Posts tagged with "Precast Concrete":
Architectural sleight of hand transforms a FEMA safe room from bunker to glass box.Tasked with designing a community center on a shoestring budget, Des Moines–based ASK Studio was unsure how to fit the program to the project's finances. Then an attendee at a community feedback session suggested applying for FEMA funds to build a combination community room and storm shelter. The FEMA tie-in solved the money problem, but it created an aesthetic challenge. The architects had originally diagrammed the community center, sited atop a central knoll in a large park in Urbandale, Iowa, as a connection point that would orient visitors without obstructing views. When the project was redefined as a safe room, said ASK's Brent Schipper, "I just cringed, because how do you have a transparent node that's also a tornado shelter? I thought, 'We're going to make a bunker, and pretend it works as the node of the centerpiece of the park.'" Luckily, Schipper's gut reaction proved wrong. A triumph of architectural sleight of hand, ASK's Giovannetti Community Shelter is built evidence that "welcoming safe room" is not an oxymoron. The modified program in place, the architects began by asking themselves, "How do you achieve transparency when all you have is concrete walls?" said Schipper. They turned first to the roof line, adding a sense of weightlessness with a broad overhang above a picnic area. Though not part of the shelter function—it would likely shear off in the event of a serious storm—the overhang plays an important role in the structure's aesthetic identity. Thanks to the canopy, "there are parts of the building that are light," said Schipper. "You can't tell it was a concrete box." A second gesture further forestalls any temptation to identify Giovannetti Community Shelter with Cold War-era bunker architecture. A glass storefront (again not included in the shelter program) encloses the walkway connecting the shelter room to the rest of the park. "When you use the building, you're always circulating in the corridor, so you're always visually connected to the park," said Schipper. "The glass belies the fact that the room you were just in is a storm shelter." The curtain wall also defines the building's exterior appearance, particularly on the south side. "What you see from the south elevation is a mostly glass structure with these very minimal roof lines," said Schipper. The tornado shelter itself was constructed from a 12-inch-thick precast concrete roof and wall panels. To keep the room from feeling too closed-off, ASK initially sketched in storm doors between the protected space and the glass corridor. Then the architects heard about Insulgard, whose tornado-safe windows had recently received FEMA approval. The architects ditched the door idea and instead installed safety windows (approximately 1 1/2 inches thick) on both the exterior walls and the wall between the shelter and the corridor. "[The design] would not have worked if you were in that room and you never had any glimpses of the outside," said Schipper. "I was amazed by the technology of the storm windows." Though ASK faced several challenges in designing the Giovannetti Community Shelter, none of the firm’s solutions were overly complicated. "In the end, it's a very simple parti," said Schipper. "We were staking all of the drama, all of the messaging, on two moves: the overhang of the roof, and the transparency of the glass facade. When you back away, it's like, 'you only did two things.' But those two things are particularly unique to the fact that it's a tornado shelter."
A tight budget and short timeline inspired an innovative concrete and terra cotta facade.BNIM and Moore Ruble Yudell approached the design of the Henry W. Bloch Executive Hall for Entrepreneurship and Innovation at the University of Missouri-Kansas City with two objectives. The first was to express the creative spirit of the university’s program in entrepreneurship, which at that point lacked dedicated support spaces. The second goal was to tie the contemporary structure to its historic surroundings. Moore Ruble Yudell, who developed many of the project’s interior concepts, tackled the former, creating flexible classroom and laboratory spaces and a multi-story amphitheater that doubles as casual seating and a venue for school-wide gatherings. As for the latter, BNIM designed a multicolored terra cotta envelope that balances singularity with connection. “The idea was to create a building that sat by itself, but somehow bring it into context in terms of materials,” explained BNIM senior project architect Greg Sheldon. Because so much of the existing campus architecture featured masonry construction, the architects “had a desire to use a fired earth material, but to try to do it in a more contemporary way,” said Sheldon. Inspired by a project in London that combined different colors of terra cotta to blend it into its surroundings, BNIM began working with architectural terra cotta manufacturer NBK to design a rain screen for Bloch Hall. But budget and time constraints soon intervened. To cut costs and enclose the building as quickly as possible, BNIM approached Enterprise Precast Concrete about the possibility of casting the terra cotta components directly into insulated concrete panels. “There was a lot of back and forth between Enterprise Precast Concrete and NBK,” said Sheldon. “This was one of the very early projects to use this technique.” To further streamline construction, BNIM and Moore Ruble Yudell decided to integrate the concrete into the interior aesthetic, so that the inside face of the panels required no additional finishing beyond sandblasting. General contractors JE Dunn Construction “loved that if we could pull this off, the insulation’s in place and the inside’s finished,” said Sheldon. “They bring it out, put it on the building, and that’s it.” For glazing, the design-build team ordered a YCW 750 XT high performance curtain wall from YKK, sized to slot into the opening between the building’s masonry components. Together, the insulated concrete-terra cotta panels and high performance glass helped put the building on track to earn LEED Gold certification. The patterns in the terra cotta “weren’t accidental, but were studied and studied,” said Sheldon. The south end of the building is a deep red, like the adjacent Bloch School Building. To the north, the colors fade to a buff yellow, reflecting the lighter tones of the nearby student center. To perfect the patterning, the designers first looked at the range of colors available through NBK and chose the six most compatible with the surrounding buildings. They then unfolded the elevation of the building and plugged the different shades into their digital model. BNIM experimented with different combinations, printing each and pinning it to the wall before making adjustments. “I don’t know how many iterations they did,” said Sheldon. “It just went on and on.” The final scheme achieves the desired effect. In color and materials, it creates a dialogue with the older buildings around it. Yet the bold patterning simultaneously marks the facade as a 21st century creation. Upon receiving the $32 million gift from Henry W. Bloch that made building the new Bloch Hall possible, then-Dean Teng-Kee Tan observed that “the path of innovation is never a straight line.” The architects manifested the analogy in the building's architecture and landscaping, carving the interior into a series of curvilinear spaces, and connecting the building to its neighbors via a meandering path. But the statement applies equally to the design process itself, in which a tight budget and 14-month construction timeline encouraged an innovative combination of concrete, terra cotta, and high performance glass. A successful sublimation of limitations into opportunity, the story of Bloch Hall’s envelope is the story of entrepreneurship in microcosm.
