This method can be used for almost every type of building, and it can produce low cost piles in relation to their capacity.

Grout Driven Pile (GDP) is a method for providing a driven, cast in place, end bearing pile. This method has worldwide applications, and has become commonplace for the commercial building industry in the Pacific Northwest. Traditionally, this is accomplished by attaching an oversized, closed ended bottom shoe to a steel casing (mandrel) and driving it to bearing. The driving shoe is then released and grout is pumped through the mandrel to the bottom as it is extracted. Some installation methods pump grout through side ports in the mandrel during driving as well. After grout has been pumped to the top of the pile and the mandrel has been removed, a rebar cage and/or centralizer bar is installed back down the pile column through the fluid grout. Grout Driven Pile have traditionally been used for axial working loads in the 50-100 ton range, but working loads as high as 200 tons have been recorded.

Advantages of Grout Driven Pile

Grout Driven Pile (GDP) are a very economical method for providing medium bearing pile. Their low material costs in relation to traditional steel or precast piling provide a very low cost pile in relation to their capacity. GDP normally provide superior uplift resistance to traditional steel, precast or even to augercast pile. They will also normally achieve both end bearing and uplift design loads earlier than traditional steel, precast, or augercast pile. The removable steel mandrel works as a casing for installation below the water table. Since the soil is displaced laterally during driving, little to no spoil is generated at the top of the hole. This makes for a cleaner foundation than augercast pile, and is especially beneficial in contaminated soil conditions.

Advantages of US Foundations Grout Driven Pile System

US Foundations GDP system has several working advantages:

USF Grout Driven Pile Projects Diameter Depth Working Load
Springfield Shop Foundation 16" 20-30' 45 tons
PDX Demonstration/Test Pile 16" 55-60' 100 tons