High Lift Grouting

[AJ817]

Hello,

We have a contractor who wants to do high lift grouting with bars spliced with the max 12'8" grout pour. They ordered rebar for 4' lifts and now want to change to high lift.

I can't seem to find anything in TMS that specifically says they can't do this. But diagrams in TMS as well as in the NMCA show no splice within the 12'-8" pour. In the diagram in the tek manual, the text reads "Bars installed full length (no splicing). So it seems clear to me that no splicing within the pour is acceptable.

The pushback I am getting is that under "wall construction" in the tek manual it says "laps are made at the end of grout pours and any time the bar has to be spliced."

Anyone have any thoughts?

Thank you!

 

[GC_Hopi]

My understanding is splices are fine and the cleanouts should be aligned with the splices so during placement of lifts there is visual verification that rebar splices do not become loose. Also there needs to be enough room in the cell for grouting per TMS. If the contractor is a pain have them add a full length bar in the same cell as the spliced bars if there is enough room.

 

[masonrygeek]

As long as the lap lengths are the right dimension and, as GC stated above. you have the appropriate room for grout then I see no reason you couldn't do it this way. This is one of the reasons that masonry grout has a slump of 8-11" - so that it can flow around areas that are restricted. Most masons use a single bar since it might be hard to maintain the splice since the higher bar will want to drop. A good tie would be required to hold it in place before and while the grout installation occurs. Some increased inspection msy be warranted here.

 

[AJ817]

Thank you for your responses! Incase you are still following, I talked to NCMA and they say bar splices should only be placed at the top of a grout pour. So if you are pouring 11' there would need to be a full length bar of 11' plus additional lap length for the reinforcement in the next lift, if you have another lift.