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Recent content by straub46

  1. straub46

    Flush framed shear connection for shallow WF beams

    Try an extended shear tab connection? Could probably fit multiple vertical rows of bolts if needed.
  2. straub46

    Achieving 10mm crane rail support deflection limit while not overdesigning the column and footing?

    I think the lateral deflection you're trying to hold at 8m is unreasonable. That's L/800 of the column height. The beams that support the rails are generally only designed for L/800 vertical deflection and usually L/400 lateral deflection. But that's for the beam itself, generally the column...
  3. straub46

    Effective Wind Area - Stud Wall with Parapet

    Just FYI, PEMB manufacturers, or at least the major manufacturer I worked at, would not use the full length of the purlin to determine trib area. They would use the frame spacing x purlin spacing to determine tributary area on purlins. Wall panel pressure is girt span*panel width. i.e. 100 ft...
  4. straub46

    PEMB Shear Breakout

    I am the former engineer. I reviewed and sealed drawings in 5 states. That time working there has vastly helped me now that I'm back in the consulting world.
  5. straub46

    PEMB Shear Breakout

    As an FYI for #3, the PEMB engineers assume all the anchor bolts work in shear. They also only provide a standard hole for the anchors (not oversized), hence why they don't spec or call out plate washers. Source: former engineer for one of the largest PEMB manufacturers in the states.
  6. straub46

    PEMB Splice Modification

    The column reinforcing plates will interfere with the building girts if they extend past the outside flange. Those inside of the girts are generally flush with the outside of the column flange.
  7. straub46

    Lateral Loading for Fall Arrest Gantry Beams

    Fall arrest loads are required to be applied in any direction. Use the 3.6 kips for lateral. I would probably apply them at the same time.
  8. straub46

    Unrestarined Cold Form Design for Monoslope Roof

    PEMB manufacturers do usually add purlin bracing when using standing seam roofs to help with flexural capacity of the members. You can find erection details for Nucor (one of the large PEMB manufacturers) online. While sizes aren't listed, it can be a good starting point look at how the system...
  9. straub46

    Is additional weight of installing rubber roof tiles a concern?

    The IEBC (International Existing Building Code) says reroofing material 3 psf or less is acceptable for Alterations of existing buildings (generally without need for analysis). Your 6 psf is double that allowable. You should have it checked by your engineer. Go Bucks!
  10. straub46

    Multi-Span Frame with Multiple Cranes

    The snippet below is from a Crane Design Guide by CISC. The lateral side thrust is either 100% of one crane, or 50% of multiple. I've always limited it to 50% of two cranes; as you said, it's unlikely you'll be getting side thrust on a single column bay from that many cranes at one time. I think...
  11. straub46

    Fatigue Loading on Simple Shear Connections

    Are you concerned about the runway beam or the beams that support it? I would have no qualms with a roof beam having a simple end connection that's supporting an underhung crane. Were the moment connections provided for stiffness/provide a lateral load path? Go Bucks!
  12. straub46

    Fatigue Loading on Simple Shear Connections

    A prime example of why more information = better answers. For crane systems, you should be looking at some kind of bearing connection at the end of the crane beams, whether they sit on a bracket off a building column or an independent column. Holes are a major stress concentration area; I don't...
  13. straub46

    Crane Wheel Loads (Impact etc)

    Review the loads. Crane design assumes that the hoist, trolley, and crane load goes to one side (the hook is all the way on one side of the crane), and the bridge weight is evenly distributed. So for the example, the load per side is 57.2/2 + 40 + 10.6 = 79.2 kip. 79.2 kip/2 = 39.6 k/wheel. The...
  14. straub46

    Small Cantilevered Platform

    For platforms that small, make sure whatever lateral load you use is enough to cover the guardrail lateral force too. Usually that's not an issue, but if my conversion is right the 1 kN is just enough to cover the guardrail requirements here in the states. Go Bucks!
  15. straub46

    Trying to explain to non-engineers that it may be OVERKILL, but it is NECESSARY

    A lot of the other engineers here have given good advice on how to handle the situation. In one of your other threads you said you work for a construction company. I feel like pointing out the liability the construction company would have, especially if they're doing the design acting as an EOR...

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