A Cost-Effective Micropile Alternative
Working close to existing structures? Constrained sites? Interior applications? Concerned about vibrations from foundation construction?
These are all common reasons why project teams specify drilled micropiles for foundation support on projects. Project teams also deal with the reality that drilled micropiles are often expensive and slow to install.
A Drilled Micropile Alternative
The Ductile Iron Pile system is a unique hybrid offering advantages of both a driven pile and a drilled micropile. The system is installed using an excavator-mounted medium-sized percussion hammer to rapidly advance the pile using high-frequency percussive (ramming) energy. The high frequency drive energy produces minimal vibrations, allowing the system to effectively work immediately adjacent to existing buildings. Monitoring of projects shows vibration levels (PPV) at a distance of only 2 feet from installation are often below 1 in/second. The Ductile Iron Pile system often provides similar capacities to micropiles in compression and tension by developing a friction bond zone like a micropile. The modular nature of the piles and medium-sized installation equipment allows the system to gain access to tight sites and low overhead (≈20′) situations. In addition, the Plug and Drive connection system results in rapid installations with production rates of 400 to more than 1,000 linear feet per crew day.
While some projects located in basements (˂10’overhead) or dealing with heavy debris or existing foundation drilling are appropriately geared to drilled micropiles, the Ductile Iron Pile system represents a cost-effective and rapid alternative to many other drilled micropile projects. Experience has shown the Ductile Iron Pile alternative to drilled micropiles often cuts the foundation cost and installation time in half or more.
Advantages
- Rapid installation rates (400 to >1,000 ft/day)
- 25 to >50% cost savings over drilled micropiles
- No flushing – limited to no site mess
- Versatile system by developing bond zone for high frictional capacity or end-bearing on dense conditions
For more information on projects where Ductile Iron Piles provided a micropile alternative, check out these projects:
- UPS Distribution Facility – Bridgewater, NJ
- UPS Distribution Facility – Hartford, CT
- 291 Mystic Avenue – Medford, MA
