Sagging Floor

I have a sagging floor. I am going to support and raise it with a beam and jack posts which will rest on the basement floor. I am concerned if the weight on the jack posts will crack/break the concrete floor. The present jack posts in the basement go through the concrete floor and I assume are sitting on footings beneath. The floor is in good condition now. Will there be a possibility of the weight breaking the floor? Should the posts be on some kind of support pads?