The University of Arizona’s Biosphere 2 (B2) is the world’s largest controlled growth apparatus dedicated to understanding the implication, mitigation and adaptation solutions for resilience of our planet (Biosphere 1) due to the global climate crisis. B2 is an Earth science facility that encompasses 3.14 acres and houses five synthetic ecosystems encased in a glass and metal spaceframe. Operational for thirty-five years and counting, these ecosystems include the world’s largest controlled analogues of tropical rain forest, desert, savanna, mangrove, and a million-gallon experimental ocean.

The Biosphere 2 Ocean (B2O) mesocosm—is dedicated to coral reef research—provides a unique opportunity to determine the impact of novel species interactions on ecological function. First, we can bring together species from across regions with minimal cost and risk compared to such efforts on natural reefs. The Biosphere 2 experiments are not bound by existing ecological associations or biogeographical constraints, allowing us to explore whether combining species differently can enhance resilience. Second, the unparalleled scale of the B2O system is crucial for replicating inter-species interactions needed to properly quantify these impacts on an ecosystem scale. Finally, state-of-the-art engineering upgrades facilitate precise abiotic control and simulations of realistic future environmental conditions (e.g., extreme thermal stress and elevated carbon dioxide). This precise control of the B2 mesocosm will allow us to test—for the first time—the resilience of restored species, and their associated microbiome in the face of continued warming and acidification.

The Biosphere 2 Ocean Life Support System project has been updating critical filtration and life support equipment to the B2O to create a coral reef testbed comparable to a natural coral reef ecosystem, serving as a community resource for fundamental reef research at ecosystem scale and reef restoration and resilience solutions. “Vintage” life support system equipment built in the 1990s was obsolete and torn out prior to 2018. Currently, bag filters protecting the heat exchanger are the only filtration equipment. An evaluation of the exhibit life support systems and water quality was done in 2017 with Hall Aquatic Design LLC. In 2018, TJP Inc., a design engineering firm focused on aquatic animal life support systems, has provided recommendations and schematic designs for the B2O life support system. These plans will be implemented in phases aligned with priority for proposed research.

This project consisted of three custom 60-ft long, 6-ft deep built-up and field-spliced pultruded FRP trusses with 24-inch-deep girt beams and cantilevered catwalks for utility support and personnel maintenance access.

As part of this important project, Frost’s scope of work consisted of developing the detailed design of FRP structural framing over the experimental ocean area to support supplemental lighting, based on a schematic layout design received from the Owner. All materials of construction are carefully evaluated to ensure they do not negatively impacted the experimental system. This project consisted of three custom 60-ft long, 6-ft deep built-up and field-spliced pultruded FRP trusses with 24-inch-deep girt beams and cantilevered catwalks for utility support and personnel maintenance access.

The total gross footprint of the new structures was approximately 4,000 sq. ft. Total project time was estimated at approximately 18 months to completion. The structures consisted of pultruded FRP framing members and stainless-steel columns, baseplates, and anchorage, the latter of which were designed to be moment-resisting as there did not exist enough clearance at the truss-to-column connection to detail a moment-connection as identified in a 3D BIM point cloud provided by the Owner. The FRP members are all Strongwell’s EXTREN® structural shapes. Frost was the engineer of record for the FRP structures and directed all major design decisions, including detailed vertical and lateral deflection analyses considering earthquake and thermal forces. Frost directed and/or reviewed the design of all of the aforementioned structural material components in compliance with the IBC with local City of Tucson amendments and the relevant provisions of ASCE 7, ACI 318, AISC 360, and ASCE 74.