The SeaTac Airport International Arrivals Facility is the most complex capital development project in the history of the 69-year-old Seattle airport. Located in one of the busiest airports in the Pacific Northwest, the project included constructing a three-story building, an elevated sterile corridor, and the world’s longest pedestrian walkway over an active airport taxi lane. One of the largest American-owned general contractors, Clark Construction, was responsible for the design and construction. While they have worked on 15 of the United States’ largest airports, this project caused them to face several challenges. The most complicated aspect of the project included remotely assembling a 3-million-pound, 320-foot-long center-span pedestrian bridge and then transporting it to the project location.
By leveraging BIM and reality modeling technology with Bentley’s SYNCHRO 4D, Clark Construction linked the model with the construction schedule, developing a digital twin to fully visualize the construction sequencing. The digital twin helped the team coordinate planning and was easily adaptable as plans changed during discussions. They used the application to simulate transport of the bridge across three miles through an active airport, enabling precise planning and execution. Despite the transport needing to occur in one night and in poor weather, the team safely delivered the bridge, successfully installing and fitting the iconic walkway within three-eighths of an inch—all while not causing airport disruptions. Moving forward, the digital twin will be used by the Port of Seattle for future facilities management purposes.