Do I need to consider hat truss with overstrength factor? Sketch below. This one is a vierendeel truss. I'm not sure what to make of it, if it creates soft story/vertical irregularity or not. I'm inclined to think that it doesn't, because the stiffness of the lateral system is a collective unit...
Seismic drift is limited to 0.020 in a building I'm designing with Seismic Design Category B. I'm using 0.35Ig for cracked walls and 0.7Ig for uncracked walls. Can I increase the moment of inertia by 1.4 as noted in ACI 318? I kind of know the answer already, but I'm just double checking...
Is there a code reference for allowable deflection in a soldier pile retaining wall? It's about 13' tall with 3x8 lagging, holding back sands. The use of the retained soil is sidewalk and backyard. I'm currently calculating 3" to 5" (depending on the steel size), and it seems high to me. But I...
Is there a reference for how many optical monitoring targets are needed on a building? This isn't for a specific case, just general. But an example would be if I'm drilling soldier piles (that cause vibration) next to a 4 story building owned by a neighbor, so I need to know how many targets to...
Anyone have a detail for how to connect a cold-formed steel beam (like a box beam) to a cold-formed steel column within a stud wall? I'd like to do this with platform framing, i.e. not a continuous column.
I've shown the detail I've been working out below. It's in progress so it's missing some...
Client wants to make an opening in an existing rear wood wall. This wall is about 100 years old and definitely wasn't designed as a shear wall, but functionally, it's a shear wall. When it comes to ASCE 7 code, alterations/removals to shear walls will require shear walls added somewhere else...
Question:
Why do some engineers use significantly longer 90 degrees hook lengths than is required by ACI code? For example, having the leg be 24" long for #5 bar, when only 10" is needed.
Background:
Per ACI 318-14,
So #5 needs 10". This is also shown in CRSI manual. However, I've seen...
How do you specify the material of round soldier piles? I'm speaking to a soldier pile supplier. They explained:
1. Prime Pipe is made using API 5CT specification, which has strict mechanical and chemical properties.
2. Some stuff isn't good enough for that. This is called Mill Secondary...
Is it possible to post-install column ties in a foundation wall?
I have a foundation wall that was installed without transverse ties, but it has a concrete column on top of it with about ultimate 450 kips axial load. Per ACI 318-14, ties are required:
I have some relatively small 2 to 3 story wood buildings I need to design. Is Risa 3D good for this? I need to calculate joists, studs, jambs, headers, and beams. I'm downloading their trial right now, but I'm wondering if anyone has long term experience with this software.
I currently design...
I'm adding a steel beam under the 2/3rd span of existing joists, since the joists fail without the beam. These are my details below. The issue: the joists are not level, so some of them need shims. How do I install these shims? I'm mostly worried about nailing between the joist, shim, and sill...
Does this work? I'm not 100% sure how the unbraced length would work; maybe each channel is fully unbraced, which would make it very hard to work with.
I have a 100' long building that's being shrunken down to 60' due to zoning issues. Generally when I extend a building, I know that ASCE 7 requirements must be met for the entire building for 10% or more addition. But if I shrink it, does that still apply? The goal is to keep the existing front...
I have a million projects due this week, I'm understaffed, and I can't finish everything. Clients are calling all the time with problems on site or asking for drawings. Is it possible to maintain peace while being like this?
For context, it's not always like this. Usually, I can send everything...
I'm designing a CMU wall as a moment frame. It's an existing 8" reinforced CMU wall (with 4" brick face) that needs to be upgraded for lateral. I'm going to replace some of the horizontal "CMU beams" with concrete beams. Anyway, do I need to check diagonal shear around the window openings? And...
I'm looking for an alternative to Matterport. It's a 3D photography solution that allows measurements and walking around. It has been tremendously useful on a few projects for structural inspections (I didn't do it myself, it was provided by clients).
My issue with Matterport is that it's...
I'd love to get a second opinion on the flat slab layout shown below. I think it's okay personally. The load path seems okay. I'm only concerned about the area shown with markups.
I'm not talking about walking columns. I mean columns placed on top of each other with an offset. Are these okay? What things do I need to be concerned about?
My punching shear senses are tingling. I'm immediately thinking of punching shear issues for overhanging portions of columns sitting on...
I think I know how to do this but I need a quick sanity check.
I have 2 wood stories supported on concrete piers, while the rest of the building is supported on typical spread footings, due to sloped grade. For the area supported on piers, my initial thought is that I'd need concrete or steel...
I'm extending a slab. Removing an old slab that's 2' higher than the rest of the floor level, and leveling it out. Do I need to worry about continuity?
I could look into alternative schemes like adding beams, but that will affect headroom. I prefer to extend the slab. But extending it means...
