Prestressed highway concrete bridge

Prague
A new 12.2km long section of the motorway is being constructed on the outskirts of Prague that will connect the D0 ring road (one of the most significant transport structures in the Czech Republic) with the D10 and D11 motorways, as well as many other major roads connecting the capital to its surrounding areas. A bridge was required at the second-most-important crossroads of this section of the ring road. Therefore, the expertise of Structural Engineer Jan Lamparsky of AFRY CZ was enlisted to ensure it would be delivered successfully.

About the project

The final bridge design has a single span of 43.5 m, with a width that varies from 78.3 m in the middle to 89.6 m at the ends. The supporting structure consists of 23 beams made of post-tensioned prestressed concrete.

The total area of the bridge is 3,800 m2.  It is covered in a one-meter thick layer of soil, for which various details of insulation, drainage of the insulation surface, and transition areas were required.

Whereas most bridge traffic is in a longitudinal direction, traffic on this bridge is at a 45° angle.

Engineering challenges

In addition to the difficulty of designing the rear walls and the frame connection to the supporting structure, the biggest challenge for Jan Lamparsky was the foundation of the bridge.

The first design he looked at was a frame bridge, but this would have been very economically inefficient and technically demanding to construct. It would have made it necessary to anchor it to the substructure, requiring connectors to bind reinforcement at the corners, as well as prestressing the retaining walls and frame corners.

I used IDEA StatiCa to evaluate various static system designs for the bridge. It showed me very quickly which proposals could be implemented, respectively, and which were the most advantageous, economically. Following successive calculations, I decided to design the structure as a semi-integrated single-span bridge on deck foundations.
Jan Lamparsky
Jan Lamparsky
Structural Engineer – AFRY CZ
Czech Republic

Despite the larger number of bearings required, this variant proved the best solution. The walls could be efficiently designed from reinforced concrete. By reducing the number of prestressing cables in the beams, it was possible to design a shallow foundation without the need to anchor it in the subsoil.

IDEA StatiCa saved me a lot of time and work. I used the possibility to convert the model from Midas Civil directly into IDEA StatiCa. The design and code-check of the reinforcement was then no longer a problem.
Jan Lamparsky
Jan Lamparsky
Structural Engineer – AFRY CZ
Czech Republic

Solutions and Results

With its atypical dimensions and shapes, the bridge structure has a single span of 43.5 meters of post-tensioned prestressed concrete. The construction is expected to be completed in 2026, at a total estimated cost of around €400 million.

Despite the various problems that arose during the design, working on this bridge taught me a lot. Thanks to help from my colleagues and the IDEA StatiCa help desk, we successfully came to a functional and economically advantageous final proposal.
Jan Lamparsky
Jan Lamparsky
Structural Engineer – AFRY CZ
Czech Republic

About AFRY CZ s.r.o

AFRY is an international engineering, design, and advisory company. The organization’s 17,000-strong team of experts provides innovative engineering and design services to its many clients (including large national investors, regions, and municipalities) across its divisions: Infrastructure, Industrial and Digital Solutions, Process Industries, Energy, and Management Consulting.

Originally operating out of Brno, Pilsen, and Prague, AFRY has grown through multiple successful mergers into the company it is today, able to offer a unique range of services, covering the areas of architecture, transport, industry, energy, buildings, and infrastructure.

With a focus on creating sustainable engineering and design solutions, the company has been awarded several significant domestic and international awards. Its emphasis on education and R&D has strengthened its relations with major universities and research centers.

AFRY won a 2021 IDEA StatiCa Excellence Award in the category of Infrastructure, Industrial & Recreational Structures for this D1 bridge proposal.

The firm won the category Infrastructure, industrial & recreational structures for this D1 highway concrete bridge in the IDEA StatiCa Excellence Awards 2021.

Learn what the engineer says about the project