Usually I'm providing answers, but today I have a question. My church has a set of concrete steps for which the nosings have broken back about 4". The concrete is deteriorated badly, but only on the bottom 3 steps. The church has received bids for the steps from 30K-50K. They have asked me to do a repair of the steps (again). 2 years ago, I repaired the nosings with a patching compound, but due to the deteriorated nature of the steps, I warned the church the patch wouldn't hold much more than a year (we got 2).
I am planning on removing the bottom 3 steps by taking a RAGrinder and scoring the steps up to the side railings (brick), and at the inside bend of the 3rd step, removing, forming, and repouring new concrete.
Given the step has a footer under that portion, I plan on taking rebar, and tying 2-3 pieces of rebar from each side to each side (about 6 feet), and then putting rebar in to tie the top portion of the step to the new pour.
Once we have the rebar in place, I'd like to form and pour with a good concrete mix purchased from a local concrete supplier.
I'm soliciting opinions from the board on these issues and any other comments.
1. Should rebar be used, if not, what will keep the 2 steps from moving differently? Coated rebar to keep from getting rustthrough?
2. If the step doesn't have a standard footing, but is on rubble (as some old steps were), should we dig through the rubble and put a couple 12" tubes down? Minnesota location. (I'm kind of worried about digging through big rock, etc.)
3. Is there any concern about these two steps (old and new) moving differently, applying a control joint, or is this just an opportunity for water infiltration a/o shifting from freezing and thawing.
I'm hoping to get no less than 5 years, and hopefully 10 from this repair.
Thanks to anyone and all that reply. It is kind of a wierd way to do a repair, but this is what the church has tasked me with and I must get it done before April 27.