Scientific paper ID 2615 : 2024/3

There are different structural solutions of bridge facilities according to the method of implementation. They depend on the obstacles they have to overcome.

The developed report examines the different methods of building superstructures according to the method of implementation:

 monolithic construction,

 prefabricated monolithic construction,

 prefabricated construction,

 cantilever concreting,

 per-cycle push-out.

The publication also examines one of the most technologically innovative bridges built in Bulgaria in recent years- the bridge over the Struma river at km 366 215 along the Struma highway in the section of LOT 3.1 – Zheleznica TUNNEL. This bridge is also known as the bridge at the Zheleznitsa tunnel. It must overcome the following six obstacles: existing main road I-1 (E-79), existing electrified railway track. Blagoevgrad-Kulata line, prospective second track of the railway. Blagoevgrad-Kulata line, future design location of the existing fourth-class road BGL 1071, temporary road under a project serving the construction of the tunnel.

The choice of the ” per-cycle push-out” construction system is suitable because of the speed of construction, high quality, good operational indicators and economic expediency.