Tool for grinding a 45 in a concrete slap?

2 days ago I poured a 12' x 13' concrete slab. When I take the form off in a month, I'd like to put a 45 along the top of all the edges because I don't want kids hitting their heads on the sharp corners (the slab isn't flush with the ground-it's up off the ground about 2'). Anyhoo, is there such a grinding wheel or special tool for doing this? I want to take about 3/4" off the corners. The concrete is 5000 PSI with reinforcing fiber. Any concrete people please advise. Thanx.