A Well-Crafted Connection

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Rockefeller University’s $4.8 million Collaborative Research Center project is expected to do more than repair and modernize two aging research facilities. A parallel goal is to create an environment that facilitates and stimulates connections between scientists, researchers and staff that work in the two facilities.

To help achieve this vision, the Mitchell/Giurgola architectural firm and Turner Construction conceived a sweeping 8-level, glass bridging building that brings the historic limestone and masonry Halls together using vertical circulation areas. The bridging building incorporates floor-to-ceiling windows that take advantage of natural light and sweeping views of the East River. Inside, architects called for a metal structure with wood slats throughout the hourglass-shaped interior atrium to create an organic feel that melds with the outside environment.

Unfortunately, early estimates for the metal/wood design elements exceeded the allotted budget, giving Eastern Millwork, Inc. (EMI), a New Jersey-based custom architectural millwork fabricator, an opportunity to demonstrate an innovative connection of its own–the collaborative potential of interconnected BIM-to-field solutions with expert engineering–all while cutting the cost of the atrium design elements in half.

BIM adoption
For more than a decade, EMI has worked to expand and streamline its CAD CAM connection in an effort to further the automation of its production processes.

Andrew Campbell, president of EMI, says, "Like many other specialty trades in the construction industry, globalization and the competitiveness of lower cost labor now vie for a share of our market. We must continually find ways to stay competitive and deliver value through ever more improved automated processes."

Over the years, EMI has extensively leveraged Auto CAD 3D programs coupled with custom parametric scripts and a proprietary bar code drive production system that links concept to fabrication.

With the advent of building information modeling (BIM), the firm quickly recognized the parallels between its production and the project production. "BIM techniques are all about eliminating costly rework and reengineering in the field and, thereby speeding up the construction process," says Campbell. "The industry move to BIM expands the envelope of information control, facilitating greater collaboration and automation of not only the production process, but the information process. Through this improved control, we can rethink the building process and the way we deliver a project."

The next step was to find a way to improve the transfer of data from the field to the 3D model.

Enabling the jobsite
At the start of any project, EMI must replicate field scope and conditions in the 3D environment. For years, the firm relied on strings and chalk lines to gather the necessary data from the field. The early scoping effort typically a time-consuming process that involves significant time gathering data at the job site and additional time back in the office translating that data into EMI’s design software. Because of the hand data gathering processes, there are often problems with inaccuracies once the engineers move to install the custom components at a project.

Not long ago, Campbell was on a jobsite and saw a subcontractor using a robotic layout solution to locate hangers and pipes for a mechanical system. He noted a lot of symmetry in the contractor’s need to collect and connect positions that must tie to a digital model.

After a call to Trimble, EMI purchased a single Trimble LM80 Layout Solution. The robotic layout solution from Trimble lets EMI’s crews gather data in the field quickly and easily, helping them design and construct the seemingly impossible for less cost.

He adds, "If BIM is analogous to the written word that communicates an idea, then Trimble’s LM80 is the printing press that deploys that message to those interested in `reading’ the content. This technology connects the reality of field conditions with the model, translating what is in the model to the onsite craftspeople through robotic layout functions and delivering unprecedented precision in an automated function."

The BIM-to-field connection was put to the test on the Rockefeller Collaborative Research Center.

Wood possibilities
The Rockefeller Collaborative Research Center is situated on the northeast corner of the university’s 14-acre campus on Manhattan’s Upper East Side. The bridging building is constructed over a parking lot. It incorporates conference and meeting rooms, restrooms and food service facilities as well as the central ellipsoidal atrium.

Originally, designers called for the atrium design to incorporate a metal structure with wood ribs. It would have been very challenging to keep the wood ribs level around the atrium’s ellipse and require very precise metal to wood connections with every position at a different angle.

Campbell says, "Instead, we suggested eliminating the metal framework and prefabricating large wood panels that could be installed at designated positions of the structure.

After some analysis of the concept’s structural integrity, the Eastern Millwork team built a mockup. The client loved the look and awarded EMI a design/ build lump sum contract to complete the rest of the atrium design.

"We knew we could use the LM80 to define 3D positions along the sloped concrete cylinder to mount panel support brackets," says Campbell. "We had one of our engineers create a script in AutoCAD that would draw the model and generate the information required to fabricate the parts."

EMI engineers also developed script routines in AutoCAD that prepped the design file by adding field points that could be easily interpreted by the Trimble LM80 field software. Once the data was transferred to the Trimble field software, EMI engineers could precisely stake the attachment points.

Campbell says, "Keep in mind, we needed to perfectly locate the wood panels in space–not to a hard point. We located concrete edges and adjusted the model as much as possible to position the brackets that would support the panels. The brackets were to be mounted to the edge of sloped slabs on radius."

Throughout the process, the general contractor combined EMI’s model with the other models developed by the various project team members to coordinate connections, clashes and construction processes.

"The BIM strategy affords people to make corrective action earlier in the game and eliminate costly rework during construction," says Campbell. "In the case of the research center, the combination of skilled experts with this BIM-to-field connection allowed us to deliver a product that exactly met the customer’s specifications."

EMI fabricated and installed the architectural millwork, including a complex atrium design. The first phase of Collaborative Research Center project, which includes the renovation of Smith Hall and the construction of the bridging building, was completed in early 2010.

Beyond academia
EMI has continued to derive benefit and competitive edge from its BIM and fieldbased connectivity on projects that range from sports arenas to performing arts theaters. Its production process is now completely BIM-driven. Information flows from the field to the model to the fabrication machines and then back to the field, allowing
the company to find the most effective and efficient way to complete a project.

Campbell concludes, "The space between the design development and the deployment is becoming tighter and tighter. The ability to drive the information flow from the field to the model to the machine-driven automated process and back to the field is a reality–and within that reality, we are able to deliver our customers unprecedented value."

Vicki Speed is a freelance writer based in Denver, Colorado.

A 1.568Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE