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  1. jdcollins

    Steel idtification

    That's very likely going to be a W10x15. Used to have "B" beams that were "light" beam shapes. At some point they got enveloped into the W-shape family.
  2. jdcollins

    Steel Angle Question

    The first equation you post from F10-1 is for single single angles loaded along their length. The situation you have in the problem is for the bending of a single leg of the angle, which effectively behaves as a rectangular bar, which is controlled by section F11 in AISC. You'll see that the...
  3. jdcollins

    ASCE 7-16 -c&C Roof

    I think this is one of those cases where you truly have two different roof conditions. I think you use flat roof pressures for the flat roof and you use hip roof pressures for the hip roof.
  4. jdcollins

    Optimal girder setback (pre-engineered hip roof)

    I guess you technically can depending on how long your overhang is.
  5. jdcollins

    Optimal girder setback (pre-engineered hip roof)

    I've always used 7'-0". I've seen 7'-0" often, sometimes 5'-0", other times 9'-0". From what I've noticed, the steeper the roof pitch, the smaller the set back. This seems to be due to the fact that you can get a deeper girder truss "quicker" on a 5/12 pitch as opposed to a 3/12 where you might...
  6. jdcollins

    C&C roof positive pressure near parapet

    Not sure if this is acceptable per the code, but my interpretation of this condition would include the higher positive wind roof pressures (downward) on the area between the unit and the parapet when you are analyzing the wind in the direction right to left in your sketch (leeward parapet). When...
  7. jdcollins

    C&C roof positive pressure near parapet

    Figure 30.3-2A does not address pressures on the parapets, only the pressures on the roof. Essentially, if your parapet is 3ft or higher, your Zone 3 negative pressure just equals your Zone 2 negative pressure (or, Zone 3 goes away and becomes Zone 2). However, your POSITIVE roof pressures...
  8. jdcollins

    Components & Cladding for Partially Open Buildings

    In ASCE 7-22, partially open is included in those. My assumption is that they messed up and forgot to include it in ASCE 7-16. My tin-foil hat opinion: Partially open was added simply because we aren't comfortable labeling buildings that are THAT "open" as "enclosed." Technically, "enclosed" or...
  9. jdcollins

    Components & Cladding for Partially Open Buildings

    It's the same design procedure as for enclosed or partially enclosed, but with the partially open GCPi factors, which happen to be +/-0.18, same as enclosed.
  10. jdcollins

    C&C roof mechanical louver doors

    That's not how the wind load provisions work. This is likely being calculated assuming your mechanical room is a "Rooftop Structure" per ASCE, which forces you to use Sec 29.4.1 (ASCE 7-22) which, simply put, takes your design wind pressure at your main roof elevation and multiplies it by 1.9...
  11. jdcollins

    column spalling

    Agreed. I started seeing this a lot while doing threshold inspections on flat plate construction. They are smacking the column vertical dowels with a sledgehammer to either make the beam reinforcement fit or (after the elevated slab is poured) to make the column cage fit. When I've noticed it in...
  12. jdcollins

    Pre Loading Steel Beams

    I've done this once before, but no longer have access to the drawings/specs. That being said, the basic process was we determined how much we wanted to "pre-load" the beams. Agreed on 80% of the existing structure dead load similar to a post-tensioned slab. We used beam loading/deflection...
  13. jdcollins

    Collector Steel Beam

    My assumption is that the intent is for the connections on this beam to have standard bolt holes (as opposed to short slotted). If the contract drawings don't provide you with an axial force to design for, then I'd send the EOR an RFI. I'm assuming you're the steel connection engineer in this...
  14. jdcollins

    depression in composite slab

    I've seen similar things done fairly regularly with cast-in-place concrete decks. In past projects we've had a continuous concrete slab pour that extends out over a balcony. In the area of the balcony, the finishers will provide a 1/2" step and then slope from the step to the concrete edge. If...
  15. jdcollins

    Florida Building Inspection Law

    As far as I am aware, no new law has been signed in Florida. The state legislature could not agree between the house and the senate on the proposed recertification bill, and therefore the statewide building recertification bill died on the floor...
  16. jdcollins

    Open Web Floor Truss Identification Help

    This appears to be one of the "RedBuilt" open web trusses (joists) that may have been purchased from Weyerhaeuser. I've encountered these on a project before. You would probably benefit from contacting RedBuilt. When I contacted them once, they were actually able to locate the original account...
  17. jdcollins

    WF Beams and Bridging Requirements

    We've recently had to do a few projects with the exact same problem. A typical 5'-0" joist spacing with 1-1/2" deck becoming a 10'-0" beam spacing with 3" deck. I've always specified bridging angles. Bottom flange bridging for the in service uplift condition as well as top flange bridging for...
  18. jdcollins

    Nightmare Wood Project

    While I agree with DaveAtkins and phamENG about seeing if a double post can work, I'd also make sure you make it worth your time. Effectively, the contractor can install what you've required on your drawings, or he/she can pay you for your time to re-engineer and re-detail the design. If I can...
  19. jdcollins

    Help Identifying old roof deck

    That looks like a gypsum bulb tee roof.
  20. jdcollins

    Delaminating Glulam Beam Repair

    Sam, I don't think I agree with your approach on the calculations for the fasteners. The intent of the fasteners is to resist the slip between plies (as if you were adding a ply at the bottom to increase an existing beam depth). That force is a function of your shear, not your bending moment.
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