Venting and Drainage holes in Galvanized HSS members.

[Day_Reddy]

On a steel shop drawing I am reviewing the fabricator has placed venting and drainage holes on the side of the members. See attached images of the Column resting on a Beam and the Beam section with holes in it. I do not have a base plate attached to the column, the column gets welded directly on top of the Beam. See attached recommendations from the American Galvanizers Association on the max size of the hole and its location. From what I understand from these recommendations is how to pick the size of the hole and how to place it at the ends either in the base plate or the cap plate. Has anyone ever seen holes placed on the side of the members and not on the base plate or the cap plate of the members.

 

[dauwerda]

Holes on the side (I commonly hear them referred to as rat holes) are a typical solution for venting/drainage (as is on the cap plates). Obviously, you would need to double check the strength of the section and weld to make sure it is acceptable.

 

[Day_Reddy]

dauwerda, that was my concern too. The column is sitting on the center of the beam and I have lost so much material at the center. I did not design this so I am not sure about the stresses in the beam and I haven't yet checked if the member is good enough with holes. But if the fabricator insists on having so many holes, I might have to end up checking the beam with lower section properties.