Geotechnology engineers working at Centene project site


Location: Clayton, Missouri

Client: CMC Hanley, LLC

Services: Construction Observation, Drilling, Geotechnical, Materials Testing, Special Inspections


The Phase II Centene tower project includes redevelopment of a site at the southeast corner of Forsyth Boulevard and South Hanley Road in Clayton, Missouri. The proposed development includes two below grade levels, and up to 28 above grade levels for a hotel, office and garage.  Geotechnology performed a subsurface exploration for this project. We also provided a report with recommendations for deep foundations and shoring stability.

The Phase II Centene Project Background

The structure is planned to be supported on 36 straight shaft drilled piers and 22 belled piers bearing on the underlying limestone and Lagonda shale bedrock, respectively. The straight shaft diameters vary from 42- to 108-inches. The belled pier shaft and bell diameters range from 30- to 48, and 42- to 90-inches, respectively. Column loads are in the range of 600 to 14,000 kips. Uplift loads, where present range from 100 to 3,700 kips.

Geotechnology performed drilled pier probing to determine the bearing level required to achieve the necessary capacity at the drilled pier foundation locations. Probing helps to predetermine the drilled pier bottom depth, which reduces unknowns and increases construction efficiency. Additionally, and more importantly, probing eliminates the need for dangerous manned entry.

Geotechnology is currently providing special inspections, construction observation and materials testing for the project. Our inspection and testing services cover utility relocations, tie-back shoring systems, drilled piers, concrete columns and flatwork and reinforcing steel. These services also cover welded and bolted structural steel framing, masonry, fireproofing, floor flatness and levelness, and roof anchors.

The field exploration consisted of drilling 55 probe holes, one at each of the drilled pier foundation locations.