Concrete Removal and Repair 1

[EngrRC]

So, I have a manhole opening on a 350mm slab. The manhole cover would supposedly bear on a 50mmx50mm recess on the 350mm slab. Now, the manhole cover apparently needs to sit on a 90mmx90mm recess so part of the slab surface needs to be hacked.
My question is, how do I repair the concrete slab so that it would still have adequate concrete cover and what about the reinforcement that would need to be cut (possibly affecting the supporting pit wall reinforcements)?

 

[bridgebuster]

The coffee hasn't quite kicked in yet but I see two options:

1. cut off the wall below the bracket and start over

2. Can you raise the grade slightly to avoid cutting the top part of the hairpin bar? This way you only need to cut out a small piece and concrete and you don't need to drill and grout horizontal bars. No matter, where you have bars at the surface, you'll need to chip out the concrete around the bars; go at least an inch deep; cut off the bars; and patch with epoxy mortar. Saw cutting vertically shouldn't be a problem but you probably won't be able to completely saw cut horizontally, so you'll have to chip out concrete. Sika has a product - the name escapes me at the moment - that can be applied 1/8" thick to smooth out surfaces. I saw it used on a wastewater treatment plant and it worked well.