Get into the
GROVE Hi g h Te c h To o l s P re s e r v e Natu re f or Futu re E s t at e / Mu s e u m
Get into the
GROVE
DEEP IN AN EXCLUSIVE DALLAS NEIGHBORHOOD ON A QUIET MORNING, A LASER SCANNING CREW GATHERED. THEIR MISSION? TO SCAN AND MAP TWO TRACTS OF LAND, INCLUDING OVER 600 TREES AND TWO BUILDINGS, TO MAKE WAY FOR AN ESTATE HOME AND PRIVATE MUSEUM. The land’s new owner had managed to gather something truly elusive in this part of Dallas: adjoining properties in a tony enclave, peppered with mature trees. Terra firma worthy of showcasing this art enthusiast’s future home and art gallery. Laser scanning or LIDAR, is a technology that works similar to RADAR. The crew from IKERD, a consulting company specializing in construction technology, set up equipment on the site. The team
dialed in their FARO portable laser scanners, a tool that measures rooms, objects and structures in 3D. The resulting high-resolution, 360-degree electronic images include shape, texture, size, relative elevations and spatial relationships. At first light, the young crewmembers set up their equipment and tackled their work with the same quiet efficiency they’d used on their morning WhataBurger. When the crew finished, they had collected data points to create a vast three-dimensional map of the 10acre site, which included the trees, as well as the two existing buildings targeted for demolition. THE BIG PICTURE The 3D map or laser scan of the project site is actually a series of scans, stitched together digitally. In order to stitch two scans together, you must have at least three common points between them, so the IKERD crew set up common points - plastic spheres and checkerboard targets throughout the site. These targets allow the software to calibrate the scan
Tomography, imaging by sections through the use of a penetrating wave, shows a visual representation of the density of a tree’s trunk, just below a large wound.
to the coordinates, so that the team could perform the scans in segments. Each segment took less than 10 minutes to scan and created a sphere of 3D data at a radius of 75-100 feet with ¼ inch accuracy. It was Sebastian Construction Group, a Dallas-based contractor known for having built some of the most luxurious and high profile estate homes in Texas that saw technology as the key to fulfilling the property owner’s wish to preserve as many trees as possible. Andy O’Nan, a preconstruction specialist with Sebastian frames the challenge: “The shortfall of a traditional survey is that it shows only the center point of the tree and doesn’t provide any indication for how it is growing. Trees are irregular by nature; they may grow at a significant angle requiring much more space on one side than the other. Large branches extend out at different angles creating irregular constraints. You can’t simply draw a circle around eac h tree as a “non-build zone” and accomplish the sort of design envisioned here.” PAGING THE TREE DOCTOR Enter board-certified master arborist, Greg David, another expert Sebastian recommended, to help protect the natural features of the site. Mr. David commented on the unusual nature of the undertaking and his role, “It’s exciting to get in this early on the project and preserve these trees. The roots of these trees extend way way out. Typically, when a contractor wants to save trees, he will draw a circle around the tree, and excavate around that, which doesn’t work because it destroys about 90% of the roots.”
A multilayer model of the trunk, made of the layers of data from individual sections, indicates the tree’s health.
The tree survey revealed about 15 to 20 different species across the site, mostly cedar elm, red oak, pecans, and
others. David assessed the red oaks at around 50 years old; the trees on the adjoining lot in the 70 to 80 year range, but possibly older. Initially, David provided general guidelines Greg David about feeder root and structural root diameters for the different species. Once the general building site area was determined, David assessed the 50 or so trees in the immediate vicinity and provided a report, outlining the life expectancy and detectable issues with each one. The rest of the trees were cordoned off in the protection zone. Together, Ikerd and David set up a matrix for laser scanning, using a radius-per-trunk diameter to determine tree root protection zones. The Sebastian team played coordinator for the data gathering projects and then handed the results off to the project’s design team, New York-based Thomas Phifer Architects. Armed with the 3D scan and the tree protection zone map, project architect Adam Ruffin could take up his part of the challenge: designing the structures to seem as if the landscape grew up around his contemporary design.
