Underpinning
Underpinning is the process of strengthening and stabilizing the
foundation of a building or other structure.
Underpinning is accomplished by digging underneath shallow
footings and extending the reach of the foundation by pouring in
concrete. The purpose is to extend the reach of the foundation in
depth or in breadth so it either rests on a stronger soil or
distributes its load across a greater area.
Micropiles and jet grouting are commonly used in
underpinning.
Underpinning is required when:
- The construction of nearby structures affects the soil
supporting existing foundations.
- The usage of the structure has changed
- The soil supporting the foundation may have changed
- The original foundation is not strong or stable enough
