Established in 2012, Rabbit Hole Distillery is situated in Campbellsburg, Kentucky, and annually produces around 27,000 barrels of premium spirits. Frost Engineering was commissioned to provide structural engineering services, crafting an innovative, high-density storage solution to accommodate roughly 25,000 whiskey barrels in a compact area of 10,800 square feet.

The Frost team collaborated with structural engineering researchers from the University of Notre Dame to address the challenges of building rickhouses more rapidly and cost-effectively, while also mitigating the risks associated with increasing insurance expenses and dangers such as fires and windstorms.

The Frost-Notre Dame team, working together and in collaboration with metal racking industry partners, accelerated the optimization of the design, fabrication and installation of light-gauge steel storage rack products for use in constructing rack-supported barreled spirits rickhouses by experimentally validating the performance of semi-rigid “moment frame” connections to quantify the range of rotational stiffnesses, strengths and reliabilities of these components.

Semi-rigid “moment frame” connections have historically been used in various other materials, such as hot-rolled steel and reinforced concrete, to solve one of the most fundamental challenges of structural framing, which is to provide lateral stability and stiffness while avoiding clashes with access paths, utilities, as well as architectural features.

Frost designed a schematic structural solution, designed and executed an experimental validation testing program, and completed a final structural design of the foundations and framing for two barreled spirit rickhouses, each with an approximate construction cost of $5 million.

Reverse cyclic testing and subsequent statistical reliability analysis was performed in accordance with the standards that govern light-gauge steel rack design and testing, including RMI/ANSI MH16.1 Section 9.6, AISI S100 Commentary Chapter K, and FEMA 460 Appendix A. Historical testing of similar products by others using these standards was largely targeted to seismic performance.

The Frost-ND team understood that a likely governing condition in Central Kentucky would be the initial unloaded condition of the rickhouses under lateral wind forces when frame connections would be more flexible – and potentially weaker – absent the load of barrels. Therefore, the Frost-ND team modified the test procedures to better represent the unique conditions faced by rickhouse owners in Kentucky.

Frost designed a schematic structural solution, designed and executed an experimental validation testing program, and completed a final structural design of the foundations and framing for two barreled spirit rickhouses, each with an approximate construction cost of $5 million. The rickhouse design not only offers high-density storage capacity but also has a distinctive feature where the 500-ton racking structure supports the building’s facade and roof. Working in partnership with the University of Notre Dame, Frost Engineering tackled a spectrum of storage and environmental hurdles at Rabbit Hole Distillery, devising a tailored, inventive and effective solution.