There are two base types of pier & beam foundations. Those with a concrete grade beam around the perimeter and those without.
With a concrete pier & beam:
If a home has a concrete grade beam, the perimeter can be lifted using concrete pressed pilings.
Adjusting interior floor levels: The floors of a pier & beam house sit on beams (typically 4 in X 6 in). The beams are supported by “piers”. These “piers” are typically, poured concrete piers, pre-made concrete blocks, or cedar stumps.
The floor levels can be adjusted by raising the beam off its support and adding or removing steel shims. Sometimes supports (piers) need to be added or changed out if they have failed.
The best way to prevent failure is keep your foundation dry from any type of moisture. If you continue to get moister under your foundation, even the best piers will eventually fail.
On a pier & beam foundation, it is often necessary to replace wood located under the floor. The wood may be rotted or damaged due to moisture and/or insects.