19.03: Amager bakke: Design challenges for a steel building with a recreational roof

Abstract

ABSTRACTIn every way, Amager Bakke is a spectacular construction. The 43,000 m2 combined waste to energy plant and artificial ski slope has a full height of 85 m. In its final form, the roof will provide public access for a park with the size of 2½ soccer fields. The park includes hiking, climbing, skiing area, viewing platform, and a café.The building has a high complexity due to several reasons. The exterior architectural expressions require the correct shape for a double curved skiing slope. This is merged with the interior demands for waste to energy machinery. The result was a complex geometrical structure for which steel was the only feasible material to apply when forming the superstructure. Furthermore, the fire compartmentation of the energy plant and the park gave special design issues concerning structural robustness and municipality's approval of the regulatory fire safety strategy. Finally, the roof needed to be prepared to carry natural trees.Early in the engineering process it was decided that an innovative approach was required. Therefore, the limits of BIM tools were challenged and widened. The 3D‐model has produced more than 3,000 drawings, and all structures are designed in the model. The model was also used for design layout, collision check, quantity surveyor, and for performing a building sequence illustration the erection timeline. Additionally, the model was continuously operated for interchanges with the client, the architect, and the contractor.The steel superstructure was executed in S235, S355, and S460 steel. A total of approximately 7,500 tons of weight was applied to the building parts. Various forms of large span roof steel girders were used with different static systems, to carry ∼1,000 concrete slab elements on the roof. The facade is covered with ∼1,000 aluminum bricks on steel sandwich panels and the cantilevered chimney hangs on the gable side starting more than 50 m above ground level and reaching 124 m above ground level. This construction required a tuned mass damper in the top, which gave rise to an interesting calibration to the actual natural frequency. The building complex also includes an 11‐storey office building, which caused additional demands regarding acoustical vibrational damping through the structures. It was solved by an innovative damped floor construction.