Installing new baseplate over existing exposed agg / pebblecrete surface

[bugbus]

I am designing a new baseplate that will be chemically anchored onto an existing bridge parapet.

The only issue is that the existing parapet has an exposed river gravel (a.k.a. pebblecrete) finish (yes, it was built in the 70s).

What is the best approach here? Break away the pebblecrete locally to get down to the concrete underneath and then built back up with mortar? Or simply apply mortar straight over the pebblecrete?

See below for an idea of the finish:

 

[HTURKAK]

I would prefer applying repair mortar or non-shrink grout over the pebblecrete..










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