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  1. EDub24

    Pre-Engineered Canopy Reactions Forces for a Mat Foundation (Also includes equipment skids)

    I second this. For canopies wind uplift is critical. You'll need to make sure the mat/haunch has enough ballast to resist the uplift. You'll also need an estimate of the downward forces to determine the width of the haunch or the mat fdn thickness. You'll also need to make sure you have enough...
  2. EDub24

    Pre-Engineered Canopy Reactions Forces for a Mat Foundation (Also includes equipment skids)

    I wouldn't bank on this. In my experience I've sent drawings to them and they hesitate to spend too much BD time/effort to send reactions considering they're not guaranteed to get the job. They also don't want to take liability for sending preliminary reaction loads to be used on the foundation...
  3. EDub24

    ASCE Wind Loads - Enclosure and Internal Pressure.

    Full disclosure.I'm in seismic country so for most structures are controlled by earthquakes and I only do a cursory check of wind. With that said I think you could potentially have different enclosure classifications depending on which way the wind is blowing (pun intended). The enclosure check...
  4. EDub24

    Pre-Engineered Canopy Reactions Forces for a Mat Foundation (Also includes equipment skids)

    I agree with retired13. You need to know what type of lateral system it will be if you want to design the foundation. Or as others have said you can just design something ridiculously conservative and then trim it down during construction.
  5. EDub24

    Pre-Engineered Canopy Reactions Forces for a Mat Foundation (Also includes equipment skids)

    You’ll need to estimate the column reaction loads. In the past I’ve done some simple 2-D analysis of the frames to guestimate the loads and make clear the fdn would need to be checked based on the PEMB submittal. You should also know the general type of bldg. Typically for a canopy type housing...
  6. EDub24

    Open building wind loading (ASCE 7-16, Section 27.3.2)

    I'm in CA so I don't do much wind design as seismic almost always controls but have you looked a the diagram 27.7-8? It gives the different wind cases to consider including combing the different directions.
  7. EDub24

    Partially Buried Reinforced Concrete Tanks

    Yes, I do include the other modifications. My only question was in reference to the impulsive factor for an at-grade tank vs buried.
  8. EDub24

    Partially Buried Reinforced Concrete Tanks

    Yeah I've been using the lower R to date as well but wondered what other people did. Last I checked in the October ACI committee meeting they were still going over the public response comments for the upcoming ACI 350.3. The public response period was in the summer of 2018 so the updated version...
  9. EDub24

    Partially Buried Reinforced Concrete Tanks

    I'm currently designing a partially buried reinforced fixed-base concrete tank. When determining the seismic loads I am using ACI 350.3-06 with the modifications per §15.7.7.3 of ASCE 7-16. That section of ASCE 7 requires you to replace the impulsive response modification factor of ACI 350.3...
  10. EDub24

    Temporary Structure in Florida and California

    I think that's acceptable. Sometimes what I do is just design for the full wind/seismic loading. If it's OK I'm happy, if not then I would argue the need for a reduced return period. It sounds like your structure is pretty stout and lightweight so it might be OK. If you design for the full wind...
  11. EDub24

    Temporary Structure in Florida and California

    I haven't used ASCE 37 extensively but I know for wind they have a reduction factor based on the expected length of time the structure will be there. See section 6.2.1. The intent is to lower the return period from the ASCE 7 wind loads which I believe are based off a 3% chance of exceedance in...
  12. EDub24

    Temporary Structure in Florida and California

    I agree that engineering judgment is required but technically ASCE 37 isn't a referenced document in the building code (IBC, Florida or California) so it's not a guarantee that a bldg dept would accept it for a permit. If a permit isn't required then by all means go ahead and use it. The intent...
  13. EDub24

    Temporary Structure in Florida and California

    I’m not sure I’m on board with the use ASCE 37 in this case. I agree with the intent but this structure isn’t involved in a construction site. CBC section 3103 is for temporary structures in use less than 180 days. I think that’s what the OP should reference IMHO.
  14. EDub24

    Surcharge Load

    You should check out the NAVFAC design manual 7.02. Lot of good information there. I believe that’s where those graphs retired13 posted came from.
  15. EDub24

    Are process structures exempt from IBC code?

    I agree. I should have clarified that I was referring to structural items and not non-structural when I mentioned a lack of ethics. For non-structural I often turn to OSHA than the IBC like for stairs as you mention. Another common item is guadrails. IBC requires something like a 4" sphere can't...
  16. EDub24

    Vs30 Map for Determining Site Class

    I personally wouldn't use that map. I'm not a geotech but I would imagine there are a lot of variables in determining the soil shear velocity for a specific site. A map like that is too general for this purpose. It might work well when estimating earthquakes etc but it's not specific enough for...
  17. EDub24

    Are process structures exempt from IBC code?

    I work in the water/wastewater industry and a majority of the time the owners (usually cities, districts or agencies) don't answer to the building department so technically we aren't required to design to the IBC unless the client requests it. With that said we always design to the IBC and the...
  18. EDub24

    Design example or textbook - Reinforced Concrete Column design for axial, shear and torsion loads

    It should still be additive as WARose says. When you create the free-body diagram you 'move' the shear to the COG of the column and then add the torsion based off the eccentricity of the shear load. You design the column for the shear and axial load. Then design for the torsional load. Add the...
  19. EDub24

    Service Load combination for Tank design - ACI 350.

    I haven't used ACI 350-01 but I assume the 'S' factor is equivalent to the 'Sd' factor in ACI 350-06 §9.2.6 which is the durability factor. You should read the commentary but in summary this factor is used to reduce the overall stresses in a concrete member to better control cracking. The Sd...
  20. EDub24

    Service Load combination for Tank design - ACI 350.

    You keep referencing ACI 350 section 8 but I think it's been cleared up that you should be referencing Chapter 9 unless you mean to use Appendix C? Chapter 8 in ACI 350-06 is general considerations for analysis and design. The actual load combinations are in Chapter 9. Either way what you list...

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