That is some major damage.
I too have caused damage to new concrete (2 years old) with a 3 arm surface cleaner and 1503 nozzles,.. pump head at 3000psi though 200ft of 1/2 hose.
However with the same setup above at other properties this works great even in repaired sections of concrete.
Its best to test an area for any new account or new section of concrete of an existing account.
Its nice to have the height adjustable surface cleaners for this reason, no need to change nozzles
I wish someone could identify the fluid dynamics of high pressure nozzles,... impact force at different angles and height, temp reduction from expansion etc, that would be a great tool.