Anchorage in Circular Column 1

[TLycan]

Dear All,

Is there any paper or Ideas of calculating the Concrete modes of failure per ACi-318-Appendix D for an anchorage in the face of a circular column. What I mean by face NOT in a circular cross-section as anchors protruding from concrete pedestal; it is a beam connected to circular column.

thanks in advance

 

[thaidavid40]

A sketch of your proposed connection details would be of great help here, as the answers will greatly depend on the details.
Dave

Thaidavid

 

[TLycan]

Dear Thaidavid40,

attached is a sketch for what I mean

 

[CBEngi]

From your sketch I notice one thing off the top of my head. Why wouldn't you pass a plate(s) through the concrete column and connect the two beams directly together. This would take care of any tension force problems locally.

If its a shear connection your worried about, I would think about using epoxy anchors, or anchors that pass right through the column from plate to plate. Really these bolts could take any tension requirements also (if sized right).

 

[thaidavid40]

@CBEngi's points are all well taken. Through plates or bolts would have to be carefully coordinated, as your sketch seems to show the beams on slightly different radial alignments (not directly across from each other. I have also seen a short length of heavy steel pipe section, with internal headed studs welded radially, cast into the concrete column section, with proper clear cover. The steel tabs and gussets were welded to this pipe section, and project out to the beam connections beyond. You may need to wrap the projecting tabs in a thin layer of expansion joint material, to provide working clearance around the surrounding concrete (to prevent surface spalling of the column at those points).
Good luck,
Dave

Thaidavid

 

[KootK]

Is there any paper or Ideas of calculating the Concrete modes of failure per ACi-318-Appendix D for an anchorage in the face of a circular column.

I don't know of any. However, I believe the model shown below to be a rational extension of the Appendix D provisions to curved surfaces. Obviously, the gentler the curve, the better.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.