I recently came across a blog post by Prof. Amy J. Ko on how tenured faculty can accelerate the demise of tenure. Applying the same sardonic tone, here are five ways you can ensure OpenSees will also be gone sooner rather than later. 1. Don't learn - A firm grasp of linear analysis is sufficient … Continue reading Tips for Squandering OpenSees
Category: Community
Make a Pull Request
If a tree falls in a forest and no one is around to hear it, does the tree make a sound? If a model is coded in OpenSees and no one pushes it upstream on GitHub, does the model exist? Is there only the perception that the tree makes a sound and that the model … Continue reading Make a Pull Request
Means and Ends
OpenSees is often a means to an end, or an instrument, with the end being an advanced degree. There is nothing wrong with that! But OpenSees can also be an end in itself. You can learn to automate workflows, to think algorithmically, and to manage data structures--all in the context of earthquake engineering. That end … Continue reading Means and Ends
Your DLL Might Be Ignored
I am not a fan of DLLs (dynamic-link library) for material and element models in OpenSees. There are many technical reasons for my dislike of DLLs--fragile code, multiple versions swirling around online, keeping up to date with the latest OpenSees executable, debugging difficulty, and cross-platform compatibility to name a few. So, if you've published your … Continue reading Your DLL Might Be Ignored
You Get What You Give
In the early days of OpenSees, conventional wisdom was "You get what you pay for". Sure, the internet was around, but the only OpenSees resources were the wiki, the examples manuals, and the message board. Those resources are still around today. But there's a ton of other OpenSees resources available including packages, pre- and post-processors, … Continue reading You Get What You Give
You Didn’t Build That
At what point does a "customized version" of OpenSees become distinct from the main OpenSees? After tinkering with OpenSees, when does it become "your own"? In most cases, the answer to both of these questions is "never". Sure, you will learn a lot by implementing Concrete24, even if it is only an incremental improvement over … Continue reading You Didn’t Build That
Don’t Think, Just Throw
The uncertainty of an OpenSees analysis often stops people in their tracks. What will happen if I use this input for that model? Will I be able to simulate this behavior? What if the analysis fails to converge? Don't think. Just throw. https://youtu.be/qa3EseH3Hgc Nothing bad is going to happen if you have an incorrect input … Continue reading Don’t Think, Just Throw
Off the Hooke
To grasp nonlinear structural analysis, unlearn Hooke's Law, $latex \sigma = E\varepsilon$. And all derivative outcomes of Hooke's Law. Like $latex \kappa=M/EI$ and $latex {\bf K} {\bf U} = {\bf P}$. https://www.youtube.com/watch?v=z4jeREy7Pbc When steel yields, concrete cracks, etc., Hooke's Law no longer applies and holding on to it can lead to erroneous interpretations of nonlinear … Continue reading Off the Hooke
Minimal Working Example
When people post online or e-mail me about what could be a bug in OpenSees, I'll ask for a minimal working example (MWE), i.e., a simple script that demonstrates the problem. I don't want to deal with elaborate scripts--yours or mine. So, what does an MWE look like for OpenSees? Here's a non-exhaustive list of … Continue reading Minimal Working Example
It’s a Fine Line
The OpenSees Twitter bot started in December 2019 but didn't "like and retweet" #OpenSees tweets retroactively. So, out of curiosity, I searched Twitter the other day for the first use of the #OpenSees hashtag. This tweet from 2011 came up as the winner: https://twitter.com/drescolano/status/45099760868274176 Not an uncommon sentiment. Now, ten years later, I asked David … Continue reading It’s a Fine Line