Denver International Airport Expansion

Anatomic Iron Steel Detailing
USA

This project is a new hotel and airport commuter train station for access to the airport by train from downtown Denver. The signature feature of this project are the two very large canopies, one free standing over the train platform and the other extending under the hotel itself and cantilevering out on both the north and south side of the hotel. The rolled steel arches over the hotel canopy carry the hotel. The canopy cantilever on the north side is a staggering 41 m (135'-0"), and on the south side 21 m (70'-4"). The anticipated deflection at the tip of the north cantilever is around 10-15 cm (4 to 6 inches). These canopies are constructed using diagrid technology, which like an eggshell transfer the load across the surface of the canopy down to the massive abutments. On the train canopy, each abutment consists of over 100 truckloads of concrete.

The hotel is shaped to roughly resemble an airplane, with a rolled steel roof. The architectural intent, when viewing the hotel and canopies together, is to create the sensation of flight or flying - an appropriate concept for the Denver International Airport. On this project Anatomic worked directly for the Engineer of Record (Miro), using Tekla In-Model Reviewer, and cooperated with the Architect (Gensler) using BIM.

The "leading edges" of these two massive canopies are fabricated from heavy Gr. A709 (fracture critical)  plate, made into box beams. As these box beams extend around the edges of the canopies, they twist and roll following a non-constant and non-parabolic ever changing radius. To achieve the required shape and roll of these plates, the team used Tekla component 19, with the workpoints only 2,5 cm (1") apart. They additionally added workpoints on the surfaces of the steel to give us workpoints that could be used to provide plotted roll paths on the shop drawings. The geometry of these leading edges was extremely complex, and the resulting data carried in the model was huge, requiring the team to use Dell super computers when processing the model.

Everybody used Tekla, including the EOR, the fabricator and erector. This made planning, data exchange and problem solving between the key players on the job much easier. Having the flexibility in Tekla to customize, the team was able to program special X-Y-Z tables on the shop drawings and e-plans, to show the workpoint path for the various rolled plates. Additionally, we were able to use Tekla Field Layout Points for the erector, to allow him to use Total Station to field survey key workpoints by use of a .txt file exported directly from the model, along with X-Y-Z tables on the erection diagrams. The team used many Custom Components, due to the complex CJP plate connections with internal stiffeners at the diagrid connections in hundreds of locations. Without Custom Components the connecting would have taken 10 times longer.