Wood-frame lateral design software 6

[cupola21]

I'm thinking about developing a software that can perform wood-frame lateral design. The software will follow the methods as detailed in the book "The Analysis of Irregular Shaped Structures Diaphragms and Shear Walls". It should allow people to import CAD to build 3D model like you normally do in RAM Steel but analysis is driven by analytical methods in the book. It will take care of things like transfer diaphragm checks and horizontally offset shear walls.

The target project will be typical mix-use 3-4 story wood-frame projects. Probably overkill for small residential project I think.

Will anyone be interested in something like this? Or do you use software for wood-frame lateral design?

 

[skeletron]

I love Malone book and Diekmann's papers, but have to agree with milkshake that it's a struggle to follow...like watching your prof flip overhead slides with one line equations and a final answer, onto the next section! Still, it's a book that needs digestion. Malone does mention at the start of the book that it relies heavily on visual analysis. After trying to program one of the examples, you can kind of manipulate it a bit but my novice-level programming still has some intelligence issues with the signs that requires manual work.

HOT TAKE 1: Personally, I can't see a huge benefit with getting a highly tuned FEM light-frame wood model AND having that be executed in the field. You'd have to build the structure like it was a videogame, laying out panels, adding straps here, 0.131" nails for here...and then you'd need to be full-on daily monitoring of the build which doesn't seem to be how many firms/contractors want to roll. it might be the wrong tool for the job.

HOT TAKE 2: Why isn't more prototype testing being done on irregular diaphragms/walls? The last report I read had a full scale shake test on a box.

 

[milkshakelake]

@skeletron Regarding hot take #1, detailing with straps and collectors makes it difficult to build. I haven't seen a medium scale wood project with my own eyes actually have straps and collectors in the diaphragm; the ones I saw were built like 2 story houses. I had to instruct the contractor to put them in, despite lots of references to details.

Getting a bit off track here, but what the heck. Malone uses wording like "tearing of the diaphragm will definitely occur" but either it doesn't happen in real life, or we need a few more seismic events to load test these buildings. Also, from forensic case studies, it seems like lateral wood failures are generally due to no hurricane ties or too few shear walls, so I question the premise of the book but still follow it religiously so I don't get accused of underdesign. /end rant

 

[ChorasDen]

I wrote some software about a year ago with regards to this very concept, the design of rigid wood diaphragms for 3-sided, 4-sided, cantilevered, and other configurations. The tool analyzes both the diaphragm itself, as well as the shear walls supporting the diaphragm, and can be designed with standard wood shear walls, as well as Simpson Strong Walls. See the attachments for example outputs of the software. This software also provides shear diagrams for the diaphragm itself to help visualize forces within the diaphragm, and provides detailing for where blocking is required. The entire analysis is based on Terry Malone's work.

Cupola, is this what you were thinking in your OP? If so, I'd be happy to consult with you on various implementation methods if you'd like. Is there interest out there for this type of software? I wrote it for personal use, but I wasn't aware that there was much interest in the community for this kind of software.