Micropiles are small diameter, bored cast-in-place piles, with most of the applied load being resisted by steel reinforcement. They are constructed by drilling a borehole, often using casing, then placing steel reinforcement and grouting the hole. Micropiles have a wide range of uses and are becoming a more mainstream method of supporting and resupporting foundations, seismic retrofits, stabilization of slopes and even earth retention.
Micropiles are usually designed in small clusters or groups with each typically carrying an equal amount of load. These piles may also be designed with a batter to improve the lateral rigidity of the group. They can be designed to resist a combination of compression, tension and lateral forces.
Micropiles are an ideal pile for complex sites where low vibration or low noise levels are required, or where limited access such as low headroom and drilling is difficult. Other site conditions that make micropiles attractive are: obstructions, large cobbles or boulders, nearby sensitive structures, karst topography or high groundwater conditions. The unique characteristics of micropiles make them a perfect solution when other deep foundation methods are not suitable.
- Creates a pile with a relatively high axial load capacity
- Works in compression and tension
- Lightweight rotary percussive equipment can be used
- Easily installed within confined spaces
- No harmful vibrations or noise to surrounding structures
- Minimal spoil generation on contaminated sites
- Structural Support of Directly Loaded Piles
- New Foundatiions
- Underpinning of Existing Structures
- Seismic Retrofitting
- Reinforcement for Slope Stabilization and Settlement Reduction
- Support of Excavation - Soldier Piles
- Permanent Retaining Walls