets save me some amount of time on nearly every job so it adds up long term.
Mine is one that I made at my first job as an intern for a solar company.
Take in a home owners monthly electricity consumption. Also the electrical rate structure the home owner is on is input.
Spread it out over 8760 hours per year using a synthetic (unit) consumption load.
Use weather data to determine average hourly solar insolation at the site.
Use efficiency and array tilt angle to determine hourly average solar power generation.
Solve for net electrical consumption reduction in a year and determine average savings due to solar.
Finally calculate the payback period of a given solar system.
Of course I have many structural spreadsheets and programs that I have built over the years but I still love this one the most lol.
Got many with calcs, and one for welder certs that is really elaborate (and nice), but the one I use the most is the one with all of my online accounts and their passwords...
![[pipe]](/data/assets/smilies/pipe.gif "[pipe] [pipe]")
