I have a project where we are adding to an existing building and adding on, for all structural intents, an ICC-500 rated shelter. The construction of the shelter is 12" CMU exterior walls, grouted solid, and 12" hollow core planks with 4" composite topping, all designed for 250 mph wind loads...
We currently have a project under construction that has an ICC-500 shelter as part of the project. It's a precast concrete box with a hollow core floor bearing on interior 8" CMU shear walls with #5 @ 24" o.c. and a grouted bond beam at the top of the wall.
The issue is that the CMU walls were...
Thanks all for your responses. JAE, what you described is exactly what I was thinking. BrianPeterson, if this had been a contractor, then yes, I would agree.
IR, I also thought it was weird, and it's always good to double check, because as it turns out, it hasn't been constructed...
So I can...
Our firm has a long-time high school client that had their shop classes construct an "Outdoor Learning Environment" (which is basically a wood shelter house) as part of their curriculum. The shelter has already been built, I believe that they had filed permits, but the city has now told them...
I'm working on an addition to an existing building and during demo, the contractor discovered the situation shown in Photo #1. It's an existing W21x44 bearing at the end of a CMU wall and the CMU under the beam bearing has cracking. There's a 1/2" steel bearing plate below the beam with...
StructSU10, I assume that after you adjusted your K, you still used the Ix of the original column then in your critical load formula? I’m sure that the paper will probably explain further, so I’ll take a look at it tonight. Thanks for sharing.
Either way, I think I need to increase my...
I appreciate everyone's input. It's brought up a number of good points.
I think bracing in the direction of the joists is more complicated than I initially thought. I hadn't thought as much about bracing effect on the joists, only that they wouldn't put as much load in the brace as the beams...
Here's a link to a quick plan sketch and elevation of the columns. This is in an existing building and the columns are buried in l.g. demising walls, so I was trying to minimize demolition and interruption of use at the building. The easiest way to do that was reducing the braced length with a...
This came up in the thread765-368271, where existing columns were noticed to be under-designed. In discussing how to remedy the issue, I was looking to simply decrease the braced length of the columns by adding a bolted T-C brace in each axis, angled at 45 from the column up to the roof...
So the column would have a reduced braced length, but even if I use tubes for the braces, won't the brace up to the beam take some of the gravity load from the beam as the beam deflects under snow/live load? This would be an angled axial load that would then induce a horizontal force at the...
I spoke with the architect and convinced him that we need to change the columns in new building because I wasn't comfortable using the demising walls as bracing. I really wasn't too concerned with getting push-back on that aspect and didn’t receive any. So in regards to the new building, I...
I really do appreciate all the feedback. On it's face, this almost seems like a dumb question: "Should I tell the owner if their building is deficient or not?" but as many of you have pointed out, there's a lot of latitude in how things are designed and where engineering judgement comes into...
Thanks again for the additional replies. After rereading my original post, I realize that it may have come across somewhat like Chicken Little in that I did not give enough detail to explain that this is a single story building. And, while not trying to undersell the possible importance of the...
I recently started work on a site-adapt project for a public building that has already been used on another site. The structural engineer that did the previous design has since retired and I was tasked with the structural design of the new building. I rechecked the calcs from the previous...
My firm has a typical detail that places the CJ at the corners of the opening similar to 2a and 2b in the link above. We have another detail for bond beam reinforcing to stop each side of the CJ and a single bar, with one end taped to prevent bond, extending across the joint. We call for...
I did not run new numbers on the PEMB, I'm using the lateral force at each of the columns, that was given on the original PEMB drawings.
The new floor is compeletely independent of the existing building. We did not connect any piece of the floor to it for gravity or lateral purposes, so the...
No, I had tie-footings between the exterior foundation and interior footings underneath the slab. So the savings are more substantial than just removing hairpins, roughly $10-$12k, is what the contractor estimated.
In rereading my post, it may have been a little unclear that the "independent...
I’m working on a renovation of a PEMB which is having the slab removed and replaced and an interior independent floor put in. We didn’t have any information or drawings on the size or reinforcing in foundations or slab other than an e-mail from the original contractor saying what he thought the...