Get into the
GROVE
DEEP IN AN EXCLUSIVE DALLAS NEIGHBORHOOD ON A QUIET MORNING, A LASER SCANNING CREW GATHERED. THEIR MISSION? TO SCAN AND MAP TWO TRACTS OF LAND, INCLUDING OVER 600 TREES AND TWO BUILDINGS, TO MAKE WAY FOR AN ESTATE HOME AND PRIVATE MUSEUM. The land’s new owner had managed to gather something truly elusive in this part of Dallas: adjoining properties in a tony enclave, peppered with mature trees. Terra firma worthy of showcasing this art enthusiast’s future home and art gallery. Laser scanning or LIDAR, is a technology that works similar to RADAR. The crew from IKERD, a consulting company specializing in construction technology, set up equipment on the site. The team
dialed in their FARO portable laser scanners, a tool that measures rooms, objects and structures in 3D. The resulting high-resolution, 360-degree electronic images include shape, texture, size, relative elevations and spatial relationships. At first light, the young crewmembers set up their equipment and tackled their work with the same quiet efficiency they’d used on their morning WhataBurger. When the crew finished, they had collected data points to create a vast three-dimensional map of the 10acre site, which included the trees, as well as the two existing buildings targeted for demolition. THE BIG PICTURE The 3D map or laser scan of the project site is actually a series of scans, stitched together digitally. In order to stitch two scans together, you must have at least three common points between them, so the IKERD crew set up common points - plastic spheres and checkerboard targets throughout the site. These targets allow the software to calibrate the scan
Tomography, imaging by sections through the use of a penetrating wave, shows a visual representation of the density of a tree’s trunk, just below a large wound.
to the coordinates, so that the team could perform the scans in segments. Each segment took less than 10 minutes to scan and created a sphere of 3D data at a radius of 75-100 feet with ¼ inch accuracy. It was Sebastian Construction Group, a Dallas-based contractor known for having built some of the most luxurious and high profile estate homes in Texas that saw technology as the key to fulfilling the property owner’s wish to preserve as many trees as possible. Andy O’Nan, a preconstruction specialist with Sebastian frames the challenge: “The shortfall of a traditional survey is that it shows only the center point of the tree and doesn’t provide any indication for how it is growing. Trees are irregular by nature; they may grow at a significant angle requiring much more space on one side than the other. Large branches extend out at different angles creating irregular constraints. You can’t simply draw a circle around eac h tree as a “non-build zone” and accomplish the sort of design envisioned here.” PAGING THE TREE DOCTOR Enter board-certified master arborist, Greg David, another expert Sebastian recommended, to help protect the natural features of the site. Mr. David commented on the unusual nature of the undertaking and his role, “It’s exciting to get in this early on the project and preserve these trees. The roots of these trees extend way way out. Typically, when a contractor wants to save trees, he will draw a circle around the tree, and excavate around that, which doesn’t work because it destroys about 90% of the roots.”
A multilayer model of the trunk, made of the layers of data from individual sections, indicates the tree’s health.
The tree survey revealed about 15 to 20 different species across the site, mostly cedar elm, red oak, pecans, and
others. David assessed the red oaks at around 50 years old; the trees on the adjoining lot in the 70 to 80 year range, but possibly older. Initially, David provided general guidelines Greg David about feeder root and structural root diameters for the different species. Once the general building site area was determined, David assessed the 50 or so trees in the immediate vicinity and provided a report, outlining the life expectancy and detectable issues with each one. The rest of the trees were cordoned off in the protection zone. Together, Ikerd and David set up a matrix for laser scanning, using a radius-per-trunk diameter to determine tree root protection zones. The Sebastian team played coordinator for the data gathering projects and then handed the results off to the project’s design team, New York-based Thomas Phifer Architects. Armed with the 3D scan and the tree protection zone map, project architect Adam Ruffin could take up his part of the challenge: designing the structures to seem as if the landscape grew up around his contemporary design.
A 3-dimensional point cloud is being used for spatial visualization and orientation of different design concepts.
Get into the
GROVE The shortfall of a traditional survey is that it shows only the center point of the tree and doesn’t provide any indication for how it is growing.
With the design team located in NYC, the laser scan and tree analysis allows them to remotely test different design concepts and their fit in the natural landscape. HANGING WALLS One of the earliest design innovations was the decision to build the foundation for the new buildings on piers that can be moved in a 6-foot radius, should the preliminary design impact the roots of the tree. Contractors will hang the outer foundation wall to avoid trees. The architect brought in another expert, a structural engineer, to make this feature work. Sebastian will demolish two existing buildings on the site to make way for the new structures. They, too,
will use the laser scans to guide their demolition of the existing buildings without damaging the trees. Mr. David commented on the exacting nature of this task, “Some of the demolition is extremely delicate for the trees. The owner wants to preserve some magnolias for the art gallery. Some of the roots are impinging on the walls and foundations of the existing buildings. It’ll be interesting to see how Sebastian manages the demolition process. With the tree locations, the heavy equipment will have to be right against the trees.” The complex beauty of nature has long inspired artists. It’s fitting that this future art gallery will be built using modern technology to preserve it. ■
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