A digitally-designed medical products showroom plays well with its City Beautiful neighbors.The Global Center for Health Innovation, designed by LMN Architects along with the attached Cleveland Convention Center, is more than a showroom for medical products and services. Located adjacent to the Burnham Malls, the open space at the heart of Daniel Burnham’s Group Plan of 1903, the building is part of Cleveland’s civic core. “One of the things about the Global Center is that it has a unique expression and in particular the facade treatment,” said design partner Mark Reddington. “But it’s also a really integrated piece of a bigger idea and a bigger composition.” A dynamic combination of textured concrete panels and irregular slashes of glazing, the Global Center’s facade, which won honorable mention in AN’s 2014 Best of Design Awards, deftly negotiates the gap between the building’s historic context and its function as a high-tech marketplace. The Global Center’s City Beautiful surrounds influenced its facade design in several ways. “Part of the trick for us in looking at the Global Center,” said project architect Stephen Van Dyck, “was to try and make a building that was contemporary and relevant, but also a building that referred and deferred to its context materially and compositionally.” As a reflection on the solidity of the older structures ringing the Malls, the architects minimized glazing in the east face’s concrete system. In addition, they chose the color and aggregates of the concrete to mimic the tone of limestone. The texturing on the concrete panels, too, was informed by the Global Center’s context. “Like the classical buildings, there’s a lot of detail that shows up in different lighting conditions,” said Reddington. At the same time, the Global Center is very much a product of the 21st century. “There was an explicit intention in creating a facade whose qualities would not have been achievable without digital technology,” said Van Dyck. “It doesn’t look like it was handcrafted. It was primarily an exercise in allowing the technical means of creation and design to live forever on the outside of this building.” In particular, he said, the architects were interested in how their chosen material—precast concrete—allowed them to move beyond a punched-window system to a more complicated relationship between solids and voids. The result eventually became a scientific metaphor, as the designers observed the resemblance of the pattern to the twisting helices of a DNA molecule. LMN developed the facade design on a remarkably short timeline: about four months from concept to shop drawings. “The schedule requirements of the whole thing were absurd,” said Van Dyck. To make modifying the design as easy as possible, the architects developed a utility called Cricket to link Grasshopper and Revit. The ability to update the BIM model in real time convinced the design-build team to take risks despite the compressed timeframe. “Once they realized there was a strong mastery of the data, an ability to listen and incorporate the needs of [multiple] parties, that was really the breakthrough,” explained Van Dyck. “They said, ‘Hey, we can build something that’s a little unconventional.’” Besides their Cricket plug-in, a 3D printer was LMN’s most valuable tool during the design process. To explore how the panels’ texturing would animate the facade under different lighting conditions, they created plaster models from 3D-printed casts. “We had to do that because the geometry was so complex that we didn’t have any computers at the time that were capable of [modeling it],” said Van Dyck. “For us, working between the physical, digital, hand-drawn renderings were all so critical in discovering what we ultimately ended up building.” Sidley Precast Group fabricated the concrete panels with a surface pattern of horizontal joints that vary in depth and height. To minimize cost, the fabricators made almost all of the molds from a single 8-by-10-foot master formliner, with horizontal ribs spaced every 6 inches acting as dams for the smaller molds. While LMN Architects originally wanted to limit the number of panel types to eight, the final count was around 50, including larger pieces made by connecting smaller panels vertically. The approximately 400 precast panels were moved by crane to a system of vertical steel tubes running from slab to slab, then welded into place. The Viracon glazing was welded to the same tubes, a couple of inches back from the face of the concrete. The large atrium window on the building’s east face was manufactured by NUPRESS Group. For the architects, the significance of the Global Center’s facade remains tied to its broader context. Its design, while driven by modern technology, achieves a surprising degree of harmony with its surroundings. “Our building is in a way very classical, though it wasn’t an explicit intention of ours,” said Van Dyck. “To create a language that was both universal and also something that was really new—from our perspective that was a big achievement of the project.”
