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Recent content by GearsNsparks

  1. GearsNsparks

    Rectangular Connection Element: Interaction Equation Valid for Compressive Loads?

    I was wondering if I had combined in-plane shear, in-plane bending, and compression axial loads on my connecting element, if this equation was still valid or if it was only valid for in plan shear + bending + tensile axial loads. Additionally, does that extend to Doswell's general equation (67...
  2. GearsNsparks

    Rectangular Connection Element: Interaction Equation Valid for Compressive Loads?

    Looking at the interaction equation for rectangular connecting elements in AISC 360 - Equation 9-1: Mr/Mc + (Pr/Pc)^2 + (Vr/Vc)^4 <= 1.0 Is this equation valid for axial compression loads Pr/Pc)?
  3. GearsNsparks

    Overstrength and Nonbuilding Structures Not Similar to Buildings

    Thanks Josh. Reviewing section 12.10.2: Collector elements, I interpret that to include any connections along the seismic load path need to be designed for overstrength factor. Does this also include the members connected by the connection elements?
  4. GearsNsparks

    Overstrength and Nonbuilding Structures Not Similar to Buildings

    I'm trying to figure out where (and if) Omega gets used when designing steel members and connections for non building structures not similar to buildings (Table 15.4-2). Does it only show up in the foundation design? A couple items for tanks and vessels are called out for section 15.7.3.a, but...
  5. GearsNsparks

    VFD and Locked Rotor Torque

    So if I'm sizing a motor for a conveyor with a large hopper on the end, it needs lots of starting torque until the material flows (transitions from static friction to kinetic friction) at the hopper and not so much once the belt starts moving. Should I size the motor based on 150% of name plate...
  6. GearsNsparks

    VFD and Locked Rotor Torque

    So to achieve the locked rotor torque value on start up, a VFD with the 1-2 second characteristic of 200% nameplate torque is the only method or is there another common alternative?
  7. GearsNsparks

    VFD and Locked Rotor Torque

    Does a motor starter/soft start achieve the DOL starting performance (locked rotor torque) shown in the manufacturer performance chart or is that a different behavior as well?
  8. GearsNsparks

    VFD and Locked Rotor Torque

    Howdy, If a 20HP NEMA B AC induction motor has a locked rotor torque of 200% of full load torque, would a typical VFD be capable of developing that locked rotor torque condition at start up? The current is 600% of full load current at start up according to the speed vs current curve chart. Is...
  9. GearsNsparks

    Steel Connection Design: Gap Between End of Beam and Column Flange

    Ahh roger that T_Bat. Looking at AISC part 10 page 84. Thanks!
  10. GearsNsparks

    Steel Connection Design: Gap Between End of Beam and Column Flange

    I'm pretty sure there are no clips on the beam web. Uploaded the best picture I had from the site visit. https://files.engineering.com/getfile.aspx?folder=94914063-4356-42ef-8f8e-0d45841f810c&file=bracing_question_site_pic.png
  11. GearsNsparks

    Steel Connection Design: Gap Between End of Beam and Column Flange

    Howdy, I'm looking at a bracing connection for some existing mining equipment structures. There is a nominal gap of 1/2" between the end of the beams and the connection to the flange of the column. Is this a common practice? Is it intended to help with manufacturability (getting the columns...
  12. GearsNsparks

    Geometrically symmetric struts with balanced vs. unbalanced loads on a column

    1. When designing columns with symmetric struts attached (see attachment) and assuming the tributary span A = tributary span B, do engineers still design for a shear load imbalance on the column due to fabrication imperfections? 2. When tributary span A > span B, is it reasonable to assume...
  13. GearsNsparks

    Comparing Brace Configurations

    Sorry for the late response; this board posts quickly. The lateral loading is bidirectional. They are normal concentric brace frames. The customer is fine with the looks of either configuration. I'm leaning towards B.
  14. GearsNsparks

    Comparing Brace Configurations

    I'm looking at two brace configurations and I don't think one has greater capacity than the other. See the attachment: Is there a reason why someone would design for style A instead of B? Does it come down to fabrication or...
  15. GearsNsparks

    Connecting to Wide Flange Column Flanges

    When modeling a member connection to the flange of wide flange columns, do people typically make a rigid link perpendicular to the column and half the column depth to impart the moment do to connection eccentricity?

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