column spalling

[struct_eeyore]

I have a number of columns that are exhibiting spalling immediately below bearing. As far as we can tell, these are superficial and don't progress beyond reinforcement. The beams above have not yet been loaded yet. The spalls occur on random sides of the columns along any one grid line. Other than improper spacing and cover of ties, what could be the cause? Some of the columns also have horizontal (possibly shrinkage?) cracks, which I've never seen.
edit: title

 

[SWComposites]

What is the stuff that looks like foam?

 

[struct_eeyore]

I want to say that's insulation foam that the contractor used to to fill in gaps in the form work.

 

[HTURKAK]

Apparently , the column and the supported beam casted separately and my opinion is , the spalling occured during dismantling of the forms and scaffolding .. Poor workmanship..








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Make it do, or do without.

NEW ENGLAND MAXIM

 

[hokie66]

Yes, that type chunk separation at the top of columns is a result of abuse during construction. An indication of very poor workmanship.

 

[struct_eeyore]

So, additional information is available - see new photo. Would everyone be in agreement that the horizontal cracking looks like plastic shrinkage? I'm thinking the spalling at the top was aggravated by the excess separation as well. A portion of these columns and beams form a portal frame, and I'm concerned about how the weakened concrete will act when loaded in bending at the joint - is there a proper recommended repair with something like this?

 

[Aesur]

It appears you are located in Florida, if the spalling went to reinforcing, I would be worried about saltwater intrusion and may consider some kind of wrapping the column to prevent that at this point, something like FRP, which it's probably overkill from a strength consideration (assuming there wasn't a design issue to begin with), it would be good for protecting the rebar.

 

[jdcollins]

Yes, that type chunk separation at the top of columns is a result of abuse during construction. An indication of very poor workmanship.

Agreed. I started seeing this a lot while doing threshold inspections on flat plate construction. They are smacking the column vertical dowels with a sledgehammer to either make the beam reinforcement fit or (after the elevated slab is poured) to make the column cage fit. When I've noticed it in the past, I make them chip out around the damage until they reach sound concrete and then repair using a high-strength repair mortar. It usually stops happening after they've completed a few of these repairs.

 

[Tomfh]

That horizontal plastic cracking can happen when the beams poured too soon after the column. The column is still shrinking/settling

 

[hokie66]

Yes, it is a form of plastic shrinkage. Probably more correctly described as plastic settlement cracking. It is due to inadequate compaction of the column concrete. The concrete below the crack settles, leaving that above suspended on the reinforcement.