Reinforcement Lap zone in Column as per ACI Code 2

[UsmanMaaz155]

Greetings Engineers,

I am Planning Engineer with contractor firm currently working on high rise building. We are facing an issue of lap location in columns. After raft construction exposed lap length of columns was more than design (200mm more) our team prepared steel for basement with reduced cut length to avoid wastage. Now lapping it 200mm above raft S.S.L (Structure Slab Level). is there any ACI code which give this permission?

 

[r13]

There is no such permission, but provides splice length is met, you should be fine. I suggest to stagger the splices though.

My question to you is, why there is extra length, a fabrication mistake, or mistake in construction?

 

[rscassar]

No issues with moving lap location 200mm above raft SSL. Codes generally have a minimum number of tie sets required over the spliced laps and extra ties at bar crank locations. If these locations have moved on the column then tie requirements will need to follow suit.

Extra 200mm sounds good, it's when reinforcement is scheduled short is the headache.

 

[hokie66]

I would say your "team" used false economy. Now you have to support the cage without being able to stand it directly on the slab.

 

[phamENG]

I'd go back to retired's question. Why are they standing too tall? If they were fabricated correctly, that means you probably don't have sufficient embedment in the raft and you have a much bigger problem.

 

[BridgeSmith]

I'll add my voice to to warning voiced by retired13 and phamENG - FIND OUT FOR CERTAIN WHY THE BARS ARE EXTENDING OUT TOO FAR BEFORE GOING ANY FURTHER! In my experience, mistakes in fabrication of the bars is a very rare occurence. If the embedment into the raft foundation is not per the design, the results could be catastrophic for a high rise building. Make sure it's right before the columns are cast.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[JLNJ]

You need to go ask the Engineer of Record what to do. Why are you asking random people on the internet such critical questions?

There are a million factors to consider. This forum, while full of smart people, is just guessing as to what might be the proper course of action.

 

[UsmanMaaz155]

@JLNJ will definitely consult with The Engineer, i was just asking about ACI code if code support or not. Thanks

 

[dhengr]

Some generations ago, a ‘reinforced lap zone’ was called a chastity belt. ACI is certainly stretching the bounds of its coverage when they start getting involved in these areas of social intercourse. Damn, these codes, they are truly ever expanding in their involvement. Pretty soon they will probably come out with a little pill to make older rerods stronger and stiffer.