Concrete can be a problem if you need a hole in it or need to remove a section. You could remove the concrete, but that might not be the solution. Hiring a concrete cutting company may be better for your needs.
Trenches in Concrete
On soil, if you need a trench, you dig one, but if the ground is covered in concrete and you need a trench to run wires or plumbing through, digging a trench is not an option. Flat sawing the concrete is the best solution for these situations, and a concrete cutting company can make the cuts precisely where you need them so you can lay the wiring, conduit, or plumbing in place.
Flat sawing can also help if you are removing a section of concrete but want to leave another part of the concrete undamaged. Multiple cuts in the concrete will allow you to break up the section you want to remove without damaging the part you want to leave in place.
For walls that need a hole in them, wall sawing uses a saw similar to that of the flat saw but with a mount that allows it to cut horizontally. If you need a hole through a concrete wall, this is the best solution. The concrete is cut, and then you can remove just the part you need to have access through. Often, wall sawing allows a window, heating ducts, or plumbing and electrical to run through the concrete wall.
Core drilling through concrete allows a circular hole through the concrete. For plumbing or conduit, the circular hole may work better than cutting a huge square hole out of the wall. If the diameter of the hole is right, a pipe or section of conduit can pass through and leave only a small gap around the pipe. Sealing the hole that the pipe runs through is much easier, and in the long run, is more visually pleasing. In a case where people may see the pipes or conduit, it may be important to keep the holes as clean and neat as possible.
Chain Saw Cutting
For situations where the location of the cut is very tight, cutting the concrete by hand is sometimes a better solution. Some concrete cutting companies use chainsaws with a very specific chain designed for cutting through the concrete. The saw is small and easy for one man to handle alone and allow for cuts that are not possible with a circular blade.