Ahh, ok. Yes, you are correct. When you said "both coefficients" you were referring to 2 and 2E not windward (2E) and leeward (3E) like I had assumed.
Juston Fluckey, SE, PE
Engineering Consultant
That's not true. If the leeward is more negative than the windward, then the net pressure is positive. Remember, the wind pressures are normal to the surface. So on the windward side, a negative pressure has a horizontal component in the opposite direction of the wind. On the leeward side, a...
Deker,
Thanks! That one looks promising. I'll pursue that one if the client comes back and confirms the 3" thickness. They told me 3" but they originally said 4". So I just want to make sure they don't really have a little more than 3" which would solve everything.
Juston Fluckey, SE, PE...
SE2607, attached is an example of my wind calculation using Chapter 28 of the ASCE 7-16. I convert the Chapter 28 pressures into equivalent net pressure zones (Wall Zones A & C and Roof Zones B, D, E, F, G, H), so I don't actually give you the GC values of the Chapter 28 zones. But I did confirm...
Use caution with this so that you don't double dip. If you multiply your pressure by sin(20), then don't use projected areas. You'd have to apply that wind load on the full length of the roof member. If you don't multiply your pressure by sin(20), then you can use projected areas on your roof...
This is less a engineering question and more a product question. I have someone wanting to anchor to an existing 3" thick, light-weight slab in seismic design category D (cracked concrete). I can't find any anchor that is tested in anything less than 3.25" (1/4" Hilti KB-TZ2). LRFD shear load...
pham, I created the spreadsheet because you gain so much knowledge (if you can verify you are actually doing it correctly) when you create a tool from scratch. You never have to wonder what the program is doing behind the scene. I spent a lot of time on that spreadsheet manually entering the...
Jeb, I live in TN near the KY border. I appreciate when states don't adopt a code just because a new one is available. In most of these midwest states, the old codes work just fine or there would be more building damage which would prompt a change in the code. Indiana (where I moved from) is...
Pham,my biggest question in the IRC concerns braced wall lines. I just can't wrap my head around the requirements or what is actually supposed to be used. No hold downs? I'm coming from shearwalls which always have corner hold downs and braced wall lines may work, but only if you use them as the...
I think IBC has vetted it. It is scheduled to be adopted in the 2024 IBC. I don't like mixing/matching different codes/standards either. Just like the 2018 IRC uses 2015 wind values when the 2018 IBC uses the newer wind speeds. I don't do residential except for one client, but I do an engineered...
Well, I'm a modular building engineer so I do work for almost all states (licensed in 47 jurisdictions), so I've got to use almost of all of the various years of standards out there. FL just seems to always be difficult (almost as bad as CA). FL also requires real digital signatures. Most other...
I thought it would be another year and a half before I had to worry about using the ASCE 7-22, but I just discovered that the new FL building code (8th Ed) coming effective in January has adopted the ASCE 7-22 (per chapter 35) in lieu of the ASCE 7-16 which should have been adopted since the 8th...
Well, sorry everyone. It seems my wasted time has wasted your time. Apparently the test reports that I was sent were historical tests for the mixture, not the actual in-situ concrete. The actual concrete hasn't even been poured yet, so this "letter of approval" request doesn't even make sense...
@PT99,
That's where I am at too, but my lack of in-depth ACI knowledge might have kept me from another avenue that could justify this. It is 3/4" aggregate and could be might be able to be classified as F1, which ACI 318-14 Table 19.3.3.1 says the target air content is 5%. F1 is "Concrete...
@dik,
Massachusettes, so yes, freeze/thaw would be common. The building is on piers and the bottom of the building will likely be skirted like a mobile home. So, the foundation is under unconditioned space with no real protection from water.
Juston Fluckey, SE, PE
Engineering Consultant
@flight7,
I never assume temporary structure unless very apparent. Most of my work is in the modular world and, like you said, many will claim a life at site at 2 years or less, but that doesn't mean they don't intend to leave it there much longer. Since there are poured concrete and weld...
@Once20036,
I am an SE/PE that sealed the modular foundation plan. Thank you for bringing my signature to attention. I haven't looked at it in years and I let my CWI expire since I never used it. I'm going to go update that now.
Juston Fluckey, SE, PE
Engineering Consultant
I'll admit that concrete knowledge is the weakest amongst building materials, so I only get involved in very simple concrete things. Well, I am being asked for a letter of approval for the concrete used in sonotube piers used for bearing and lateral resistance of a single-story modular building...
JLNJ,
I think that is the case with most of the sleeve anchor manufacturers. The metal sleeve in contact with the concrete is stainless regardless of the material of the threaded portion of the anchor. So that likely debunks my theory of scratching the zinc coating during the expansion process...