Micropiles are deep foundation friction piles constructed using high strength steel casings. A friction pile allows transfer of structural load pressure put on them to the soil around them.The friction creates an adhesive effect where the pile and the soil connect. Micropile underpinning is the process of creating small diameter drilled and grouted friction piles.
Micro-piles are piles modelled on the spot to serve as deep foundations and highly tensioned stress along the shaft, composed of sand and cement mortar and thoroughly reinforced throughout its length. Micro-piles are employed in highly compact or consistent ground or in the ground where bedrock or rocky formations are found, in which excavating may only take place with the use of rotating hydraulic drills. They may be placed in an inclined position.
Common uses
- Provide structural support to most structures
- Underpin foundations
- Enhance mass stability
- Transfer loads
Advantages
- Resists compressive, uplift/tension, and lateral loads
- Comprehensive fleet of rigs and tooling for difficult subsurface conditions and limited access
- May avoid utility re-routing
- Fast and cost effective
- Alleviates quality assurance concerns associated with cast-in-place piling in weak soils
- Can be combined with other techniques to meet unique or complex project requirements cost-effectively and efficiently