Geopier® Rammed Aggregate Pier® Systems
Geopier Impact RAPs are ground improvement elements that reinforce unsuitable soils to provide an improved subgrade for traditional shallow footing and slab-on-grade support. Impact RAPs consist of stiff columns of rammed aggregate that are constructed with a patented displacement mandrel equipped with a beveled tamping foot. The mandrel and tamping foot apply direct vertical ramming energy to densely compact successive lifts of high quality crushed rock. The vertical ramming action also increases the lateral stress and improves the surrounding soils, resulting in high-stiffness engineered elements. The displacement mandrel generates little to no excess spoils and eliminates the need for casing or dewatering. This displacement construction method is particularly advantageous on sites with caving soils, contaminated soils, and/or shallow groundwater. Impact RAPs can also be grouted to provide enhanced stiffness through relatively soft soil layers (such as organics or soft clay). For these reasons, Impact RAPs are the most-used widely used Geopier ground improvement system in the Northeastern United States.
