From Engineering to Construction: 117-ton Tank Foundation

Modern infrastructural design and architecture are evolving due to rapid improvements in modern technology and material science. This has raised the bar, calling for construction and engineering companies to rise to the occasion with improvements in foundation systems.

The RumFish Grill was to be added by the Guy Harvey Outpost as a new attraction at St. Pete Beach, Florida. Building this new attraction would require converting a pre-existing commercial site into a new restaurant.

One of the major problems faced by the engineers was transitioning a 40'x15' atrium into a giant aquarium. The atrium site was enclosed by 4 tall walls with water lines buried below creating access problems. Because of this, building a 40'x12'x12' tank required constructing a foundation that could withstand the weight of 33,500 gallons of water and remain stable enough to avoid any leakage. It also was imperative that the foundation could be designed around the existing water lines and installed without disturbing them.

A load of this size – that’s 234,000 pounds, or 117 tons – required a deep foundation system. The foundation system would also have to be installed within a limited access, restricted area and be able to withstand future shifting.

After soil testing and site evaluation, engineers chose helical piles as the best solution to address the challenges posed by the low overhead, restricted access site, and massive weight.

Installation process

When compared to other available options for building deep foundations, helical piles offer a natural edge:

1. They quickly resolve the problem of access and weight.
2. They reduce the risk of vibration that may damage the surrounding infrastructure.
3. Their fast installation process helps save time – and time is money.

Since this project required fast installation along with noise and vibration reduction (because of the closely surrounding infrastructure and buildings), helical piles were the ideal choice.

Installation process

Follow us as we take you through the exciting journey of building the attraction site known as the RumFish Aquarium, made possible by:

• Foundation Technologies, Inc. - CHANCE helical pile distributor
• Acrylic Tank Manufacturing (ATM) – manufacturer of aquarium
• RKM Building Construction, Inc. (RKM) – the primary contractor
• Central Florida Testing Laboratories, Inc. (CFTL) – soil testing and analytics
• Speeler Foundations, Inc. – helical pile installation

1. RKM was contracted to construct the restaurant and aquarium. RKM, in turn, hired CFTL to carry out soil testing and analysis. But CFTL was faced with the challenge of accessing the site. Notably, they had difficulty transporting the drilling rig to the site and had to lift the machine using a crane.
   
   
2. Soil tests were conducted, and their results showed that the soil had a dense sand layer with high load-bearing capacity ranging about 15 to 20 feet deep. The engineers then had to bypass the upper soil layer – specifically, 5 to 6 feet to support the tank. Also, they found an additional soil layer that was suitable for helical piles meaning no extra load on pre-existing utilities or the footings of the surrounding infrastructure.
   
   
3. RKM hired Speeler Foundations to install helical piles – 27 round shafts, to be exact. A drill extension was attached to a mini-excavator to install the helical piles until they attained the required torque capacity or bedrock. Each helical pile could support 15 tons of weight. To adapt to the limited access conditions, the drilling rig had to be lifted over the kitchen with a crane!
   
   
4. Helical piles were installed, and the shafts were welded to a 7'x7'0.5' bearing metal plate to provide load-bearing support. The bearing plate was then fused into a 1-foot-thick slab underneath the tank manufactured by ATM.

Installation was swift and the 27 piles were installed within 48 hours using a mini-excavator.

The RumFish Aquarium was featured on "Reveal: The 10,000 Pound Guy Harvey Tank" as one of the biggest tanks constructed for the show. All the while, the helical piles have been working behind… or rather under… the scenes to make it possible.