Amoco Building - Amoco, Inc. - Chicago, Illinois
STS provided subsurface exploration and geotechnical engineering including pressuremeter testing, caisson observation and superstructure monitoring for the 80-story building. The caissons were drilled to bedrock and a new seam criteria for each socket penetration was developed, minimizing the amount of rock removal required on future projects. In addition, this was the first Chicago project with a load bearing slurry wall.

One Financial Place - Continental-Turner - Chicago, Illinois
STS participated in a unique foundation design for the 40-story high-rise structure. In-situ pressuremeter testing of the water bearing cohesionless silt layer was conducted. This had been previously avoided as a high load bearing stratum. Combined with the successful use of filtered deep dewatering wells to lower the water table, construction of new caisson foundations immediately adjacent to and below existing belled hardpan caisson-supported structures was permitted.

SOHIO Building - Urban Investment & Development Company - Cleveland, Ohio
STS performed comprehensive geotechnical engineering for the highest structure in Cleveland with the deepest caisson to date in the U.S. at a maximum depth of 252 feet. Services included subsurface exploration, pressuremeter testing and caisson load tests to confirm design assumptions. Specifications and quality assurance procedures were developed for construction of caissons totally underwater without bottom inspection.

AT&T Corporate Center - Stein and Company - Chicago, Illinois
STS performed geotechnical engineering, foundation analysis, and retention system design for a 60-story office tower. Because basement levels went below adjacent footing supported structures, a thickened concrete slurry wall was designed to reduce deflection and settlement during excavation. Movements were measured with inclinometers. Due to the site being occupied by existing hardpan caissons, pressuremeter testing was done to determine depth of new caissons with the highest bearing pressure to date on soil in Chicago at 50 ksf. Filtered dewatering wells were installed to lower water level permitting construction of belled caissons on dense silt below existing caissons.

Two Prudential Plaza - Prudential Realty Group - Chicago, Illinois
STS provided geotechnical engineering including evaluation of subsurface conditions and foundation recommendations for 200 tsf caissons to bedrock, up to 10 feet in diameter. STS also provided field observation services for the caisson and slurry wall construction.

Renaissance Center - Detroit, Michigan
STS was retained by Detroit Renaissance to provide geotechnical engineering and materials testing services for this project, which consisted of four 40-story buildings and one 65-story tower. STS completed the subsurface exploration and provided recommendations for foundation design, bulkhead construction, and a vibration study to evaluate the effects of an existing railroad operation. Field construction, and a vibration study to evaluate the effects of an existing railroad operation. Field construction services included observation and testing of al caisson foundation installation, concrete and soils testing, and structural steel documentation and testing.

311 South Wacker - Lincoln Property Company - Chicago, Illinois
STS was the project geotechnical consultant and the designer of the excavation retention system for the 311 South Wacker building, the tallest concrete building in the world. A combination of crosslot struts, inclined rakers and corner braces were used for the retention system for the lower level garage and the garden areas using the caisson caps as reaction blocks for the inclined rakers. The top down method of construction was used in the tower area. The building floor slabs serve as the interior bracing and thus, additional temporary bracing is eliminated.

Quaker Tower - BCE Developmental Properties - Chicago, Illinois
STS provided a comprehensive construction services testing, monitoring and management program during the substructure and superstructure construction phase for the 38-story high-rise project.