Barkow Leibinger designs a precast folded facade that puts a gentle spin on surrounding traditional architecture.On one of the last urban tracts of available land in Berlin, Germany, local architecture firm Barkow Leibinger recently completed an 18-story tower, Tour Total. Highly visible from a neighboring train station, and the first completed project in the site’s 40-acre master plan, the tower has a raster facade with precast concrete panels that were geometrically computed in Rhino to create twisting inflections, conveying a sense of movement around the building’s four sides. As a load-bearing facade, 40 percent of the surface is closed, and 60 percent is triple-glazed, with every other window operable. In addition to integrated energy management strategies—the first building tenant is French energy company Total—partner Frank Barkow said the firm’s extensive background in digital fabrication and research allowed the efficient development of the dynamic facade. Drawing from the surrounding, traditionally quadrilinear brick facades of the 1920s and 30s, the tower’s lines are imbued with an engrained depth that twists optically to read differently in direct sun or cloudy weather, without actually moving. The design team drew a series of T-shaped elements to create the exterior components, and K-modules for structural stability. “The folding K modules produce an in-and-out for continual diagonals that wrap around the corners,” Barkow told AN. Interior and exterior concrete components sandwich around glazing, windows, and insulation. To test the design, 3D models were fabricated on a CNC router. Many of the profiles in the facade assembly are repeated many times, though 160 are unique. Each cast could be used at least half a dozen times before another had to be fabricated. German fabricator Dressler milled plywood molds and white concrete was poured over an affixed release surface. Once solidified, each section was finished with an acid wash to expose the aggregate and transported to the building site. Steel pins, embedded within the structure’s poured concrete floors, connect the layers of the facade sandwich. Barkow and the concrete contractor had several discussions about eliminating an interior precast layer in combination with an Isokorb thermal break to mitigate expansion but, in the end, opted for the original design. “It’s the next technological step, for the facade to work like an exoskeleton, but we’re a few years away from that,” Barkow said. Despite budgetary and time restrictions, the LEED Gold-equivalent Tour Total was realized successfully, in part, through parametric design and advanced fabrication methods. “We’re taking advantage of northern Germany’s extremely proficient building culture and working with our fabricators here and in Switzerland as early as possible in the design process,” said Barkow. “There’s a lot of back and forth where we push them away from conservancy and they push us towards efficiency.”
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A new cultural focal point takes shape in DallasWhen the Dallas Museum of Nature & Science was created from the 2006 merger of three city museums—the Museum of Natural History, The Science Place, and the Dallas Children’s Museum—the new institution set its sites on expanding programming with a new facility in the city’s Victory Park neighborhood. Now, the 180,000-square-foot Morphosis-designed Perot Museum of Nature & Science is slated for completion in 2013. Located at the northwest corner of Woodall Rodgers Freeway and Field Street, it marks the future crossroads of the city’s Trinity River Corridor Project and the city’s cultural districts. Floating atop an irregularly shaped plinth that will be the base for a one-acre rooftop ecosystem, the museum’s striated concrete facade offers a first glimpse at the dynamic transformation of the site. Early renderings show a smooth monolithic cube as the museum’s main volume, but the Morphosis team began working with the Hillsboro, Texas, branch of Gate Precast early in the project to develop a horizontally striped precast concrete panel design for the facade. “They wanted something different from everything else in Dallas,” said Gate sales and marketing manager Scott Robinson. “The architects wanted it to be true, raw, and modern.” To this end, Morphosis selected a plain gray concrete mix, without pigment or white cement, for the facade, knowing there would be natural mottling to each panel. “They didn’t want the building to look painted,” said Robinson. In total, the company will fabricate 655 precast pieces for the project. Gate created a series of mock-ups using random combinations of convex and concave shapes that would flow seamlessly from one panel to the next. After refining the design in Revit, Gate’s BIM operators modeled more than 100,000 square feet of precast cladding on the museum’s exterior for Morphosis’ 3-D models. Wood-framed concrete molds constructed in a range of set dimensions (the average size is 8 by 30 feet) helped keep facade costs lower. Within these, convex and concave rubber pieces based on the team’s digital models can be placed to achieve the desired striation. In the harsh Texas sun, the random shapes cast bold shadows across the building’s elevations, gradually giving way to smooth concrete surfaces on the higher levels. Because the pattern continues at the building’s corners, end panels required a two-step process: The short end was poured and set first, then rotated to allow the long section to be poured before the two pieces were attached with a cold joint. The curved precast panels for the museum’s base created another challenge—building formwork in multiple axes. Gate’s engineering department created a series of geometric points and calculations for its carpentry wing, and carpenters built the formwork by hand without any CNC equipment. “The hard part is that they get a picture of what the panel looks like, and they have to build the reverse of that,” said Robinson. The curved precast panels will require nearly 80 unique molds in all, comprising about 15 percent of the project’s precast concrete. For its final contribution to the project, Gate will cast several pieces that Morphosis is referring to as “sticks”—long precast beams that will decorate the site as sculpture or functional elements once the new museum’s rooftop ecosystem, with landscape architecture by Dallas-based Talley Associates, is in place.