Sava River Bridge, Serbia

Sava River Bridge or the Ada Bridge is a single pylon cable-stayed bridge under construction over the river Sava at island Ada Ciganlija in Belgrade, Serbia.

The bridge is being constructed to reduce the traffic congestion occurring in Belgrade. It will become part of the inner city semi-ring road and be linked to the city highway.

It will divert traffic from the highway to the semi-ring road and vice versa. Economic studies have revealed that the existing roadway will face a severe traffic collapse by the end of 2021.

The bridge is expected to be opened to traffic in December 2011. The entire project will be completed by 2013.

Sara River Bridge project

The project involves construction of the bridge, the southern approaches and the northern approaches. The bridge will be a single pylon asymmetrically built structure.

The northern approach is being constructed under two lots. Lot one includes a 2km long, six-way dual carriageway from the intersection with Tosin Bunar Street to New Belgrade Railway Station. Lot two includes a 1km long, six-lane dual carriageway from New Belgrade Railway Station to the Juri Gagarin Interchange.

The southern approach will include Radnicka interchange, Hippodrome interchange, Pozeska Street, Pastroviceva Street and a connection between the Hippodrome and Radnicka Street Interchanges.

Bridge design features

The bridge is single pylon cable-stayed, the largest of its kind in Europe. It will be 929m long and 45m wide with six traffic lanes, two pedestrian or cycling pathways and a single rail line. It will be supported by 80 stay cables fixed to the needle like pylon situated at a height of 200m.

The bridge comprises seven spans. The main span is 376m long and is provided with two hydraulic lift-push equipments. It is counter balanced by a 200m long back span.

Side span forms the northern section of the bridge. The southern side of the bridge is connected to the approach roads through an end span.

The needle / cone shaped concrete pylon is founded 37m deep on a circular diaphragm wall. The radius of the pylon decreases from 16m at the base to 4m at a height of 175m and a 1.5m diameter at the apex.

The lower part of the pylon is split into two legs situated at a height of 98m from the base. The legs penetrate to the street lanes and light rail track. One of the legs is provided with an elevator whereas the other has a shaft provided with emergency stairs.

Construction of the Ada Bridge

The main span is being built without any temporary supports. The back span and pylon will be linked to each other through a pier table after construction has been completed. The side and main spans are being constructed simultaneously.

The construction work was initiated in April 2009. Steel fabrication was carried out in China in June 2009. Piling works were completed in July 2009.

The first fabricated superstructure steel segments were delivered on site in November 2009. The cable stayed bridge was installed in August 2010. The Hippodrome interchange, a 600m four-way dual carriageway, was opened to traffic in December 2010.

Pedestrian pathway of the bridge was opened to public in August 2011.

Contractors involved in the bridge development project

The Ogranak Sava Most consortium won the design and construction contract of the bridge in April 2008. The consortium includes PORR Technobau und Umwelt, SCT dd. and DSD Bruckenbau.

PORR is the coordinator and involved in the construction of all the piled foundation works, substructure, superstructure, pylon and installation of bridge cables.

DSD is supplying the structural steel required for the main span. SCT is supplying the reinforcing steel for pylon concrete and is also involved in the construction of the side span.

The preliminary design of the bridge was provided by Ponting Maribor in 2006 and the main foundation bridge was designed by LAP Stuttgart and DCF Vienna.

Seismic design and wind tunnel testing will be performed by EZI, concrete will be supplied by Beton Plus, formwork will be carried out by DOKA, earth works are being carried out by Vlado Baumaschinen, post-tensioning works will be carried out by BBV and labour works will be done by Bau Plus.

Financing the Sara River Bridge construction

The entire project including the construction of the bridge is estimated to cost £320m. It will be jointly financed by city of Belgrade, European investment Bank (EIB) and the European Bank for Reconstruction and Development (EBRD).