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  1. ProLuke

    Point load added to unknown existing beam with new column under point load

    To answer one question about how the existing concrete is performing - it seems in excellent shape; I did not observe any signs of failure. To answer a question about FRP - that is an idea I didn't think of yet, thanks! One issue about strengthening up the beams and column with FRP is we still...
  2. ProLuke

    Point load added to unknown existing beam with new column under point load

    Thank you all for the thoughts and comments. I did not think of the uplift on the existing column due to being so close - that is something to consider for sure, thank you. I did consider the idea of not messing with it, but our live-only load increases about 30% - well over the 5% allowable...
  3. ProLuke

    Point load added to unknown existing beam with new column under point load

    You are right - the 2700 lbs per foot is both live + dead (worst load combination in this scenario). Live load is only 920 lbs per foot. It does make sense that the dead loads area already supported and we would potentially only be suppporting the new 5,000 lb load plus the live tributary =...
  4. ProLuke

    Point load added to unknown existing beam with new column under point load

    Hello! This is the situation: An existing house with a concrete beam approx 12"x24" spanning 16 feet. The existing beam holds up approx 2,700 lbs/foot. We want to add a 5,000 lb concentrated load above the beam. We want to add a column directly under the 5,000 lb load. Does this column...
  5. ProLuke

    CFS Web Stiffeners at end bearing required when using clips to hang joist from its web?

    Thank you for your replies - if someone reads this later on, I wanted to follow up with what I ended up drawing: - I found the Clark Dietrich standard detail for E clips says to use a 7" clip for a 10" purlin, and the 7" clip does not have enough capacity. - I specified a Simpson SJC8.25 that...
  6. ProLuke

    CFS Web Stiffeners at end bearing required when using clips to hang joist from its web?

    Thank you for the replies - KootK your logic makes sense. XR250 - I would imagine that Clark Dietrich has accounted for this eccentricity to deliver the force as an almost pure shear to the web of the supporting member (that the 9 screws between the clip and joist act as a moment & shear...
  7. ProLuke

    CFS Web Stiffeners at end bearing required when using clips to hang joist from its web?

    Hello! I am designing a carport using cold-formed steel as the roof joists (1000S350-68 at 40" o.c., spanning 20 feet) that are hanging flush from back-to-back stud sections (1000S250-68 back-to-back spanning 10 feet between posts). I have used various software (Simpson CFS & AISIWin) that both...
  8. ProLuke

    steel frame - column to beam connection

    I have seen similar to option B in moment frames. See the photo - it has steel plates welded to the end of each beam, and they are connected at approx 45 degrees. You can’t see well in the photos, but the outside corner has the plates extended beyond the beams about 6”, and another set of bolts...
  9. ProLuke

    Fastening into End Grain of Laminated Member

    Hi Drew, I agree with you about not liking to screw into the end grain, but the wood code does allow it like you said with the reduction factor of 0.75. So I think you are right to just calculate the withdrawal and shear on the screws and find a screw that works. Personally I would pick...
  10. ProLuke

    SE Exam AASHTO Code

    Hi Imagine18, I am taking the test in April 2018 and am facing the same thing... don’t want to buy the new AASHTO code. Did you end up buying the new or using the older code? Did you pass? I am studying now using the NCEES provided practice exam and it seems like all the ASSHTO questions’...
  11. ProLuke

    Modeling Program ?????

    I use Risa Connection, and I really like it. It is purely for connections, so you enter the members you are connecting and the forces, the connection plates (if any) welds, bolts, ... and you get a 3D model to verify your inputs. You can export the views to autocad with labels for details. It...
  12. ProLuke

    ASCE7-05 6.5.12.2.1 gives huge pressures to design for, is this correct?

    I figured out what I was doing wrong to get such large pressure values using ASCE7-05 equation (6-17). Hopefully this can save someone the weekend stuck in the office I have had :) You are supposed to use + or - 0.18 for your internal pressure coefficient to determine the windward and leeward...
  13. ProLuke

    Potential Project sketchy?

    Hello, What I would do is make sure the building is at least as strong after the project as before - so if you're making a 3' opening in the wall, I would see what plywood was removed and what was the nailing pattern. Then I would calculate the shear capacity of that removed plywood and add...
  14. ProLuke

    ASCE7-05 6.5.12.2.1 gives huge pressures to design for, is this correct?

    Hello, I am designing a 5 story wood framed hotel building approx 53' x 180' footprint. I am ending up with large pressures to design my plywood shearwalls for, and no difference in pressure between interior and corner zones. Is this correct? Here are some details about the project: I am...
  15. ProLuke

    Light gauge steel bracing spacing for an open structure?

    Hello, I am trying to figure out how much bottom-flange bracing to use on a LGS roof with no ceiling attached. I am designing a car port that is open on all sides. I am in Houston, where I end up designing for 87 psf uplift. I want to use light gauge steel roof joists, with a corrugated...
  16. ProLuke

    PTI design equations for expansive soil moment and shear in grade beam

    Thank you Ericca! So it is correct that I don't need to convert any units? My Total load is 1165 plf on the perimeter grade beams. I am planning to do the grade beams 12"x24", so I use 24" for "h" The spacing across of the ribs is 12'. Using the PTI equation for center lift, I get 7.9...
  17. ProLuke

    PTI design equations for expansive soil moment and shear in grade beam

    Hello, I am designing to footings for a two-story wood framed house. The house has a rectangular footprint 20' x 60'. The soil is expansive clay. I am trying to calculate the maximum moment and shear in the grade beams during edge-lift and center-lift I have a soils report that recommends...
  18. ProLuke

    IRC 2009 Table 802.5.1 produces overstressed joists?

    Oh... so if I am using a non-snow live load, it would be considered a construction-duration live load, so for the calculations use 1.25 load duration factor? That would explain why I get 122% stress using 1.00 duration. Thank you all for answering my question! --Luke
  19. ProLuke

    IRC 2009 Table 802.5.1 produces overstressed joists?

    Please excuse my poor post... this is my first. Let me clarify: I am calculating for 20 PSF dead and 20 PSF live (no snow load) The span is 19'. The lumber is going to be Southern Pine #2. When I look at the IRC table R802.5.1 for roof joists with 20 psf dead and 20 psf live, at 24" O.C...
  20. ProLuke

    IRC 2009 Table 802.5.1 produces overstressed joists?

    For the 24" spacing... I'm using 20 PSF * 2' spacing = 40 PLF
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