Looking to cut costs, waste and delays in infrastructure projects, governments are (finally) taking a cue from the private sector and adopting building information modeling (BIM). It's part of a larger growth trend: The global market for BIM is expected to grow about 22 percent by 2022, with the infrastructure construction sector breaking away as the fastest-growing user, according to Allied Market Research. While North America currently leads the use of BIM, the Asia Pacific region, with its burgeoning construction industry, will dominate the market by 2021.
By digitally representing all aspects of a structure, BIM allows team members to plan, design and document within a single, centralized system. England's £14.8 billion Crossrail project, one of Europe's largest engineering initiatives, is the first major public infrastructure project to rely heavily on BIM. “We built two railways: a physical railway and a virtual railway,” says Malcolm Taylor, head of technical information, Crossrail, London, England.
“We have a faster design process because we can quickly check the requirements, such as shape, size, color and function.”
—Malcolm Taylor, Crossrail, London, England
BIM allows the Crossrail project team and its contractors to work together in a controlled, consistent and coordinated way, Mr. Taylor says, as they burrow a 42-kilometer (26-mile) passenger rail line beneath greater London. With around 1 million computer-aided design files, Crossrail's centralized set of linked databases encompasses 25 design contracts, 30 advanced works contracts and 60 logistics and main works construction contracts. By making all project documents easily accessible, the BIM system speeds up execution. “We have a faster design process because we can quickly check the requirements, such as shape, size, color and function,” Mr. Taylor says. The system serves as “a single source of truth,” Mr. Taylor says, for all the project's documents, such as workflows, contracts and asset breakdowns.
And with all contractors required to use it, the system reduces risks by making design details and construction processes more visible, he says. It reduces errors by ensuring only the most up-to-date versions of models and documentation are used by all parties. Crossrail's thousands of project contractors and consultants use shared BIM data to check their work on-site against the digital models, thus reducing the discrepancies that can crop up among different contractors.
BIM's 4-D capacity—which not only details width, length and depth but also how Crossrail changes over time—lets the team assess progress against the schedule. Crossrail's first 4-D analysis cost about £125,000 to develop and execute, but it allowed the team to reduce one risk contingency by about £8 million, Mr. Taylor says. During the construction of the rail line's Farringdon station, the team discovered that a schedule disconnect between boring the tunnel and constructing the station could have delayed the point at which the team could take out the tunneling machine. “The use of a 4-D model enabled us to quickly figure out exactly when we could take the boring machine out of the station,” he says.
Setting up the BIM system was a one-time cost of about £2 million, but the team recouped that outlay and more by saving at least £5 million annually on software and IT support costs. Moreover, while U.K. construction projects typically see 5 to 12 percent of the budget spent on waste and design or procurement inaccuracies, the Crossrail team has lowered that figure to about 2 percent, Mr. Taylor says. The project is slated to be completed by 2018—on time and on budget.
Uncle Sam Benefits
U.S. government projects also have found that BIM leads to time and cost savings—a major concern for public projects that require U.S. congressional approval, says Charles Matta, deputy associate CIO, public buildings IT services, U.S. General Services Administration (GSA), Washington, D.C., USA.
The GSA's Public Buildings Service (PBS) constructs and renovates federal workspaces, such as courthouses, office buildings and land ports of entry, for the U.S. civilian federal government. The service was an early BIM adopter to help prevent budget overruns. “BIM helped us have better control and implement greater energy efficiency with our projects,” Mr. Matta says.
Each year, the PBS oversees up to 20 construction, repair or modernization projects. The average federal project cycle from initial planning through occupancy is about seven years long. “The biggest savings for us is in reducing time on a project,” Mr. Matta says. PBS found that BIM typically can shave off about 10 percent from a project's overall schedule, stemming from the increased coordination as well as the reduced inefficiencies, errors, change orders and delays. “The GSA experience with BIM has paved the way for greater adoption among public sector owners, domestically and internationally,” Mr. Matta says.
Still, project teams must devote resources to training their stakeholders in using BIM. The Crossrail team created an information academy where all of its contractors and designers—about 3,000 in all—went through a training session to learn how to work in the shared data environment. The PBS holds regular in-house seminars to train both internal and external stakeholders in BIM.
But when it comes to securing stakeholder buy-in, BIM's benefits make their own case. “Project managers see that the 4-D models enable everyone to get a better and quicker understanding of the project,” Mr. Taylor says. “They see that we're creating an environment where they can consume and use information very quickly. That saves time.” —Novid Parsi
