This lecture was presented at the 3D Digital Documentation Summit held July 10-12, 2012 at the Presidio, San Francisco, CA
Foamhenge: 3D Modeling and Conservation of a Monumental Sculpture
Novel use of technology, 3D digital documentation, model-based engineering, contemporary materials and techniques illustrates the potential that digital documentation and technology has in supporting creative and collaborative problem-solving. A recent project to conserve an important monumental sculpture in GSA’s national fine art collection “c” by artist, Dimitri Hadzi, for relocation required by a major renovation of a mid-century high-rise federal building offers a good example.
Creative and environmentally-responsive problem solving is often viewed as doing more with less. With the convergence of tools like laser documentation, 3D modeling and new conservation techniques, we can now benefit from accurate data and contributions from diverse perspectives – information for decision making – which result in greater opportunity for preservationists and conservators to improve treatment of the important works under our care. The unique challenge of caring for “River Legend” demonstrates how this opportunity fulfilled immediate challenges and allowed our team to establish a more expansive goal: to retain as much original integrity as possible. This is evidence of the enhanced benefit that these new technologies and processes, when collaboratively and creatively applied, offer.
“River Legend” is a massive 20 foot tall stone arch created by the late artist in 1976 from five huge sections of columnar basalt. The stones were selectively-tooled, gravity-set, pinned and installed on-site in a plaza as part of the original construction of the Wyatt Federal Building in Portland, Oregon. Two years ago under the American Recovery and Reinvestment Act, plans for the complete renovation of the building to modernize and meet GSA’s high performance/green building goals called for temporarily relocating the monumental archway to make way for the base of the construction tower crane. Under the leadership of the chief architect, a collaborative team of art conservators, fine art specialists and design engineers set a goal of executing the move without affect to the work’s original integrity despite the lack of input from the artist or access to original documentation. Initial site analysis, subsequent laser scan data and 3D modeling were important contributors to the artwork’s condition assessment – informing our treatment plans. Our data indicated that removal by disassembly would require saw-cutting the artists original hand-tooled hairline joinery, loss of much original material and would have resulted in an unacceptable material change in the appearance and geometry of the original artwork.
Our team chose a challenging path, one that depends on greater dimensional and volumetric accuracy, reduced unknown conditions, more confident risk assessment and offered participants broader data access fostering interactive problem-solving. These are the new opportunities that 3D/BIM modeling technology offers preservationists and conservators today. Our resulting conservation approach, employing high-strength space-frame jig, rigid foam encapsulation and new concrete cutting techniques, was direct, boldly innovative and visually dramatic. Its success offers an elegant solution for a complex problem, broadening the value of digital data documentation and can be applied to the work and future development of conservation techniques by others in the field.
Swett: I want to suggest further that it’s the use of digital documentation in this quick case in the conservation of a monumental sculpture as part of GSA’s national fine arts collection that this is just one aspect of a broad revolution in terms of taking data, which normally was interpreted by those who had the expertise to interpret the 3D from the 2D and make it available for all parties.
A little bit about GSA, the public building service owns and operates and leases for its agency clients, buildings around the country, arranging from historic buildings through the mid-century modern and then into the contemporary, examples here in Alaska with stripped down modernism of the Ketchikan federal building in Boise, Idaho, in the lower left, the federal building, the courthouse which I think in Idaho, is one of the most significant modernist buildings in that state if not in that region. Then some more contemporary buildings on the right here with the federal building in San Francisco, Thom Mayne’s project. All of these account for a portfolio of over 350 million square feet of rentable space in more than eight thousand properties.
One of the significant advantages of having a large portfolio, a large interest in real estate is being a leader. The GSA has that in terms of sustainability signing on early to the LEED process and early on putting on 44 LEED projects into certification. More of our historic properties here, another strip down modernist piece on the upper panels with the Anchorage Federal Building and below our earliest, in our region at least, historic building, the pioneer courthouse, which frames one edge of the living road in downtown Portland, if you have been there. You see on the far right a couple of images one of a lead laid LiDAR scan and a point cloud, and then a finished texture mapped 3D model of the building. That’s the current process. We are undertaking a full documentation of that building, as it is our singular national historic landmark building but it’s also a very at risk building in the sense that it’s stone surface exterior is always subject to wear.
Moving into the realm of arts and one of the areas that have been significantly interested in that’s in my role, is the fine art collection. I’ll just pan through a number of these shots of significant pieces in our collection. Here is some of the Northwest, the recently completed “Non-Sign II” by Lead Pencil Studio a significant site specific artwork. Most of the works we do are site specific or building specific at the very least. In this case at the Eugene Federal Court House, another Thom Mayne project that is known for the integration of the art and architecture significantly. There is more art here in Orlando, Florida. And then, of course, our earlier pieces that are significant to the national culture heritage as well, in terms of early pieces that were either murals or sculptural pieces. There is a recent piece and again in Seattle, with the Seattle US Courthouse, by Michael Fajans.
I want to talk today about the art, but I want to reflect on the project that prompted this conservation process, that’s a Edith Green Wendell Wyatt federal building, which is undergoing a significant renovation. It is currently a very important change to the Portland skyline with a series of sustainable strategies that take a very poorly performing mid-century modern, basically a speculator office building and improving it to the point where it’s going to be one of the more sustainable buildings in terms of high rise developments, in terms of air conditioned buildings in the nation. We’re hoping for lead platinum on this one. The building, as I said, is in downtown, it is a significant piece, and it is adjacent to a number of parks. You can see here on the upper left, park spaces, so it is part of a civic center development that is kind of a bright green element in downtown. You can see here some of the current ongoing construction, where we have the sloped glazed PV panel array at the roof and then the re-did vertical aluminum extrusions, which will act as a breeze soleil on the south and southwest exposures. Day lighting strategies involving cutting into existing slabs and bringing day lighting into otherwise darkened spaces, all leading to a much more tolerable workplace for the federal employee.
