Your best option is to use a large circular saw that sports a diamond blade you can simply rent one.
Cutting concrete with circular saw.
Remove the old blade.
Put on your safety gear.
If you have a blade in the circular saw you need to remove it so you can attach the diamond.
Your safety is vital when using any tool.
How to cut concrete with a circular saw step 1.
I d like to cut 4 inches thick concrete.
Will i have to cut the whole 4 inches of it.
Making sure you are using the right blade for the job is crucial.
Maybe you ll also have to use a jackhammer or a sledgehammer if your circular saw doesn t cut through the entire thickness of the sidewalk.
The reason a diamond blade is advised for cutting.