Geopier Foundation Company - Midwest (GFC) and Foundation Service Corporation recently hosted a Geopier technology field demonstration at two building construction sites in Milwaukee, WI.
Geopier technologies were selected by the design teams over driven pile foundations for a two-story senior housing addition in Menomonee Falls, and a four-story apartment complex on a brownfield redevelopment site in Bay View.
GFC is the licensed designer of Geopier technologies (GEOPIER, IMPACT system, RAMPACT system) in the Midwest, and Foundation Service Corporation is a licensed installation contractor.
Steve Weyda, PE, the local GFC geotechnical design engineer, explained the advantages of reinforcing the poor soils for these buildings. The technologies create a stiff subgrade for normal spread footings and floor slabs-on-grade, which are much more practical to construct and less expensive than pile caps, grade beams and structural slabs. The Geopier methods adhere to the principles of sustainability by using locally derived native and recycled aggregates, low fuel consumption construction, and minimal site disturbance to name a few.
The patented GEOPIER process was used for the senior housing addition to reinforce existing fill and peat up to 28 feet deep. A Geopier is constructed by first drilling a hole to the desired depth, and then ramming thin lifts of aggregate into the hole with a specially designed tamper. This creates a very dense column of aggregate and increases the confining pressure (strength) of the soils surrounding each Geopier. The project team related that using the Geopier system led to a savings of more than $100,000.
Another proprietary technology, the IMPACT system, stiffened the poor soils at the apartment complex site. The Impact system is a displacement process ideally suited to handle the foundry sands and other historical uncontrolled fills dumped at this brownfield site, along with shallow groundwater. An Impact pier is constructed with a heavy steel mandrel pipe that is forced into the ground with high crowd force and vertical ramming energy. Aggregate is conveyed through the pipe to the tip, and forced laterally and downward into the soft soils in thin lifts. Weyda indicated that the Impact system supported individual column loads of up to 300,000 pounds.
In true Wisconsin fashion, the field demonstration was wrapped up at a local brew pub in St. Francis. The brew pub is founded over Geopier-reinforced soils.
For more information on Geopier technologies, please visit the website www.geopiermidwest.com.
Geo-Ingenuity. Revolutionizing soil reinforcement.
