Steel Teams Lead The Way Toward 3-D Integration
There's Team Puma in the Great Plains, e-Steel in the Southwest, the Steel Frame Alliance in the Midwest and South, and a half-dozen others scattered throughout the U.S.
These so-called “steel teams”—structural engineers, steel detailers, fabricators, and erectors—are redefining the steel-construction process by using the latest 3-D modeling technology and standards in interoperability to minimize errors, speed fabrication and erection, reduce material waste, and cut overall project costs. These teams are winning more steel contracts because they're able to bring projects on line faster, within budget, and virtually error-free.
“When we interview for a project, we interview as a team—engineer, fabricator, erector, and suppliers, so it's the total package,” says Jack Petersen, PE, principal of the structural group with Martin/Martin Consulting Engineers, Lakewood, Colo., a member of Team Puma. Petersen says the team has won more than 20 bids based on the close collaboration of its members and the use of 3-D modeling.
“We create 3-D models that allow us to integrate all of the players' needs,” says Petersen. “In other words, we work within the limits of the suppliers we have in terms of material; we design the frame such that it is to the erector's liking; and we work to make the details of fabrication such that it can be automated.”
Here's how the collaboration process works: first, the steel team members standardize their many pieces of software on a single platform for interoperability, such as CIMSteel Integration Standards/Version 2. CIS/2 translates a program's native format into a neutral file format that allows data interchange across multiple software programs, including structural engineering analysis and design programs, steel detailing software, and fabrication systems. So software programs that were once incompatible can now talk to each other, exchanging data seamlessly.
This type of interoperability enables the steel team to reduce the time required to convert the structural engineer's design to fabricated components. Shop drawings can be reviewed and approved as they're being developed, which reduces lead times by eliminating the lengthy “revise and resubmit” process. Finally, because the drawings are more complete, structural engineers can be assured that their design will be properly executed at the fabrication level.
Once they're all on the same page, the team can then utilize the power of BIM and 3-D modeling software to front-load more of the design and construction planning work. Structural engineers work closely with the steel detailers, fabricators, and erectors to share and exchange 3-D model information to create much more detailed designs that have tighter tolerances. This enables mill orders to be placed earlier and steel to be delivered and erected on site much more quickly, with few field changes required.
This integrated design approach has helped save time and money on a number of high-profile projects. For instance, the Building Team for GM's $300 million V6 engine plant in Flint, Mich., was able to cut more than a quarter off the 85-week design and construction schedule by using BIM. Much of the schedule gain stems from the steel work. By front-loading the design and construction planning, the steel mill order was placed eight weeks earlier than typically would be possible and steel erection began eight days early, according to Lawrence F. Kruth, P.E., engineering and safety manager for Douglas Steel Fabricating Corp., Lansing. The team modeled the steel, mechanical, electrical, and plumbing designs in BIM, which eliminated conflicts of these systems during construction.
Similarly, the Building Team for the addition to the Denver Art Museum, which opened in October, completed steel erection two months ahead of schedule and saved $400,000 by sharing a 3-D model among the architect, structural engineer, steel connection designer, and steel delivery team.
While most early 3-D modeling and BIM success stories involve highly complex and costly projects, Petersen insists that these models work well for bread-and-butter work as well.
“We've designed more than 20 projects that you would consider average, run-of-the-mill work, like one- and two-story medical office buildings and school additions,” says Petersen. He says Team Puma regularly delivers the steel package ready for erection far before the foundation work is completed. “There's a definite improvement in schedule,” says Petersen. In terms of cost, he says there's no guarantee that the project will come in below budget, “but we can say that we'll hold the price quoted on day one.”
Such an extreme change to the construction process does have its challenges. For one, the way in which traditional contracts are written is obsolete. Contracts must now be written to mitigate risk and compensate steel team and other Building Team members for additional services rendered, says Larry Flynn, industry marketing manager with the American Institute of Steel Construction, Chicago. He says steel teams and project managers are developing special partnership agreements and design-build contracts that enable steel teams to share the risk.
As for the additional fees, Flynn says owners, general contractors, and construction managers are finding that the overall savings to the project far outweighs the additional fees charged for these services.