RO | EN  
   


APECC Projects
Order by ...
project type | delivery date | project leader | list all projects
Rehabilitation of the Traian Bridge in Timisoara [ completed ]
Date of completion : 2005-05-07
Beneficiary : Cityhall of Timisoara
Project type : Technical project and execution details
Project leader : conf. dr. ing. Adrian Bota

The bridge, the execution of which was public auctioned in 1911, was built in medieval style, which had to fit in the neogothic architecture from the left bank of the Bega channel. The structure was finished in 1914, but, because of the war, the bridge was given in exploitation only starting with 1916, being considered an “ancient” bridge of the city. It is made as a Gerber beam of reinforced concrete, with spans (10 + 12,25) + 13 + (12,25 + 10) m and a total gauge of 17,00 m, being designed for the pedestrian traffic, auto and tram. The main span that assures the passing of the channel consists of the marginal superstructures cantilevers and an isostatic central span. The cross section reveals 9 girders of reinforced concrete with variable dimensions. The traffic develops on 4 lanes. The footways have technical channels and pedestrian parapet made out of wrought iron on the central span, respectively of shaped stone on the end spans.Due to the fact that the maintenance and rehabilitation works were not executed in time, a new expertise was necessary in 2000. The structural analyse realized on a spatial model, using live loadings from tram and truck convoys, showed that a consolidation of the central span and that of the marginal girders, is imperative.

The execution of all the necessary repairs was also requested. The bridge was included in the tramways rehabilitation program mentioned earlier. The most important detected damages are:

  •  the low bearing capacity due to the old design rules (90 years);
  •  not viable systems for fixing the tram rails on the superstructure;
  • degradations of the pedestrian forged iron parapet, as well as the stone parapet;
  • not viable and destroyed expansion joints and bearings;
  • degraded water-proofing on wide areas;
  • degraded short cantilevers, with improper supports and corroded reinforcement;
  • massive degradations of concrete and reinforcement of the footway cantilevers.
The possibility of consolidating the central span with carbon fibres was studied, although the chances this system to be a success were minimal because of the low concrete quality of the structure. Due to the fact that the colmatation of the cracks had a very high incertitude degree (numerous cracks, with different orientations and hidden by cement grout), we made the decision to abandon the consolidation solution of the central bridge deck.

The central bridge deck, out of reinforced concrete, was demolished through longitudinal fractionation. After the clearing of the emplacement followed the consolidation of the short cantilivers by executing horizontal drillings and reinforced bearing blocks out of C25/30 concrete. In the horizontal drillings high tensile alloy steel bars of 20 mm were introduced and tensioned at 120 kN. The bearing areas, which will become inaccesible after mounting the central bridge floor, were repaired and protected with a Sika multiple layer system . The initial bridge floor out of reinforced concrete, was replaced with a bridge floor realized in a mixed concrete-iron solution, which respected the initial structure geometry of 9 girders and 4 cross beams, provided with holes designed for the electrical cables and one water pipe.  The steel girders are HE 550A (S275) profiles and the cross beams in the field are HE 340A (S275), respectively the end cross beams HE 280B (S275) profiles. In contrast to the initial solution, the beneficiary, the Cityhall of Timisoara, asked for the enlargement of the footway, in order to be able to add a cycleway parallel with the pedestrian way. In order to grant the requestement, adequate steel cantilivers were designed which have to support the footway realized out of a reinforced concrete slab of 9 cm. The footway plate will be realized in two steps by using precasted concrete slabs of 4 cm and a monolyth concrete layer of 5 cm.
In order to realize the footway the initial solution will be kept. The protection of the pedestrians will be assured with a separating tube breastwork and the pedestrian parapet  will be reconditioned and mounted back on the bridge with an adequate, more complex fixation system on the concrete girder.