Steel Composite Beam and Deck Cold Joint

[SteelPE]

I have a project under construction that utilizes composite steal beam and deck (concrete slab supported by composite steel deck on steel beams with nelson studs). See attached photo.

For whatever reason, the contractor decided to pour a cold joint right at the edge of this composite beam. I am a bit concerned with the placement of this cold joint and whether or not the beam will develop proper composite action (not sure if I am overreacting here)..... and how to go about repairing this situation.

 

[jhnblgr]

What assumptions did you make in design? What was the effective width?

 

[SteelPE]

We did not run hand calculations on this particular beam..... but I am guessing, if I dug into everything the effective width would be much wider than the proposed concrete section with the cold joint.

 

[lexpatrie]

Either it needs to have shear transfer as needed to engage the other side of the concrete, or it needs to work ignoring the stuff past the cold joint.

At least it's not in the width of the beam.

And what do you kean we don't have calculations for this beam? That's not right action.

 

[SteelPE]

And what do you kean we don't have calculations for this beam? That's not right action.

We don't have hand calculations, but we did run this through a modeling software.... and, as suspected beff = 39"

I suppose we could just say the beam is no longer composite and reinforce the beam accordingly. Currently beam is W18x35 and needs to be a W21x44 if it were to be non composite.

 

[KootK]

I wouldn't reinforce. Rather, I would just set the next sheet of WWF in such that the crossbar was tight to the joint. Maybe a little light roughening if that could be accomplished with out messing up the finished surface.

 

[phamENG]

Is that a pour stop? Did the 39" width consider the fact that it only had a slab to one side?

 

[SteelPE]

Is that a pour stop? Did the 39" width consider the fact that it only had a slab to one side?

Yes, that is a pour stop... and yes, the 39" does account for the pour stop and the slab opening

 

[phuduhudu]

You could calculate how much shear transfer is required across the joint and then take a view as to how much you can get across the joint taking into account the reinforcement as well. I assume the pour stop is on a metal deck ridge so you are left with less concrete to transfer the shear.

 

[TRAK.Structural]

You could try to drill and anchor some #4 bars into the already hardened concrete with structural adhesive if needed for the shear transfer. Depending on how much space there is and how thick the slab is this option may or may not be do-able.

 

[JLNJ]

I'd check it as is. You have a nice compression block - no deducts for the metal deck flutes. Bump your concrete up to 6000 psi for this piece and see where it puts you.