Concrete Pedestal: Too Short

[RPMG]

Problem: Bottom of base plate elevation is 7" above the Top of the concrete pedestal/pier.

- I looked into grouting 7", and it is not recommended. Concrete will be used to raise the piers.

- Anchorage and embedment are not a problem.

- The contractor proposed to install anchors, hard shim the base plate, level column with leveling nuts, and remove the shim just prior to pouring. I don't have any concerns with this.

Questions:

1. There isn't room to dowel, and I would like to place ties around the anchors themselves. Are there any problems associated with this? I've proposed this before with short piers, and it wasn't well received.

2. The two alternatives are (a) 7" of concrete, or (b) 5" of concrete and 2" grout. I know that concrete shrinks, but in this case, I would be fine with the anchors permanently carrying the compressive load if braced by the concrete. What do you think, grout it anyway?

 

[BAretired]

Unless you grout it, there will be a shrinkage gap under the plate. If the anchor bolts are adequate to carry the load by themselves, you don't need to grout it, but for the small cost involved, I believe it is better to grout it.

BA

 

[SAIL3]

yes, I would use grout and also ties around the anchor bolts....

 

[yaschief]

Non Shrink Grout with 1/4" Pea Stone as aggregate placed in one lift would be acceptable.