How can I color/style match concrete patch to old sidewalk? See image

Question

As you can see, I attempted patching an old spalling concrete sidewalk with premix concrete patching product. I was very disappointed with the results. The color isn't remotely close to the existing sidewalk and it did not trowel out as smooth as I'd hoped. My question is first, how should I remove the failed patch attempt? And how can I get a better match to the existing?

It doesn't have to be perfect. I thought about mixing actual concrete, patching, and then pushing in sand and pea gravel at the top to try to replicate the texture and color. Would that work?

Answer 1

Your repair will never match... perfectly.

Your first question: How to remove the bad repair? It will be difficult and you won’t be able to remove it all. I’d start with a chisel and try a grinder when it is low enough that the marks can be covered during the repair.

I’d consider cutting that entire section out and replacing it with a new pour...especially if the walk is in an important location, like a front walk.

Second question: How to repair? I’ve seen concrete repair by “old-timers” who take great pride in matching color and texture. However, they don’t match it perfectly.

If you want to try, I’d: 1) find a place to experiment so you can pour 8-9 small samples until you get it acceptable, (you’ll need to wait until it dries...28 days between samples,) 2) use concrete coloring and mix it into your mix, 3) find a sufficient amount of rocks that match in size, color, etc.

You will need to hand place the rocks to the same spacing, depth, etc. as the existing.

It’s more “art” than production. It takes a lot of time and patience.

Answer 2

I was able to remove the existing patch using a trowel to scoop out the non dry parts, and a power washer with the highest powered nozzle for the rest. For now, it is back to status quo which is a spalling sidewalk with edges crumbling.

The technique I plan on going with is an "exposed aggregate" technique. I am planning on cutting out the existing section as @Lee Sam suggested. Then, building a form and pouring new concrete, using a hose and brush to rinse of the top coat to get down to the pea gravel aggregate. I'll follow what they do in this video. and probably do some test samples again, as @Lee Sam suggested.