Backing into BIM
Although BIM has its benefits, the technology did not come to Coreslab overnight. After several of the Ontario, Canada-based producer’s North American operations had already begun the process, the Indianapolis plant started implementing BIM in 2008, when several major customers began requiring it.
“We were cautious to a degree,” says Greika. “We wanted to help design teams evaluate precast early on, but we’ve been down the path before of investing in a certain software only to find out that our customers didn’t want to use it.” Plant management chose Autodesk’s Revit software, which many of its architecture and engineering clients use.
Greika had the benefit of consulting with Coreslab colleagues in larger operations that were further along in implementing BIM. However, he cautions, “each precast plant has to evaluate its risks and determine what makes sense. You can’t just adopt what another operation is doing, even if they’re successful.”
In its initial investment, Coreslab’s Indianapolis managers decided against a full BIM implementation. The plant uses BIM in its design phase, establishing connections and penetrations and identifying potential problem areas in a 3D model. After that, they generate shop tickets in 2D.
With several major BIM projects completed and construction activity picking up, Greika says it makes sense to carry it through the entire process, from designing to generating tickets. “The further we can take the 3D modeling, the fewer chances of introducing human error, and the more accurate we’ll be,” he says.
Although contractors and specifiers have been the most proactive in adopting BIM, Mortenson sees more precasters coming onboard. “A few years back, we were selling our suppliers on BIM,” says Frank. “Now most of the big general contractors are requiring it and we see it more as a qualifier, similar to a safety rating. If a producer doesn’t use BIM, it doesn’t qualify for the bid.”
Laying the groundwork
The precast industry is actually ahead of many others with adopting BIM in the U.S.
“Precast has set the templates and procedures that will help other products, such as masonry, adopt it more easily,” says Mark Perniconi, executive director of the Charles Pankow Foundation. “I give the Precast/Prestressed Concrete Institute (PCI) credit for being pioneers in this effort.”
Since 2006, the foundation and PCI have funded the development of the Precast Concrete National BIM Standard (NBIMS). The Precast NBIMS group has worked to identify the scope of BIM for precast, its design requirements, and practical ways to implement it.
Much of its work has been focused on overcoming precasters’ biggest hurdle to implementation: software compatibility. The interoperability of data is key to the success of BIM for any industry, and major BIM software companies—including Nemetschek, Tekla, StructureWorks, Bentley Architecture, and Autodesk—are providing input. The goal is to allow universal communication between various BIM software programs in a neutral data exchange; the most common is called Industry Foundation Classes (IFC).
The precast standard is part of a National BIM Standard for the U.S. (NBIMS-US) being developed by the BuildingSmart Alliance, a council of the National Institute of Building Sciences. NBIMS-US is an evolving, consensus-based set of technical and practice specifications that could eventually be adopted by the construction industry.
This effort has been slow to catch on, as it attempts to encompass such a vast range of products and processes, and lacks the government support required for enforcement. Industry stakeholders seem to agree that a national standard will not be what convinces precasters to adopt BIM. “The real driver will be customer demand for BIM-driven projects,” says Roger Becker, managing director of research and development for PCI.
PCI supplements the NBIMS-US effort by supporting work on BIM data exchanges. “Over the past year, we have learned that the National BIM Standards world was not ready for a domain as large as precast concrete,” says Becker. “Mechanisms for validation of data exchanges were rudimentary, manual, and terribly time-consuming.”
This disconnect has prompted a new phase of work for PCI, funded by the Charles Pankow Foundation. Professor Chuck Eastman, the “Father of BIM,” leads a project at the Georgia Tech Digital Building Laboratory to automate the data checking process within IFC, ensuring the correct information is where it should be for different software platforms to work together. Eastman also serves as a technical advisor to Precast NBIMS.
Within BIM for precast, PCI has identified 11 key points of data exchange in which different systems must communicate. These can be within a precaster’s operation (for example, tying estimating software to robotic stations) or between project partners (from a rebar supplier’s software to the producer’s). “Precast is complicated because producers can play the role of primary contractor, subcontractor, or manufacturer on various projects,” says Perniconi.
Eastman’s group has validated one of these 11 exchanges and plans to finish the remaining 10 by the end of this year. BIM software companies can begin testing and implementing the exchanges, even as they’re being developed and tested.