52 Inch Lap Splice For 2 #5 Rebars In 8 Inch Block?!

TWOM JDuran

Morning everyone, this is my first post on the forum hopefully this isnt something that has been discussed over and over because I have searched and not been able to find any information close to what I'm looking for.

I am a superintendent for a construction company that seriously underbid the amount of rebar in a job (by assuming there was only 1 rebar per cell). We don't question that we made that mistake, but the real situation is this. On the plans, it has a rebar lap schedule that calls for 26" lap splice where there is a single rebar in the block. No complaints or doubts there. The same schedule also shows that in places where rebar are doubled (#5 E.F) it calls for 52" of overlap. Now, I don't see any reason to DOUBLE the lap if there is DOUBLE the rebar in the cell as is. Essentially working 6 pieces of rebar into some cells because of the required overlap and seriously slowing down the process of laying the block because we basically have to tie a 6.5 ft pc of rebar 4.5 feet down and work with 2 ft before repeating the process.

Here is my question/request(s):

Is there any information that I could present to the company to show them that that (and this is just my rationale): Since the lap schedule calls for 26 @ 1.... then 26 + 26 @ each rebar makes for a 52 inch lap?

Maybe there is an easier way of doing the block work also, we have only reached the 7th course as of today anyway... So if there is a technique that we could use to save any sort of material what is it?

I was thinking about maybe putting clean out holes at the very bottom and @ 52 inches, building the wall 9-10 ft then pushing the rebar down the cell and tieing it to the base and filling with grout. But I have my suspicions that inspectors would have a field day with that.

My location is in GA, there really is no hurricanes or anything that causes much damage so I'm having a hard time seeing why this building is being built our of 70% rebar and 30% block...figuratively speaking.

Lengthy post, I'm sorry but I have searched and read many websites and posts without any answers.

__________________
Mistakes of a rookie

19kevin56

I have just bid two jobs here in Florida with the exact same situation - single bar cells lapped 48 diameters and two bar cells lapped 72 diameters. It may be a seismic design issue on your job. As long as the cross-sectional area of the bars does not exceed 6% of the cell area, there's not much you can do. In your case, the total bar area at the laps is about 5% of the cross-sectional area.

The solution you propose is called high-lift grouting and is an accepted practice. The inspectors should not get heartburn over it unless they aren't familiar with it. Have your office get you a copy of the ACI 530 code for reference. Georgia is a "530 " state.

Regards

Kevin

TWOM JDuran

Perfect. Thanks for your help. I'll be on here often I'm sure.

__________________
Mistakes of a rookie

tkle

You shouldn't have to tie it at the base. Tie it to your horizontal. Use longer pieces and use open ended block,"H" or"A" shaped block.

Chris Johnson

52" seems even excessive to me

<---- See my location...it's a rumbling earth around here

If they won't switch there is a clip you can install in the bottom dowel and once you get to the top place your vertical in and it will lock it in (You need a mirror or flashlight to do this)

Another trick allowed in pour in place walls is to use a piece of 2" steel pipe usually 2" high, drop the vertical bar into that to keep the splice in place during the pour...don't know if the cell of CMU's and the slump of the grout will allow this.

__________________
Chris

TWOM JDuran

I found common ground with the contractor on the job, we both agreed that the 52" splices are not only ridiculous but also slow down production significantly, (and since they are already behind because of lackluster slab pouring) he agreed to bring the laps down to 26 inches. But I guess there is always a solution. This was done "under the table" without really anyone knowing, in a no harm no foul fashion.

I appreciate the second and third opinions, I'll be on here shortly I'm sure with more questions.

__________________
Mistakes of a rookie

Bob Kovacs

So you agreed on shorter splices with the contractor- how about with the engineer, considering he's the guy who asked for the long splices, and probably for a reason that neither you or the contractor realize??? And do you really think it's smart to be talking about your "under the table" "no harm no foul" deal on a public forum on the internet, with your company name and address on the bottom of your posts (I'm sure your boss would be thrilled to see that......)??? Doesn't sound like it's "under the table" anymore. And if you really think it's "no harm, no foul", wait until one of the tornados that we've been getting down here in GA all spring tears that building to pieces, and the investigators find that the rebar splices were short- I'm sure the GC will be playing the "I had no knowledge that my masonry contractor was shortening splices" tune really quick.........

firemike

Bob's right, let the engineer decide if it's alright. As of now you and the contractor will be on the chopping block if something does happen, an investigation is done, and they find out it was not built to engineering specs. You have more guts than me making such a drastic change. And I do mean drastic, as in you are cutting the overlap in half, without even knowing WHY it was set at 52" in the first place.

Several years ago I got a call at 3:30 in the morning from a hotel I used to do work for. The desk clerk told me that part of the ceiling caved in in the pool area (indoor). I got there and sure enough there were large chunks of concrete all over the concrete patio and in the pool. Went up on top of the single story roof, and an HVAC unit was smashed, and there was a hole was in the prestressed concrete roof deck (double "T").

