Winghaven a 1100-acre mixed use development began in the mid 1990’s. The development is located in the City of O’Fallon in western St. Charles County, Missouri.
In fall 1998, Reitz & Jens was retained by McEagle Corporation, subsidiary of Paric Corporation, to provide all geotechnical services during design and construction of the first two commercial buildings at Winghaven. These projects included a 3-story, 180,000 sf structure and a 2-story, 65,000 sf structure. Both structures were near the edge of deep ravines. The final development plans called for extensive cuts in parking areas and fills up to 20 feet deep to create the building pads. The geotechnical report recommended the buildings to be founded on shallow spread footings, and also made recommendations on how to treat the high plasticity clays that exist near the building and parking lot subgrades.
In 1999 our firm was retained by MasterCard International to provide all geotechnical services during design of their headquarters campus at Winghaven. Three of the structures were typical office buildings, the fourth structure was a datacenter that controlled all of MasterCard’s North American operations.
Several of the borings beneath the datacenter discovered voids in the high plastic residual clays above the underlying bedrock. Because of the datacenter’s critical operations, MasterCard determined that it must be designed to withstand any predictable seismic event. As a result of the subsurface drilling, Reitz & Jens completed a geophysical investigation beneath the datacenter to determine if any additional voids were present. The geophysical survey was completed in the fall of 1999 using seismic refraction and gravity methods. The survey found no additional voids of the size discovered during test drilling.
As a result of the test drilling and geophysical investigations, the geotechnical report recommended that all four buildings should be founded on shallow spread footings. The voids that were discovered during the investigation were treated with a combination of excavation and filling with crushed stone and high pressure grout. Reitz & Jens was periodically called out to the site during construction to review issues that developed during construction, including those created by the other quality control firm. Construction for MasterCard was completed by the spring of 2001.
McEagle again retained Reitz & Jens in 2001 to provide geotechnical design and construction phase services on three new office buildings. Geotechnical investigations via test borings were performed on all three buildings. Because of the buildings’ non-critical nature and their locations away from suspected karst areas, geophysical surveys were not performed in the area of these structures. The geotechnical reports recommended similar design and construction requirements for the new building foundations and site improvements as in previous reports for this development. One of these buildings was built in early 2002 with Reitz & Jens providing field quality control services during construction. Paric is waiting for economic conditions to improve before constructing the two other buildings.