Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations MintJulep on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. DaveAtkins

    Ponding Load

    Good question. I think I would use the higher E value, because ponding is associated more with deflection than stress.
  2. DaveAtkins

    Ponding Load

    If AISC Appendix 2 is used to check ponding, it includes provisions for open web steel joists. I have never heard of anyone being concerned about ponding on a roof constructed of wood rafters. I suppose it is possible, but I think the spans are generally shorter so deflections are smaller.
  3. DaveAtkins

    Ponding Load

    I will agree with that, ChorasDen. If you account for the additional water due to the deflected shape of the members, then I suppose you don't have to follow AISC Appendix 2. But it is an iterative process. The deflected shape allows a little more water to accumulate, which causes a little...
  4. DaveAtkins

    Ponding Load

    lexpatrie, The excerpt you posted does not talk about ponding. Theoretically, a roof could be OK for "8.2 DESIGN RAIN LOADS" but still not be OK for ponding.
  5. DaveAtkins

    Ponding Load

    Designing for blocked drains and designing for ponding are two different things. What you have described is designing for blocked drains, but not a typical ponding check. A ponding check verifies that the members you choose are stiff enough so they will not progressively collapse due to water...
  6. DaveAtkins

    Beam Reinforcement Calculation

    I would use the shear flow formula, VQ/I, to determine the load per lineal foot in the weld. Then design the weld accordingly.
  7. DaveAtkins

    Eccentric Pad Footing with Tie Bars?

    There is a moment which must be resisted by the slab-on-grade. There will be an upward reaction at the center of the footing, not lined up with the downward wall load. The wall load times this eccentricity is a moment which must be resisted by the slab. The slab will need to be reinforced...
  8. DaveAtkins

    Roof Collapse in Madison Wisconsin

    Update - the collapse was caused by blocked drains. I think the takeaway is if your building does not have overflow drains or scuppers, you need to check the roof drains on a regular basis.
  9. DaveAtkins

    Roof Collapse in Madison Wisconsin

    Right. And they may not have had overflow drains. That seems to be a more recent thing.
  10. DaveAtkins

    Roof Collapse in Madison Wisconsin

    https://www.fox6now.com/news/woodmans-roof-collapse-madison-video I am guessing a ponding failure. I lived in Madison many years ago, and I believe this is an older building. Roof may not have been designed for ponding.
  11. DaveAtkins

    Shelf Support Steel Angle Fastened to Cold Form Exterior Stud for Brick Veneer

    Because there will be tension in the bolt, it will bend the stud flange. I suppose you could make a bolt work if you used a plate washer to prevent the flange from bending, or if the load is light enough, perhaps justify the flange bending.
  12. DaveAtkins

    Shelf Support Steel Angle Fastened to Cold Form Exterior Stud for Brick Veneer

    I have never used bolts to connect a brick veneer shelf angle to cold formed studs. I have always used welds. It is best to weld vertically, to the web, not horizontally, to the flange, because the flange can bend due to the tensile component of the moment.
  13. DaveAtkins

    Combined footing problem

    The weight of the foundation multiplied by the distance from the toe of the footing to the centroid of the footing must be greater than 1.5 times the overturning moment caused by the frame. Or, you can check 0.6 times the weight of the foundation against the overturning moment.
  14. DaveAtkins

    2x10 Floor Joist Hung from Ledger

    That detail looks fine to me.
  15. DaveAtkins

    Birdsmouth I-Joist Cut

    I would share the photo with Boise and get their recommendation.
  16. DaveAtkins

    Design Advice for Sheet Piles Supported on Steel Columns

    Why are you transferring the sheet pile load to the catwalk columns? I think they should be treated separately.
  17. DaveAtkins

    What metal deck connections do you use for K joist?

    I just checked online - I guess gunpowder driven pins are still an option! Sounds dangerous to me[cannon]
  18. DaveAtkins

    What metal deck connections do you use for K joist?

    Early in my career (almost 40 years ago), I think they were called POWDER driven fasteners, because I believe there was gunpowder involved.
  19. DaveAtkins

    Snow drifts against low roof parapet per ASCE 7-22

    I think you should use lu = 344 feet for the low roof parapet. I don't know of any literature or code that allows you to reduce the upwind length of roof due to interruption by a parapet.
  20. DaveAtkins

    What metal deck connections do you use for K joist?

    I used to specify puddle welds, but now I always specify screws. Seem a little more foolproof to me.

Part and Inventory Search

Back
Top