Naples Land Yacht Harbor, located in North Naples, Florida in May 2018 awarded Coastal Foundation Solutions a contract for the installation of one hundred ninety-eight (198) supplementary helical tieback anchors. Coastal Foundation Solutions along with Turrell Hall and Associates designed a system to prevent any further movement to the existing concrete seawall and provide stabilization to the structure. A Seawall Saver Helical Tie-Back anchor system was chosen by the owner, contractor, and engineer as the desired method to stabilize the seawall structure. The system was installed by Coastal Foundation Solutions (CFS), a Certified Installer of Seawall Saver Helical Foundations Systems headquartered in Matlacha, Florida.
Due to the proximity of the homes to the seawall (10 feet), access was severely constrained. The project entailed utilization of a specialized barge to provide water accessibility to the seawall structure for designated repairs.
One Hundred Ninety-Eight (198) Seawall Saver SS125 (1-1/4-inch square bar) helical tieback anchors with a 6”x6”x6” triple-helix lead section was installed through a six-inch diameter cavity opening. Coastal Foundation Solutions utilized combinations of specialized concrete core bits to gain access through existing 8” thick vertical seawall. The 2019 Kubota KX040 excavator with a specialized mast system powered by a 6K Pro-Dig drive head was utilized to install the anchors. Seawall Saver helical extensions imbedded the tieback anchors to lengths of 15 to 21 feet to attain final installation torques. The cavity was filled with a 6” polystyrene foam plug and a H.D.E.P. membrane to prevent soil loss.
The helical tieback anchors were hydraulically rotated to 2,000 P.S.I., providing a tension load of 12 kips.
Two Hundred Sixty-Four (264) additional SS125 extensions were used to attain dynamic load capacity due to sub-surface soil disparities.
The helical tie back anchor was linked to a hot dipped galvanized steel channel, placed at the outside wall face to provide lateral structural support. All tiebacks and anchors were load testing with a 30-ton center pull ram to secure required engineered load capacity.