result of social protests against other alternative solutions. A large span bridge thus became necessary to allow for the unconstrained future modernization of Rę dzin water stage of fall and two water locks.The bridge consists of three substructures ( Fig. 2): -E1 southern fl yover: 610-m long, 11 span continuous beam (box girders) made of prestressed concrete, span lengths 40 + 2 × 52 + 56 + 6 × 60 + 50 m; -M2 cable-stayed main bridge: 612-m long, span lengths 50 + 2 × 256 + 50 m, with two separate superstructures made of prestressed concrete, suspended to a single 122-m high pylon;-E3 northern fl yover: 520-m long, nine span continuous beam (box girders), made of prestressed concrete, span lengths 50 + 7 × 60 + 50 m.The superstructure of the main bridge, presented in Fig. 3, consists of two box girders made of prestressed concrete class C50/60 (one for each carriageway of the motorway), suspended to an H-shaped concrete pylon (concrete class C50/60). Inclined side walls of the girders were made of reinforced concrete precast panels. AbstractThis paper describes the largest structure along the motorway ring road of Wrocław (Poland)-a cable-stayed bridge over the Odra River near Rę dzin barrage. The river flows there in its main bed, while inland navigation uses additional water channels. Pylon of the new bridge is situated on an island located between the river and the channels. The structure is 1742 m long and consists of two multi-span flyovers and a 612-m-long cable-stayed bridge with separate decks suspended to one 122-m-high pylon. The superstructure consists of two prestressed concrete box girders, one for each carriageway of the highway. The decks of the main bridge are suspended to a reinforced concrete pylon by 80 pairs of stay cables. The bridge with a deck area of approximately 65 000 m 2 was constructed within 36 months.

The road infrastructure in Poland has been intensively developed and modernised over the last years. During the past decade more than 2500 new bridges have been built along the main roads and motorways, including several large multi-span structures with a length of more than 500 m. This paper describes the design and construction of the cable-stayed bridge in Wrocław and the extradosed bridge in Kwidzyn. Both structures are the largest concrete bridges built in Poland and are also among world leaders in their class. They can presently be considered to be the greatest achievements of Polish civil engineering. The Rędziński Bridge over the Odra River in Wrocław is a 612 m long cable-stayed bridge with two spans of 256 m suspended to a single 122 m high concrete pylon. The bridge in Kwidzyn is a 808 m long six-span extradosed bridge with two longest spans of 204 m. The paper concludes with a brief comparison of both structures including consumption of materials and costs.

The road and railway infrastructure in Poland has been intensively developed and modernized for the last years. Around 300 new bridges are built annually. Among the new structures, there is a group of modern extradosed bridges. This paper presents examples of short-, medium-, and long-span extradosed bridges designed and built in recent years in Poland. The following structures are described in details: (1) the first Polish extradosed bridge; (2) two-span landmark viaduct over motorway; (3) multispan curved motorway bridge; (4) the longest Polish extradosed bridge; (5) tramway extradosed bridge; and (6) conceptual designs. The paper is concluded with geometrical parameters characterizing presented structures. The parameters are compared with values obtained for cable-stayed bridges and extradosed bridges built worldwide.

<p>The largest bridge along the motorway ring road of Wroclaw is a cable-stayed structure over the Odra River near Redzin water stage of fall. The river flows there in its main bed, while inland navigation uses additional water channels. An island, where the pylon of the new bridge is situated, is located between the river and the channels. The bridge is 1742 m long and consists of a 610 m long southern flyover, a 612 m long cable-stayed main bridge with separate decks suspended to one 122 m high pylon and a 520 m long northern flyover. The superstructure of the main bridge consists of two box girders made of prestressed concrete, one for each carriageway of the highway. The height of the girder is 2.50 m, which is about 1/100th of the main span length. The decks are supported by 80 pairs of stay cables connected to the pylon made of reinforced concrete. The bridge with a deck area of approximately 65 000 m2 was constructed within 36 months.</p>

<p>Highway ring road of Wrocław is a very important part of an urban communication network which is now under modernization work. It will connect the existing A4 highway with the S8 expressway being under construction. The ring road is 26.765 km long. Forty bridge structures were designed along or over it. Total length of highway bridges and viaducts is more than 6 km, that is equivalent to 22% of the whole route.</p> <p>The longest bridge is a concrete cable-stayed structure over the Odra River. The river flows in its main bed, while inland navigation uses additional channel with two locks. There is an island located between the river and the channel. The planned bridge is 1742 m long and consists of: south flyover 610 m long with continuous eleven span prestressed concrete box structure; main bridge 612 m long with two separate decks connected to a single concrete H-shaped pylon; north flyover 520 m long with continuous girders made of prestressed concrete.</p>