Recent content by rn14

Exactly. Even as a rigid diaphragm you would have to resolve the torsion created by the offset of center of mass and center of stiffness which is what you are doing with a three sided building with a flexible diaphragm.

If you don't want to run full length collectors you need to detail out the transfer diaphragm. Whether it is a flexible, rigid, or semi-rigid makes no difference. My concern is more how you are determining the diaphragm is rigid. I agree that in reality screwed and glued diaphragms with heavy...

This is the least expensive place I have found https://www.suncam.com/

All those that like or are considering Mathcad should take a look at SMath Studio. I like Mathcad and all but at $1000 a seat I feel it is way to expensive considering you are basically buying a program language. They are also awful about breaking old sheets with new versions. Those of you...

I noticed in the webinar videos the beams between lateral frames are assigned to "gravity". Am I wrong thinking these beams should be "lateral" since they will act as a drag member to get load from the diaphragm to to lateral frames?

Variations of this discussion have occurred here before. My particular case falls within exceptions where I can use R=6.5 for shear walls and R=3.5 for the OMF (rather than 3.5 for everything). That makes me happy. I wanted to be sure I am reading exception 3 of 12.2.3.3 of ASCE 7-10 correct. If...

I'm in the same boat. On complex residential projects I find myself using so many different programs and spreadsheets it is a nightmare. I have tried risafloor and 3d for it once or twice but floor can be a real pain with multi-level and pitched roofs. Gerry has an interesting workflow though, I...

Dan Kuchma moved from University of Illinois to Tufts. You could try emailing him. I tried a few months ago with no luck. http://engineering.tufts.edu/cee/people/kuchma/

Jeff, I don't have any sketches at the moment. Although a general question, the particular case that raised it this time is that we have been asked to design some "winch anchors" for snow grooming equipment. The want to try and use round tube that they already have. There would be 3 forces...

I'm curious on opinions about using FE analysis for unusual steel connections. More specifically, using plate/shell/solid elements to model a connection that doesn't fit into anything in AISC. Do you ever do it? Do you just look at stresses? Do you accompany with some hand calcs to check plate...

Thanks Jay. That makes sense I guess I was more curious as to why this became unstable due to the shearwall placement.

Joints N1 and N5 which are the bottom joint at the left steel column and the top joint at the right steel column. The locked DOF is MY (moment about vertical).

Hello all, I am trying to model a steel frame with a wood shear wall which seems like an easy enough task. The columns are pinned at the base and the beam is simply supported. When the shearwall fills the entire frame everything is dandy. When the shearwall only fills a portion of the frame Risa...

I think the best way is to turn off the physical member property of the beams with walls below. Seems to act as expected.

Jay, it isn't out of the question. Josh, I had thought about that. So would you just copy the node at the top of the last 2 columns down and inch or two and connect your wall panel there?