Last December, ground was broken for the Carl R. Darnall Army Medical Center at Fort Hood, in Killeen, Texas. The $534-million, 947,000-sf project will replace the existing medical center, which was built in 1965, and increase the number of patient beds in the facility from 128 to 151. It will also have much larger operating rooms than the old facility, a six-story hospital tower, three outpatient specialty clinic buildings, and three parking garages.
The U.S. Army Medical Command and the U.S. Army Corps of Engineers are developing the new medical center as a design-build project from the Building Team of Dallas-based HKS and Wingler & Sharp of Wichita Falls and joint venture design-build contractor Balfour Beatty/McCarthy of Dallas. The USACE awarded contracts to these entities in great part due to their fluency with 3D building information modeling and their ability to meet USACE’s requirement for all of its design-build projects to employ BIM. The project is scheduled for a 2014 completion; LEED Gold certification is the goal.
What makes this project intriguing has to do with one particularly unusual and effective arrow in the collective Building Team’s digital quiver: an ultra-high-tech workspace that whose purpose is to enhance early BIM collaboration, reduce problems during design and construction, and enable more than 40 members of the Building Team to coordinate their work on the project’s Autodesk Revit model early in design.
BRINGING VIRTUAL REALITY DOWN TO EARTH
The HKS Virtual Theater is housed in HKS’s Dallas office. The 864-sf facility—affectionately called the “BIM BAM! Room” by the Building Teams that use it —is equipped with the latest generation of Smart Technologies: interactive whiteboards, three HP Z400 workstation computers linked to a projector, and two hookups for laptops. The three in-room computers are connected to HKS’s high-speed network and are loaded with the latest BIM design software, including Revit, Navisworks, and several architectural visualization programs such as 3Ds Max.
Balfour Beatty/McCarthy currently has two estimators and the BIM manager on the project co-located in the Dallas office with their design team. While there are large-group meetings once a week with more senior members of the team, many integrated design and construction questions are resolved on a daily basis by a group of four or five.
Using the Virtual Theater, architects, operations personnel, design managers from the construction side, and even some design-assist subcontractors are all using tools such as Navisworks and the Smart Board to make modifications directly on the shared BIM model. In the past, these changes would have been made on paper and sent back to the architects. By putting everyone in one big room, the Building Team has found that they could make this process much more efficient. Technical problems that previously would have taken a week or two to isolate and rectify can now be handled in three or four days.
“Most of our clients on projects of this magnitude, if they’re not already requiring BIM, they’re strongly suggesting it,” said Noel Barrick, HKS’s principal-in-charge on the Fort Hood project. He says the Building Team has completed structural and exterior skin clash detection and has held an MEP session that started the first below-grade packages through level-one slabs. Also in the works in the Virtual Theater: a review of the utility plant.
HKS Associate Principal John Bienko said the design team has identified where conflicts exist in constructability during the design phase. “These are the kinds of normal conflicts that occur among trades and disciplines,” Bienko said. “We’re just getting to them earlier. Many are straightforward fixes. It’s just getting people out of their silos and working collaboratively.”
A multiphase design-build project such as the Darnall Army Medical Center truly benefits from BIM and integrated delivery. That’s because, while construction has already begun on parts of the project, design continues on the remainder, pushing the Building Team to meet design deadlines that are not as easily measurable as their construction goals.
However, this discontinuity can have an impact on how the designers in such government projects are compensated. “In construction, you have your schedule of values that you can physically measure to show when you’ve completed, say, 45% of the project,” says Eric Burk, director of preconstruction services at Balfour Beatty. “In design it’s much more difficult. We’re paid by the government by design phase, but with BIM it’s become an issue to define how we’re able to measure design time.”
The Building Team asked the USACE for a monthly payout based on progress shown in the Revit model. “We thought we could give them a CD each month to show them where we were,” but the Corps of Engineers balked at the idea. “They said it wasn’t in our contract,” he laments.
GETTING BURIED IN PAPERWORK
Burk says the Building Team members and the USACE are making a goodwill effort to figure out new ways of working together but are being stymied at times by federal requirements for design practices that don’t seem to keep pace with the kind of high-tech BIM design technology being used at Fort Hood. The federal overseers for the Darnall Army Medical Center required the Building Team to submit 2,700 sheets of construction documents and another 2,000 pages of narrative just for a preliminary explanation of the design, not even including design specifics. Had they been able to share a BIM model rather than using paper, the Building Team would have saved a lot of time, not to mention trees.
In design-build projects like this one, government staff would normally take two or three weeks to pore over the paperwork, make design comments, and send them back to the Building Team to review and report back. Not so in this case. “When you’ve got the BIM model as early as we had it, the coordination is done at an early stage,” said Burk.
The federal officials didn’t believe that the mechanical systems were already coordinated with the structural component on much of the project. “They thought it wasn’t possible,” says Burk, acknowledging that he could understand why: “The model is huge—more than a terabyte when all the packages are in there.”
To convince the federal officials of the BIM model’s efficacy, the Building Team invited t the USACE staff in the Corps’ Fort Worth, Texas, office come to the Virtual Theater at HKS to view the model and witness the high-speed computing firshand; instead, the Corps staff chose to view the presentation remotely. At the end of that session, recalls Burk, the Corps’ in-house Revit expert acknowledged that “this design is much further along than anyone has suggested.” The Virtual Theater can take some credit for that.
THE NEXT JUMP IN TECHNOLOGY
There has been a quantum leap in computing technology in just the three years since Balfour Beatty and HKS worked together on the modernization of Walter Reed Army Medical Center, in Washington, D.C. On that project, recalls Burk, nobody even had a laptop powerful enough to store the Revit model. Thanks to the new generation of multi-core processor laptops with large-capacity hard drives and better network capabilities, anyone can plug a laptop in at the Virtual Theater to view the full 3D model. Balfour Beatty has a similar room called the CAVE (Computer-Aided Visualization Environment) at its Fairfax, Va., headquarters.
“Years ago, when we would travel to some location where a contractor would have a similar pseudo-room on the job site, we’d ask ourselves, Why not do something like that right here in our office?” said Barrick, the HKS principal. “Now, looking at how often the Virtual Theater is booked, it’s become apparent that we’re going to need more than one.” BD+C
