Each STB consists of a 3.125-inch-thick block of Neopor insulation foam held with high-strength bolted stainless steel rods between two end plates. Construction in the most difficult location CEICE, the Chinese construction firm building the EACF, is fabricat- ing, assembling, and then disassembling the structure’s components before shipping them to the Antarctic site for re-assembly. Because of the site’s remote location, forbidding environment, and short construc- tion window, all technical issues must be resolved prior to transport. “Not a single piece of structure can board the transporting vessel with- out being tested and approved,” Furtado said. In a BBC article, “How Antarctic bases went from wooden huts to sci-fi chic,” (www.bbc.com/news/magazine-38574003) Polar Journal editor-in-chief Anne-Marie Brady explained that, “Antarctic stations have become the equivalent of embassies on the ice. They are show- cases for a nation’s interest in Antarctica — status symbols.” For Brazil, that status is a byproduct of the country’s long-standing commitment to leading-edge environmental research for the benefit of all life on earth, reflected most recently by the EACF’s state-of-the-art design, advanced components, and modular fabrication a half-world away from its destination.
An architectural rendering of the Comandante Ferraz Antarctic Station. The upper block (left) will house cabins, dining, and living space, while laboratories and operations and maintenance areas comprise the lower block (right).
Thermal bridging typically occurs where structural steel beams or cast concrete penetrate an insulated building envelope. These penetrations conduct heat from interior support structures through the envelope, dis- sipating it into the exterior environment with three deleterious effects: • energy waste; • cold interior walls and floors, reducing occupant comfort; and • chilled interior surfaces adjacent to penetrations, forming condensation, potentially causing mold growth and rusting structural steel. Though problematic in any environment, thermal bridging conse- quences can prove particularly severe in Antarctica due to extreme interior-exterior temperature differentials and the difficulty of remedi- ating such problems in a harsh and isolated location. “To ensure that the building remains fully insulated from the outside, it was necessary to use thermal breaks in the connections of the raised structure to the steel columns in contact with the ground,” said Afacon- sult project engineer Rui Furtado. “We chose Isokorb STBs because they are multidisciplinary elements. First, they are a thermally insu- lated component, guaranteeing the continuity of the insulation even in the points in contact with the outside, as is the case with most of the column supports of the structure to the ground. It is therefore possible to have the building completely insulated from exterior to interior. “The STBs connect the steel structure and withstand shear force, tensile/traction, and pressure absorption, while dramatically reducing thermal energy loss,” Furtado said. “Another advantage corresponds to their modular construction. They work with all steel types and profiles and are constructed from non-rusting stainless steel, offering long- lasting corrosion protection. I also want to acknowledge the technical support given by Schöck, which was essential for this process.” The Isokorb Type S22 STBs used are load-bearing thermal insulation elements for steel structures that accommodate axial and shear forces.
Information provided by Schöck (www.schock-na.com/en-us/home).
An underside view of the floor-truss grid and the steel support system with Isokörb Type S22 structural thermal breaks installed to mitigate thermal bridging while carrying the structure’s weight and anticipated wind loads.
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august 2018
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