Footing
A footing is dug out under the floor.
Footing with gravel
A jack is placed on top of the concrete footing and gravel is placed around the jack before concrete is replaced.
Supplemental beam
Because the the floor is weak where the stair case is, an extra beam is installed here.
Smartjack under main beam.
The main beam of the home needs support after years of being installed. It will likely get soft from moisture over the years.