The eccentricity should be a/2, or 1.75". That makes C=11.6.
Your 84 ksi bolt shear is wrong. You should be using 54 ksi (for A325 bolts, threads included in shear plane). That will give you 138 kips. Use a=3" and you'll get 139 kips.
Note that these tables do not check weld shear. The...
In the spreadsheet, the kdes values are the same as the kdet values. This seems odd. I would expect kdes to be less than kdet, like it is for wide flanges. I don't expect that channels are rolled to such a tight tolerance and consistency that the minimum and maximum expected values of k are...
On page 37, the ASD example says "Use Ta/(db+2b)", but the value used in the following box is Ta/g. I think that's where the typo is. The ASD example should say "Use Ta/g." Then on page 36, where they say to use the lesser of, it should read use the greater of.
I don't know why AISC makes...
If that's what the 15th edition says, it now has 2 errors. 0.5774*L is the correct value. Take the equation for Vx, solve it for x when V is zero, and you get L/sqrt 3. The error first showed up in the 13th edition manual. It was right in the manuals before that.
I think using U=1-xbar/L is a reasonable approach, with xbar equal to half the plate width like you show. You could also check the plate for combined moment and tension, where the moment is the force times half the plate width. With any luck the two methods will yield about the same results...
This Steel Quiz discusses the 38" limit and what an end-loaded connection is.
https://www.aisc.org/globalassets/modern-steel/archives/2014/03/2014v03_quiz.pdf
JAE, your example is incorrect. The 38" length applies to 'end-loaded" connections. In the example you describe, the load along the bolted connection is applied incrementally, along the depth of the beam web, and it leaves the angle and goes to the support incrementally, at each bolt row.
An...
Nor Cal SE, the AISC Specification does not apply to either of the connections you describe. Good engineering judgment and sound connections must be provided, of course. The AISC provisions may indeed be well and good, but they would be recommendations, not requirements, for these cases. "Not...
AISC Specification section J3 deals with high-strength bolted connections between two steel members. It does not apply to connections between steel and post-installed or cast-in-place anchor rods. That's why AISC calls them anchor "rods" and not anchor "bolts." Table 14-2 doesn't violate the...
SM3225 is looking for an AISC reference that deals with shear tabs with both shear and axial load. The connection engineer told him that AISC says you can neglect this axial load. Of course this is nonsense; SM3225 is asking for an AISC reference that states this.
AISC's Seismic Design...
Properly installed TC bolts do reach the full bolt pretension, making them appropriate for connections where pretensioned joints are needed. But TC bolts can also be used in snug-tight joints, even if the splines are twisted off. Some erectors prefer TC bolts for the ease of visual inspection...
Yes, the connection you describe, a shear tab with long-slotted holes, should have the bolts in a slip critical condition. There is moment on the bolt group, and the normal resistance of bolts bearing against the plate won't be achieved due to the long slots.
This is not documented anywhere in...
AWS says you're supposed to show the weld size on both sides. Weld size and triangle on one side, blank triangle on the other is common, but it is not technically correct. It used to be, I think many years ago, but it's not currently.
Your original question is, if there is a construction defect, and nobody catches it, can the building official come along years later and insist it be "upgraded," and if so, under what authority?
I would say yes, if there is a defect, and it is discovered, of course the building official can...
I've calculated the moment long-hand before, and I get the same answer as the equation. I haven't gone to the trouble of deriving the equation. Give it a try yourself and see.
