The Hungarian National Infrastructure Development Private Company Limited (Nemzeti Infrastruktúra Fejlesztő Zrt. – NIF) gave the assignment to design Győr’s eastern relief road and the new Mosoni-Duna river bridge. The Mosoni-Duna river bifurcates from the main stream of Duna between Dunakiliti and Dunacsúny. After circling around Szigetköz, the Mosoni-Duna river will conflate back with Duna. Then, the Mosoni-Duna crosses Győr, where the relief road demands a new aesthetic bridge above the river.
Our company came up with numerous design plans. Ultimately the client and the city chose our cable-stayed draft. The most important aspects were the unique look and the modern shape, which aligns with the city’s development plans.
The structure is a cable-stayed bridge with a single pylon and reinforced concrete substructure. The orientation of the pylon, the single cable plane above the riverbed, and the anchor cables’ forking give the bridge a unique look. The pylon has a 67-degree forward inclination, and the area of its cross-section is shrinking with height.
Length of the structure: 213,6 m
Spans: 144 m and 68 m
Height of the structure: 66,74m
Total weight: 3906 t
Width of the structure: 29,73 m
The capacity of the bridge is 2×2 lanes of roadway, two bicycle lanes and a pedestrian sidewalk. The steel technical drawings were made with Trimble’s Tekla Structures 2019i. From the first steps, 3D modeling gave us a powerful tool to present, shape, and share our bridge idea. Due to the complexity of the geometry, we encountered numerous obstacles during modeling. We aimed to find the optimal size for the construction segments. We were restricted by the fact that the segments could only be transported on roadways. The river proved to be too shallow to move parts. How we achieved the designed shape of the centerline required a lot of planning and consideration.
In the end, we decided to use an incremental launching method on temporary supports built on the riverbed. The temporary supports will provide the centerline shape, and optimal cable stress will be reached when the structure is lifted from the supports.
We analyzed the difference between a curved and an orthogonal model. The geometrical error at the joints was so negligible that it could be solved with different weld sizes. The hardest part of the modeling process was the pylon. The linearly changing cross-section is designed with “T” stiffeners. We had to solve the collision between the stiffeners and the cable anchoring plates while there were no parallel boundary plates. To achieve the slenderest shape possible, we analyzed contractibility. The model gave us a powerful tool to provide just enough space for the building technology of post-tension cables.
We assigned the workplane to the riverside boundary plates to create the pylon. In that 67-degree tilted plane, we modeled the joints between construction segments and riverside plates in an orthogonal system. These plates then served as base points for the complicated 3D modeling for the rest of the pylon. Due to the complexity of the bridge, there were numerous details left for modeling, such as cable anchoring for both the main span, the anchoring cables at the end of the girder, the joint connection and vicinity of the bearings, and the connection between the pylon and girder.
In conclusion, using 3D software proved to offer numerous advantages.
From the visualization, collision analysis, and parametric element marking to examining contractibility. Moreover, we expect our model to be useful for accurate fabrication. For numerous years our company has utilized Tekla Structures in infrastructural projects. However, the Mosoni-Duna bridge stands out for both its complexity and uniqueness. For this reason, we decided to enter the BIM Awards competition.
Client: National Infrastructure Development Private Company Limited (Nif Zrt.)
Designer company: UNITEF’83 Zrt.
Designers: Róbert Bartus Office Director
Ákos Kővári: Lead Engineer
Richárd Berta: Structural Engineer (3D modeling – girder)
András Halwax: Structural Engineer (3D modeling – pylon)
Tailerling János: Structural Engineer (superstructure and substructure analysis)
Gábor Szepessy: Structural Engineer (superstructure and seismic analysis)
Gábor Németh: Structural Engineer (superstructure and aerodynamic analysis)
Márta Székely: Structural Engineer (Detail designer)
Viktória Simon: DLA Architect (architectural design)
Domonkos Tóth: Architect (visualization)