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RE: Anchor in Bending

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Harold Sprague
 
>>The only thing that would have to be added is the interaction of shear and tension on the bolt.<<
 
Example 5 that you refer shows base plate.  Industry standard is to provide oversize hole in base plate and also grout under the base plate.  This will introduce bending in the bolts.  Bending of bolt is is totally ignored in this document except in Section A6.1.3 which states that when grout pads exists, reduce steel strength by 20%.  There is no commentary provided for this section.  The seminar that I attended lately, it was mentioned that this was done to account for bending in bolt.  However, there is no justification given to arbitrarily reducing strength by 20%.  There is no limit on the size of the grout pad, i.e., 1" or 1-1/2" or 2" or whatever.  Assuming a typical job with 2" base plate and 1-1/2" grout, there will be 3-1/2" eccentricity on the bolt.
 
Except for minor shear, bolts are useless to transfer shear in base plate situation and thus the example and the document should be used with caution for real use except for welded studs to the plate.  You may want to refer to Practical Design and Detailing of Steel Column Base Plates, AISC Steel Tips, July 1999, Section 4.4 for further discussion on this subject.
 
 
Satish