Though the project was originally designed for auger cast piles, USW provided a more economic and time-saving solution by installing CMC rigid inclusions. Unlike auger cast piles, the CMCs eliminated the need for handling and removing large amounts of spoils. USW also employed a cap grouting approach, with over-grouting to mitigate the risk of voided soils.
USW’s team of experts successfully installed approximately 1,000 CMC rigid inclusions to depths of 50 to 85 ft. Noise, vibrations and general impact were kept to a minimum while working adjacent to a fully operational hospital. One potential issue, a sinkhole at grade that was 6 ft wide and 8 to 10 ft in depth, was avoided after being discovered during site operations. CMCs were eventually installed through the backfilled sinkhole.
In summary, to support the construction of a surgical and patient tower at Florida Hospital Tampa, along with an upgrade and expansion to a central energy plant, USW installed more than 1,000 CMC rigid inclusions to improve poor soils. CMC rigid inclusions reduced spoils as compared to the original auger cast pile design and proved to be an excellent solution to supporting the new structures at a very difficult site with karstic soils.