Thanks all, helpful to get some other opinions. I think I'm going to leave it on there and see if I get pushback from anyone. Like TRAK said, i'm guessing that residential concrete subs are just going to keep using whatever mix they always do.
If it were me I would avoid framing into that chimney. I would do a flat beam at N-S walls plate height in front of the chimney and a king post down to it from the ridge. Or a bent steel beam. that way you might be able to avoid adding load to the existing foundation too
What do you all call out for air content in residential concrete? Specifically foundation walls and footings. I've been revamping my general notes and have seen other engineers specify no air, 5-6%, or not mention it at all. No air seems to be the most common.
Based on the ACI I'm coming to the...
For light loads (under 1k) it doesn't bother me too much. I've used it in this orientation a lot and haven't ever noticed splitting but I can't say I've been looking out for it. A simpson rep told me once that they use a factor of safety of 4 on their hangers and I usually scale down my hanger...
@davidl13
I live/work in a high wind area. My process for this is to do a quick lateral analysis of the building using the SDPWS (once you've done this a few times you can do it pretty fast). Most of the houses around here pre 2000's are primarily held up by drywall from a lateral perspective...
Thanks for all the great responses. This is all super helpful. I've got a lot of reading/research to do now. I'm also waiting for a call back from Risa and will let you know if I find out anything informative.
Assuming that you aren't having bearing or frost protection issues with that detail. One idea is you could do a steel embed plate and then weld a knife plate to it with thrubolts into into the post? Or you could drill epoxy anchors through the post and into the foundation wall.
I'm being asked if I can design a glass railing for a client. I'd like to learn glass design and I don't mind eating it on my fee to break into it, but this project doesn't warrant buying an expensive software like RFEM. My project would be a glass panel system with 2 circular glass clamps at...
@Greenalleycat - Thanks for your example. Fortunately I have a pretty solid tread configuration with a flat plate that extends almost to the edge of the tread and a vertical fin on the front that stiffens it up. I have done treads in a similar way to your example before and had the same...
Good points and thanks again for your thoughts on this, they've been very helpful.
At the 2 points where I'm connecting into wood floors I will definitely have them add blocking and coil strap to drag some horizontal load into the diaphragm.
Unfortunately the handrails will be attached to a wood wall primarily.
I agree that the welded angles won't help much for torsional strength but they do almost double my Ix (transformed section) which makes a notable difference in the AISC vibration calcs, about 20% increase in Hz.
Thanks for...
@KootK thanks for your insights.
I'm using Risa 3d which does have a setting that you can turn on to account for torsional warping so I think I'm set there. I also have some extra stiffness left unaccounted for from the L4x4 angles that are welded to the top which makes me feel better.
As far...
@Phuduhudu Thanks for your response! I do have seperate load cases set up where each tread is only loaded on one side. The 300# pt load is producing the worst deflection because I modeled it right at the end of the tread. Thanks for the article too, I like the idea of using a smartphone to...
