Pocketed Handrail Base
Pocketed Handrail Base
(OP)
thread507-287615: Handrail/Guardrail Embedment
I recently had this submitted as part of shop drawing review. Has anyone come across the basis for these formulations? Any references/papers?
I recently had this submitted as part of shop drawing review. Has anyone come across the basis for these formulations? Any references/papers?






RE: Pocketed Handrail Base
RE: Pocketed Handrail Base
Do not like grout-anchored railing posts. In my area of the US they have a tendency to do one of 2 thing:
1. The grout expands and cracks the concrete substructures (all grout goes through a volume change as it cures - it's just a matter of how much), or
2. Over a few seasons the grout and post get pushed upward by the freeze-thaw cycles. I have seen as mush as 6" of upward movement.
My preference is an appropriate embed with a mechanical connection to the post or a UV resistant epoxy in a much smaller pocket (oversize pockets provide too much room for sloppy workmanship).
Ralph
Structures Consulting
Northeast USA
RE: Pocketed Handrail Base
This is the first time I have seen a comprehensive set of calculations. However, I was not sure how some of the formulations were derived. I am hoping they have their basis in some testing or research.
RE: Pocketed Handrail Base
RE: Pocketed Handrail Base
Then you can grout the pipe into the sleeve
RE: Pocketed Handrail Base
RE: Pocketed Handrail Base
Somehow, he is making a square cut (or assuming a pre-cast opening exists) in the 8 inch deep concrete 3.5 x 3.5 inches only 4 inches deep. (Should drill a deeper hole - it's easier and faster than a square opening.)
That means the edge of the hole is 2.25 inches from the side of the concrete. If he is assuming the grout is 10,000 psi strength, then the 3.5x3.5 x 4 inch deep "plug" of grout will be strong enough to hold the 42 high post -> but both the plug and the post will break out the then-walled concrete trying to hold the grouted assembly in place.
He needs to resist 200 lbs force at the top of the 42 inch guardrail, but only has 2 inches of concrete available to do that. (How will he verify 4000 psi concrete?)
RE: Pocketed Handrail Base
RE: Pocketed Handrail Base
I would think a different force diagram would be expected with zero stress at the slab surface, more like a sheet piling or telephone pole analysis.