Nestled on Naples Bay is the Cove Inn a unique waterfront hotel. The Chic accommodations provide magazine cover views and an authentic old Florida sense of place. The Cove Inn is one of the few waterfront hotels in Naples with direct access to the Gulf of Mexico. It is right around the corner from Crayton Cove with its vintage shops and the Naples City Docks.
A traveler casually walking to catch dinner, or a glimpse of frolicking dolphins will rarely have time to notice the complicated infrastructure of protective seawalls. But, if they did take a good look around, these individuals may notice that the complexity of seawalls. These structures are in a perpetual state of upgrade or repair after being in existence for 30 years.
Recently, our company was awarded a construction contract from Turrel Hall and Associates to install supplemental helical tie-back anchors for a failing seawall.
From a general contractor’s perspective, installing piles for this job might not seem particularly challenging, but the pile installation must take place by water. FMC was hired to simply install helical anchors for a marina improvement project. Specifically, to reinforce the aging seawall and add significant longevity and assurance to the structure.
As it turned out, this job was extremely challenging from a logistical, and a customer service point of view. Why? Precisely because of where the job was located with busy onlookers on vacation and boat owners requiring access to their yachts.
Florida Marine Construction elected to utilize 1 ½” square shaft helical tieback anchors for the Cove Inn Marina project. The requirement for an engineered and reliable method that could attain the load requirements of the seawall project left helical piles as the only remaining option. The ability of FMC to mobilize floating equipment and prepare for the quick helical anchor installation allowed the project to move forward without additional costly delays.
The helical pile depths ranged from 21’ to 28’ in depth. Upon completion of the helical pile installation, couplings and terminations were provided for final termination unto the seawall panel. The project was completed over a period of 4 days.
- Twenty-five (25) “Chance” (1-1/2-inch square bar) helical tieback anchors with a 10”-12”- double-helix lead section was installed beneath utilities, sidewalks and retaining walls. The Caterpillar 301 CR excavator with a specialized mast system powered by a 10k Pro-Dig drive head was utilized to install the anchors. The helical tieback anchors were hydraulically rotated to 2,000 P.S.I., providing a tension load of 12 kips.
- Twenty-five (25) “Chance” inch square bar) helical tieback anchors with a 10”-12”- double-helix lead sections.
- Sixty-eight (68) additional 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 within the new seawall cap to provide lateral structural support. All tiebacks and anchors were load tested with a 30-ton center pull ram to secure required engineered load capacity of 12 KIPS.