AISC Steel Design Guide 1 Errors and Question - Base Plates

[gbuell]

I'm working through the large moment base plate design procedure in AISC Steel Design Guide #1 2nd Edition for anchor bolts and base plates, and I'm having some issues. The example problem given for this procedure contains some calculation errors that render the results meaningless, and when I try to just follow the prescribed procedure, I'm having a problem. Here it is:

The end of section 3.4.1 simplifies the equation for Y to Pr/qmax. Equation 3.4.2 says T = qmax*Y-Pr. If both of these things are true, then T will always equal zero. This doesn't really make sense as the entire point of the large moment base plate design procedure is that some tension will go into the anchor bolts. The design example at the end of the guide is useless because it finds T using incorrect numbers in the equations. Any ideas on the correct way to be doing this?

 

[gbuell]

Whoops, I think I've answered my own question. Y only simplifies to Pr/qmax at the boundary between large and small moment base plates - any moment larger than that boundary results in an e value larger than ecrit, so the quadratic equation for Y should use e instead of ecrit. Duh!

 

[nutte]

You have the First Printing of the Second Edition. You need to get the Second Printing (March 2010) of the Second Edition.

 

[gbuell]

Thanks nutte!