Good morning! This is Back of the Envelope – the place to learn structural engineering in tiny bites 🍪. In today’s article, I will talk about how to do a quick-n-dirty preliminary check to make sure your composite steel deck meets the fire rating requirement. This is something that confuses me almost all the time… […]
Webinar Recap: “Common Challenges in Wood Lateral System Layout”
In today’s post, I will quickly summarize what I learned from a recent webinar called “Common Challenges in Wood Lateral System Layout.” It was presented by Terry Malone, Senior Technical Director at WoodWorks, who has decades of experience designing structures. The webinar’s goal was to help us recognize things that we need to watch out […]
Skinniest Tower, Ever
This is a rehash of an article I wrote in my weekly newsletter, “Back of the Envelope” — where I teach you SE-related things in 5 minutes (or less), once a week. If you enjoyed reading it, consider subscribing at the end of the post to be one of the first to get new emails […]
Another take on the good ol’ “embedded posts and poles”
In today’s post, I’ll talk about something I learned recently related to “embedded posts and poles.” Quick overview: “nonconstrained” & “constrained” What exactly is “rigid floor or pavement”? Another option for “chain-link fence” (Estimated reading time = 3 minutes and 10 seconds)
P-delta diverging error was literally crushing my soul
Good morning. Andy here from Back of the Envelope — the place to be for all your p-delta soul-crushing info. Just kidding. No but seriously. Over the weekend, as I was working on a RISA Floor/3d model for a looming deadline, I repeatedly ran into the dreaded “P-delta diverging” error. It drove me crazy. So today, I […]
Site Walls and Earthquake
This is the first article that I sent out on “Back of the Envelope” — where I teach you SE-related things in 5 minutes (or less), once a week. If after reading it and you kind of liked it, subscribe at the end of the post to be one of the first to get new […]
Steel: Required Strength vs. Nominal Strength vs. Allowable Strength vs. Design Strength
Steel is actually one of my favorite structural materials. For some reason, the design outlined by AISC just seems much more straightforward compared to other materials (e.g. concrete). Perhaps I just had a really good professor in college… (thanks Professor Uang!) Anyways, if you are planning to take the PE or the SE but have […]
PPI Discount/Promo Code
If you are interested in getting the Structural Engineering Reference Manual and/or the 16-Hour SE Practice Exam for Buildings (both published by PPI), I got some good news.
Wood Design Shortcut – Beam Stability Factor (and Column Stability Factor)
Introduction If you have studied or have done some wood design, you certainly have came across the “beam stability factor”. It looks something like this ((NDS Equation 3.3–6): Now, I am not going to go into details about all the variables; I mainly just wanted to talk about the final CL factor. As you already […]
Three “Seismic Design Requirements” Flow Charts: The Quickest & Easiest Way To Learn The Design Values In “ASCE 7 Chapter 11 & 12”
While studying the ASCE 7 Chapter 11 & 12, do you frequently get lost in its”wall of text“? No problem, we are here to help! Ian has created and shared three very valuable flow charts (you can download them below). By following along while studying, you will gain a much better understanding of  many of the seismic design requirements […]