BANK CENTER EXPANSION
MORRIS-SHEA PROJECT COMPONENTS
16 INCH DIAMETER – 83 PILES
PILE DEPTHS – 44 to 62.5 FEET
Morris-Shea, a leading deep foundation contractor, installed 83 DeWaal piles as a deep foundation for bank center headquarters in Tampa, Florida. The site of the new 138,000-sq.-ft. building is an extension of the existing corporate campus. The Morris-Shea engineering team redesigned the original specifications to better accommodate the site’s restricted access and improve load capacity. Morris-Shea’s compact Fundex TTD-50 drill rig was perfectly suited to operate in the tight confines of the job site – maneuvering through four separate limited access work areas, laying down for multiple moves under permanent walkway structures, and installing piles while operating only inches away from partially demolished buildings.
DEEP FOUNDATION PILE SYSTEM
DeWaal drilled, full displacement, cast-in-place concrete piles were installed by a powerful, fixed mast drill rig capable of applying high rotational torque and crowd forces to the unique tool. This single-pass deep foundation construction process densified the soil, improved shaft friction, and increased overall pile capacity. As the DeWaal tool advanced into the ground, the partial displacement auger transported soil to the full displacement element. Prior to lifting the tool, the drill stem was filled with a self-consolidating, high slump, coarse aggregate concrete. It functioned as a tremie pipe from which pressurized concrete owed while the tooling was withdrawn.
VALUE ENGINEERED REDESIGN
Morris-Shea redesigned the project’s original specifications for augercast piles as deep foundation for bank center construction. Due to low headroom/access requirements, MSB proposed the use of a smaller Fundex TTD-50 drill rig and installation of DeWaal piles on a 1:1 basis. The DeWaal Pile System also improved load capacity and production rates.
SOIL CONDITIONS / TESTINGS
Silty sands and sandy clays are layered throughout the job site. A hard limestone subsurface varied in depth from approximately 44 to 62.5 feet deep. Cone Penetration Tests (CPT) were conducted at numerous job site locations and a successful compression load test was performed.