Pulldown Micropiles
Helical Pulldown Micropiles
The Helical Pulldown Micropile (HPM) is a system for constructing a grout column around the shaft of a standard Helical Pile Foundation System to increase capacity when the normal helicals won’t achieve the job requirements.
The Helical Pulldown Micropile does not require removing spoils from the site. By combining both end-bearing on the helical plates and skin friction along the rough surface of the grout column, the result is a higher capacity pile system.
Developed in 1997 for sites with especially weak surface soils, this patented innovative application of the helical pile integrates Portland cement–based grout to increase the section properties of the shaft.
The Helical Pulldown Micropile brings the advantages of the pre-engineered helical pile to higher load applications. The Helical Pulldown Micropile can provide an additional 50% to 100% capacity when compared to an ungrouted helical pier in the same soil conditions.
By “pulling down” a flowable, expansive grout as the foundation is screwed into the soil, these micropiles create a deep foundation with both a friction-bearing central shaft and end-bearing helical plates in competent substrata.
CHANCE Helical Foundations install quickly in any weather condition. A hydraulically powered torque motor mounts to standard construction equipment such as a digger-derrick truck, line truck, rubber tired backhoe, track-hoe excavator, or front-end skid-steer loader. Continuous torque and crowd are applied to advance the Helical Pulldown Micropile into the soil.
Benefits & Applications
This CHANCE product comes with the advantages of increased capacity and corrosion resistance for long-term performance. The installation process itself actually enables grout to be pulled down around the helix as it is screwed into the soil. This speeds up the overall project and allows for greater strength.
Why Use CHANCE's Helical Pulldown Micropiles
Benefits of the Pulldown Micropile
- Speed: 40–50 piles per day/per crew
- High capacity
- Predictable results
- Cost-effective
- Labor-saving: smaller crews
- No pre-drilling
- Resistance to buckling in weak soils
- Stiffer pile (deflects less at a particular load)
- Additional corrosion resistance in aggressive soils
Deep Foundation Applications
- Commercial/industrial
- High capacity/greater than 100 tons
- Underpinning applications
- New construction
- Build on weak soil sites
- Limited access
- Bridges
Helical Pulldown Micropile Installation
CHANCE Helical Pulldown Micropiles are used to form a grout column around the shaft of a standard helical anchor/pile. The installation process can employ grout only or grout in combination with either steel or PVC casing. To start, a helical anchor/pile drives into the soil by applying torque to the shaft. The helical bearing plates require significant force or torque to advance the helical pile into the soil.
After the lead section containing helical plates penetrates the soil, a lead displacement plate and extension are placed onto the shaft. Torque is again applied on the assembly to advance the helical plates, which pulls the displacement plate downward, forcing soil outward and creating a cylindrical void around the shaft.
From a reservoir at the surface, a flowable grout immediately fills this void surrounding the shaft. Additional extensions and displacement plates are added until the helical bearing plates reach the minimum depth required or competent load-bearing soil. This displacement pile system does not require removing spoils from the site.
Intech Anchoring Supports Your Deep Foundation Commercial Solutions
You can always count on us to deliver high-quality deep foundation products and solutions, but our professional assistance does not stop there. The most significant factor that separates us from the competition is our team and their experience. We are able to provide industry-leading support thanks to our staff of engineers and experts. They work every day to deliver the products your projects need. We are not just here to sell and rent our products; Intech Anchoring is here to help you succeed.
We are equipped for on-time delivery from one of our two locations, both with ample inventories. Our team provides product and installation training geared for your unique projects. You can take advantage of our expertise with on-site assistance. Our team members will be there to ensure that everything is coordinated correctly and according to engineering specifications. We can even assist in field certifications for your employees. Intech Anchoring is prepared to be your partner in success with all of these services and a library of the best products available on the market today.
To learn more about deep foundation pulldown micropiles, contact Intech Anchoring today.