Here I want to talk about the actual artwork involved in the conservation. What prompted it primarily is that the location of these sculptures really was in the way of the ideal location of the construction tower crane. We needed that scale of work to execute the scale of renovation that the building was going to undergo so that’s what prompted the move.
Further, we evolved a strategy that made a much more significant challenge for ourselves involving River Legend which is the sculpture that we are moving. Understanding that we have the tools at our disposal with 3D modeling and laser documentation to go a step further in terms of the level of care that we might employ as we look at the sculpture, which was created by and artist who had passed away, and we had very little access to documentation and construction detailing to suggest how the arch, in this case the monumental arch, was constructed. What we did understand from letters from the artist and from talking with his wife, who continues to operate his studio in his legacy, is that there was quite a bit of effort at the time of its installation on site to handwork all of the joinery and the five pieces that make up the entire assembly. This is the artist and his significant contribution to sculpture in the modernist period.
River Legend is named such because of a Native American legacy which suggested that there was a natural bridge over the Columbia River at the gorge, a significant river. The legend was the takeoff point for the artist to suggest a memorial to that legend and to the native tribal origins of the Pacific Northwest.
Working with the teams we convened an onsite meeting to discuss how we might move the piece, and it was suggested that we look at ways that would retain as much of the significant artist fabric as the original, which was a challenge because the joinery was basically created handwork and was hairline joints, pinned together sections. This led to the use of and here is an early structural sketch that we found in our files to suggest how the piece was pinned and installed. It’s about mounted at its feet on basically pads of grout and then doweled into the concrete deck. Here you can see a texture map, a 3D scan. That was important for us in terms of not only finding the extent and shape of the artwork but also to understand its actual weight. The piece was created in Columbia Basin basalt, basically both hand worked and natural finished faced stone.
The concept we arrived at was to move the piece in its whole and intact. And so we embarked on a series of tests and models, using the scan data and a 3D wireframe of the jig or the rig that would be used to move the piece. You can see some schematics here of the typical nodes, of the construction of the armature or the jig that we were using to contain the piece, as we were to lift it. You can see that the lift had to occur on a dual drum crane which allowed us to tilt and lift as we were looking to effect a progressive removal from the site without endangering the workers below. Later on that will be important as we reattached the feet and the structure that will be needed to reposition the piece. So the scanning process using, at that time, state of the art but now today it is much smaller.
The first test was a mock up using pipe. In the final form we used high strength custom designed nodes and spans, but we wanted to test the concept using a stretch wrap protection over the piece. Here another piece of basalt just used as a model and then foamed in to the rig using expansive polystyrene two-part foam and then a drop test to see how much the effect might have had on the piece. This project actually fulfilled two of my personal goals, one of which was to wear a bunny suit, yeah, and the other one was to as an architect, was to have an unnatural act with an arch. I mean really, this is taking an arch and flying it. It fulfills one of my fantasies anyway.
You can see here the assembly process on site where the subparts were preassembled, fit around the piece, and as we got closer to the piece we worked within to add supplemental struts. Each of these were designed to fit the surface location as closely as we could using that model. The main components of the structure are universal, that is they can be reassembled, de-assembled and reused. That was a sustainable issue that we wanted to fulfill as well. The foaming process and then ultimately the cut where the piece was released from the deck in which a chainsaw type concrete saw was used allowing us to free it from the deck, lifting the piece up over a patch of mature trees and releasing it from the site and then transporting it to a warehouse.
The artwork, as you can see, is a fairly monumental scale. It weighs 12 to 14 thousand pounds. The intent here in October, is to begin a process of returning after housing the piece. We have a little animation showing the point cloud model being used as a device to look at locations. The locations potential for the site because the redevelopment of the site meant substantial modifications. Let me just briefly say that the intent was to replace the piece in its original location. In fact, what we found in reading correspondence between Skidmore’s architect and the artist, we discovered that the piece was actually not located per the artist’s wishes, and indeed we’re looking at an alternative location and that’s also prompted by the change in the site plan as a result of that substantial impact of the vertical breeze soleil coming down onto the site. So, we are going to be looking at several potential places, using arts experts in terms of an art panel that we are assembling to discuss the new location for the piece. Once that’s done it will simply be a matter of reversing the process.
Thank You so much.
B. Story Swett joined the General Services Administration as Regional Chief Architect for the Northwest/Arctic Region in 2004. Mr. Swett oversees regional Design Excellence programs for the real estate provider to federal agencies in Alaska, Idaho, Oregon and Washington.
Swett serves as advocate for design excellence for the Public Buildings Service, heading regional offices of the Chief Architect, the Fine Arts and Center for Historic Buildings.
Before joining GSA, Mr. Swett, a registered architect for over 25 years, practiced preservation architecture and served as member of the Landmark Preservation Commission in Denver, Colorado.
Widely traveled, hugely curious and innately collaborative, Mr. Swett is dedicated to design and arts innovation, fostering 3D/BIM processes for preserving and enhancing our built environment.