Click on a photo to enlarge.
The Before Picture is a void, that Saber exposed, under the foundation with a sliding glass door.
The After picture shows how Push Piers are installed under sliders. A angle is used with two foundation piers to lift this section uniformly, and avoid damage to the slider.
The Before Picture shows a Sinking Foundation, that is Cracking.
The After Picture shows installed Push Piers, that Lift the Foundation, where it has sunk.
Raised foundation support
Seismic retrofit under a raised foundation in Glendora