Design, Testing, and Automated Monitoring of ACIP Piles in Residual Soils: Fid-Bau Portal

Design, Testing, and Automated Monitoring of ACIP Piles in Residual Soils

Lacz, Stephen W. / Wells, Richard C.

The new FedEx Mid-Atlantic Hub Sort/Truck Building contains an automated network of scanners and conveyors, moving the packages for mainly air to air transfer. Original site topography included a significant drainage feature and pond transecting the site directly below the proposed structure. Deep structural soil fill depths up to 18.3 m (60 feet) were placed by the grading contractor to level the site prior to property transfer. Due to the variable subsurface profile, including deep alluvial soils and depth to partially weathered rock, groundwater elevation, economics and an accelerated construction schedule, augered cast-in-place (ACIP) piles were selected. The 406.4 mm (16 inch) diameter ACIP piles were designed using an allowable load of 889.6 kN (100 tons) each, bearing in partially weathered rock. A load test program consisting of two compression tests and three tensile tests was performed to confirm the design parameters. As part of the Quality Control Program and due to the subsurface variability, all of the piles installed on site were monitored using an automated monitoring equipment (AME) system to measure the drilling and grouting parameters. The benefit of this system included efficient drilling, operator confidence and not drilling "blind" between borings. Careful consideration of the subsurface profile, structure performance criteria and deep foundation system design, load testing and installation, combined with good design team communication, resulted in the successful execution of this phase of the project.