After a little looking, we noticed that one of the concrete block corbels had fallen off the top floor of the 9 story tower, smashed the HVAC unit, and punched through the roof. Long story short, the investigator determined the contractor did not follow the engineering specs and used his own "method" of reinforcement. (The investigator calculated that the piece that fell weighed approximatly 870 pounds.) It took 5+ years for it to fail, but it did, and luckily nobody got hurt, but the contractor spent a small fortune engineering a suitable repair method and 6 weeks rebuilding/reinforcing the 17 other corbels.

And as for it being " "under the table" without really anyone knowing", Bob is also right there. As I post this there are 117 views of this particular thread. Given there are a few that might have viewed it a couple times or more, I am guessing thet there are at least 100 people right now that "do" know about it.

All I am really saying is IS IT WORTH IT to lay what could be your career as well as someone elses, possibly even someone elses life on the line by not doing it right?

__________________
-Mike-

Chris Johnson

No Harm No Foul!!!

This is the same scenario for the Homewood Suites built in Omaha Nebraska over a year ago...the ICF contractor convinced the GC internal vibration wasn't needed...The hotel was demolished and they started over again once all the voids were discovered by the EOR.

Word of advise as stated above don't do it without proper documentation

__________________
Chris

tkle

I'd hire an experienced mason who knew what he was doing. You don't cut corners.

skyhook

Was re-engineering the plans in your job description? All you had to do was make sure the plans were followed to the letter. Now everybody is screwed. You suck Jorge.

__________________

jadleybray

Why on earth wouldn't you just call the engineer? He gets paid big bucks for lots of school and liability. Probably not in this case, but there are often several avenues or methods of construction to meet the engineer's criteria and the builders criteria IE: building costs.

essrmo

alot of trolls on this website. some make us happy when they get here, some make us happy when they leaf.

Justbuilding

I agree
And the GC running that jobsite is a freaking idiot too!!!
When the inspectors see it, don't you think they will question how the two of you came up with a different lap requirement then the engineer spec'd? Great job! Now all credibility for you is gone with the inspectors, how many courses are you going to have to tear down, because you wanted to save a few bucks, How much is it going to cost tear down and start over?

19kevin56

Jorge,

This "agreement" gives your company unlimited liability in the event of a failure at some point in the future. I guarantee you that the GC's superintendent will have a memory lapse at that point. I would advise you to discuss this with your superiors. If one of my superintendents made such an agreement without my knowledge or consent, he would no longer be one of my superintendents.

Regards

Kevin

TWOM JDuran

I immediately regret posting the information on here, absolutely should have taken a completely different approach to this situation. As it stands though, there have been a bunch of mistakes on this job that should never be left up to the subcontracted mason to decide, obviously the GC is who is paying us and therefore we listen to what he has to say.

I do, however, value the opinions of others in the field and have no other course of action but to bow out and continue to learn. These people we are working for are very unprofessional and obviously still learning.

On a lighter note, Fortunately I do ask questions before any huge decisions are made and everyone mutually decided to follow the plans as goes, take our loss and make this a learning experience. An expensive one at that. The project is going smoothly, and I the brutal honesty on this board is refreshing.

I do suck, but hopefully with some support and other opinions i can begin to change that.

Again... I cant even be mad or upset about this... you guys are seasoned veterans in your own respect and I hope we can all help each other do the job right. Thanks again.

__________________
Mistakes of a rookie

neolitic

You may not be making any money,
but you'll sleep better.
And you can walk with the stand-up guys.

__________________
Put your location in your profile!
(Sorry....it seems there really are dumb questions)

Justbuilding

I agree with listen, but call BS when they are wrong. At the end of the day what you have is your ethics and credibility. Lose that and you are done, who wants to work with a liar and a cheat?
As a Supt I ALWAYS want it faster and cheaper but more importantly I want it done right even at cost to the schedule or budget. Right to me is first code, then plans and specs, then cost. If there is conflicts between design and code, then there are questions to the design team and I wait for the answer before moving forward, and the schedule can go hang itself.
When the project is done, I want to look the owner in the eye and say this building is going to give you years of satisfaction.
I don't want to come back in 1 year or 5 years or 2 months and start fixing problems on their building because of stupid shortcuts driven by schedule or whatever.
Good luck

Masonman

First poster here but have been observing for a while now. When reading this Im wondering when you are going to start substituting break time for nap time, what a bunch of cry babys. Just because something is hard or inconvenient doesnt mean that you can deviate from the structural requirements. Typicaly when there are 2 bars in a cell that means that is is part of a masony collum, or a major structural component of the building. When Im loking at a plate that some engineer pulled out of his ass, that has horizontal and vertical dba's I dont think, oh mabe Ill just leave this one out. Masons around here pride them selves on constructing buildings properly, and if they dont there kicking turds. All I can sugest is build it right or it will come back and bite you and if you get lucky and get away with it than you are only contributing to the poor workmanship that is becomming more and more common. Cut some A block and take a nap.

skyhook

[quote=Justbuilding;455001]Right to me is first code, then plans and specs, then cost. If there is conflicts between design and code, then there are questions to the design team and I wait. quote]

The approved plans overide everything. If you don't like the design, say so before the plans go through plan check. Once they are approved, the only obligation is to build it to plan.

__________________