Column Misalignment..

[MIStructE_IRE]

Hi,

I’m currently in the middle of a project with an astonishingly poor concreting crew.. We’re halfway up the RC frame and now I’ve found out that they’ve built one of the columns off-plumb and off position.

I’ve reviewed their surveys, checked the P-Delta effect and it overstresses the column by just over 10% which I’m not happy with.. The other problem is they now have 2 flat slab levels poured above this!

My initial feeling is to perhaps increase the column area and then wrap the column in GFRP. Anyone had anything similar happen on a site?

 

[racookpe1978]

Which floor is the bad column in?
How many total floors?

When will the crew begin ripout and re-form and re-cast?

 

[MIStructE_IRE]

8 storeys. This is on level 3..

With 2 levels of flat slab above I’m concerned that replacing the columns (which I’d love to do!!) would actually do more harm than good.

 

[Agent666]

What limit states do you fail for the column, and what load cases? Is it gravity or lateral loadcases?
Is the 10% over state a flexural/axial interaction, confinement or shear issue, etc?

Wrapping in GFRP would typically only increase the confinement and possibly the shear capacity, but wouldn't address any moment capacity issues for example?

Is there possibility for redistribution with some minor level of yielding?

Have you already considered the full effect of any cumulative live load reduction? This could bump the load to a level that makes things work?

I'm assuming the out of plumb is greater than the code limits, which are already factored into the design capacities?

Have you specifically modeled the out of plumbness, as globally it may tend to distribute the forces differently than a simple axial load times the eccentricity and adding this to the previous design demands.