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Recent content by dold

  1. dold

    Diaphragm Tie Plate

    The 3/8 tie plate is there specifically because it is in line with a braced frame. I.e., a collector. PL 3/8x4 Gr. 50 (for a small-ish beam) is good for about 50k ASD. That will hammer a bolt group for smaller beams. Even with bigger beams you'll end up with several columns of bolts in the...
  2. dold

    Tall building calculation report

    https://portal.ct.gov/-/media/csc/2_ems-medialibrary/westhartford/ishamrd/verizon/emver155190205responsetoincompletepdf.pdf This should suit your needs
  3. dold

    Joist seat forces in Multiple Span Joist Construction

    Collective chord behavior. https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1044&context=aen_fac I made a spreadsheet for it ages ago to prove to my boss that our chord sizes were absurd in some of our warehouses, but never really used it. Because, well:
  4. dold

    Importance Factors Before The IBC

    I don't have an answer to your question directly but... My first step when working with older buildings is to file a FOIA (sometimes FOIL) request with the jurisdiction where the building is located. Sometimes they have nothing, sometimes they have a treasure trove of drawings and as-builts and...
  5. dold

    Lateral Torsional Buckling of Thin Beam

    Still seems to me like these fin things are simply going to get squashed right at the edges of your support. The "beam" (fin thing) will deflect upward ever so slightly and at that point all of your reaction forces will be concentrated at the edges. I probably wouldn't approach this as a...
  6. dold

    Solution for Beer Tank Installation in an Urbanization Project Near a River

    Many times we will spec concrete encased duct banks for road crossings. I.e., flowable fill. Contractors often fail to properly compact backfill which causes bumps and dips in the road crossing. I'd probably recommend running several large conduits (ducts) under the road and the actual "beer...
  7. dold

    2 span continuous - Always a 25% increase under UDL?

    I'm guessing the "put in a footing" option has already been ruled out as a possibility?
  8. dold

    Lateral Torsional Buckling of Thin Beam

    I think you got your b and t backwards for moment of inertia since it will be buckling in the weak axis direction, no? b = 0.6", t = 0.02". Peuler = 30 lbs, at 2.5ksi. Either way, I don't think we have an accurate picture of the problem statement. Is this "assembly" like some sort of heat...
  9. dold

    Determining the drift of a structure with a flexible diaphragm (in RISA 3D)

    Ditto. A firm I worked for would use a 16" plate + ~C8 channel toed down as a chord. We'd put a 3' sheet of roof deck between the tilt wall and the chord. 1. For extra capacity in long warehouses, 2. for flexibility around bumpouts and such in the wall line. We'd still have an edge angle but it...
  10. dold

    Lateral Torsional Buckling of Thin Beam

    I don't see how 20mil sheet could handle 50 lbs, let alone 5000 lbs? That's just a hair thicker than a 25 gauge drywall stud.
  11. dold

    Concrete Masonry Bearing Walls 12" to 8" transition

    I'd provide at least several layers of ties under the bearing at a minimum. A little mini-column in the 12" block. Just to keep the thing from blowing apart like you say. 300psi is still pretty high. Maybe look at an embedded grillage beam - WF or HSS maybe, stocky. That sort of creates a hinge...
  12. dold

    Concrete Masonry Bearing Walls 12" to 8" transition

    I've seen this overhanging bond beam detail before in some retail strip malls near Seattle. 1970s-1980s construction. But they were wood parallel chord roof trusses spanning ~40'-50' so maybe they needed the extra bearing. And I believe it was an exterior wall with parapet - trusses on one side...
  13. dold

    Ordinary Moment Frame Connection Upgrade

    Existing connection, people. Hell of a lot easier to add stiffeners than disassemble the structure and cut the plate off, IMO.
  14. dold

    Design Load for a Door

    Did they use a bomb to make the rough opening or something? Surely some wood blocking could make up the gap? How much bigger is the R.O. than the frame?

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