Its tough to say what I’d actually do in the situation, but I think the right thing to do is:
Write a letter to the AHJ, copy the contractor and the owner. State that you have evidence that the building is not being constructed in accordance your plans and specifications. You requested the...
@lexpatrie
I agree with you on the ETABS GUI. I’m never quite sure if ive selected a member or not. It also crashes frequently. I’m a RAM elements fan myself but its not quite as powerful for building design.
@jayrod12
Good call. It’s always good to verify with a hand calc when trying...
- Single story building, 150'x200'
- Vertical system: Steel roof deck, bar joists, wide-flange girders, HSS Columns
- Lateral system: steel roof deck diaphragm, vertical braced frames (R=3)
With windows across the front wall, I planned to shift that line of bracing back a bay to avoid a...
Was there anything in the quality assurance section of the spec (I think part 1) requiring submittal of signed and sealed calcs?
Such a requirement should have been in there, though I’m not sure if what’s legally required. Is an 80’ gangway just a product?
Design documents? You’re lookin at ‘em. Hopefully the civil engineer who sealed this drawing specified (either on this sheet or in a spec) that the gangway needed to be designed by a licensed structural engineer.
That looks like a toe kick to me. The drawing for the 60’ gangway uses the bottom chord as the toe kick, which only allows room for a 2” deep cross member. The separate toe kick we see here is a better design.
Bugbus,
Please don’t stop your ramblings. I’m curious, what happens when you change the following parameters in your model?:
Cross girders from 6x3 to 2x1 1/2
3x3 top chord to 3” pipe
165lbs/person to 200lbs.
Also, what is the natural period of this thing?
Apparent cause:
Failure by buckling of pony truss due to grossly inadequate 2"x1 1/2" horizontal deck brace.
Root cause:
Lack of enforcement mechanism to prevent "manufacturers" from practicing engineering without a license.
Remember this was likely "pre-engineered". In other words NOT...
I’m working on a high-bay industrial building with a bridge crane sitting on laced columns. Strength-wise, relatively small sections work, however, AISC DG7 recommends limiting the inward movement of runways toward each other to 1/2”. This results in extremely heavy column sections, since...
Regardless of the number of bolts, there will be moment due to the eccentricity between the bolt line and the face of the embed. If you can get it to work, I would use a regular 2 bolt shear tab connection. On the beam side, you can weld the tab to a cap plate on the end of the HSS.
XR250,
The joists are all notched, so there's no way I could get a hanger in without cutting out the ledger entirely.
Bridgesmith,
You don't think putting (10) nails in the end of a notched 2x10 is too much? I guess I could make a mock-up and see what happens.
I recently had my deck rebuilt, and the contractor used 2x2 ledger strips instead of hangers to support the joists (2x10s @16”, 14’ span). To my surprise, my jurisdiction still allows this inferior detail. After spending so much money, I hoped for something truly robust and was wondering what...
This article from WBDG agrees:
Link
"Harsh exposure conditions from exposure, moisture, thermal effects, weathering, and traffic often reduce these systems serviceability at a rate even surpassing that of parking and bridge deck slabs"
I also found a paper showing reduction in punching shear...
I think we're all having a little trouble connecting the collapse of the pool deck to failure of the building columns. There must have been some sort of horizontal propagation of slab failure, leading to punching shear failure at the building columns due to unbalanced moments. This then...
I have family in an old low-rise condo down there. One of the buildings near the water was settling badly, and they reached out to a foundation repair contractor. I then received a call from one of the board members, who thought their proposal of four helical piles was way too many and they...
The lack of ductility here is truly striking.
I re-watched the video and it doesn’t look like a “pancake” type of progressive collapse. There’s a loss of support of one side the building which then radiates through the rest.
Regardless of what caused the loss of support, the structure...
A while back I brought up this issue to my colleagues and got a lot of strange looks. The typical practice was to leave stairs out of the structural model, because they will suck up load and fail the stringers in compression.
I replied that in reality the structure doesn't care how you've...
Thanks for the response HTURKAK. I'd prefer two separate platforms as well, but there's other equipment on the roof so space is a concern. Also, the equipment is not actually a condensing unit, so the stacked configuration won't cause problems w/ operation.
I'd also prefer a simple connection...
