A stand-out landmark

The Caracău is the largest concrete arch bridge in Romania. Completed in 1946, the railway viaduct underwent extensive renovation from 2018 to the end of 2019, with MC products not only used for the repair work but also for the protection and subsequent visual enhancement of the structure.
The Caracău Bridge connects the Romanian provinces of Transylvania and Moldavia and forms part of a very important railway line in the country. The bridge has a total length of 264 meters and its arch has an opening of about 100 meters. The maximum height from bridge to ground is 61 metres. The upper section of the structure was refurbished in 2006. And now the time had come to completely rehabilitate the rest of it – an undertaking that involved an extensive mix of measures. The project was sent out to tender by the Romanian railway company Căile Ferate Române (C.F.R.) in 2016, with the project being awarded to the specialist railway contractor Constructii Feroviare Mures SA in 2017. Due to the problematic conditions in this mountainous region, the work only began in May 2018 and then continued with interruptions through to November 2019.

 

Difficult environment

The constantly changing weather conditions and the limited accessibility of the construction site in the mountains became a logistical challenge for everyone involved. The maximum weight of materials that could be transported to and stored in the impassable area was four tonnes. Yet, by the end of the project, the total weight used amounted to over 100 tonnes. And those were not the only obstacles. All participants were confronted with difficulties in selecting the right materials in order to achieve the highest degree of functionality, safety, protection and aesthetic attractiveness. Each step of the way, MC area manager Codrut Belei was on hand with all his know-how to advise the planners, trades and subcontractors. 
Due to the location and construction of the bridge and the difficult weather conditions – which made the all-important curing of a mineral system virtually impossible – special MC mortars based on epoxy resin were used for the work.

Repair and refurbishment with MC systems

For the re-profiling of the concrete, the planners decided on a combination of the universal epoxy resin MC-DUR 1200 VK and special quartz sand, a mix that had already proved successful during the first partial refurbishment involving the upper bridge section. MC-Injekt 1264 TF, a special resin for rigid crack injection, was also used. The ECC fine filler Nafufill EC 6 was applied to the entire bridge – covering an area of around 15,000 m² – in a layer thickness of 3 mm. And the crowning finish was provided in the form of the surface protection coating MC-Color Flex pure in a light grey shade. The aim was to ensure that Caracău Bridge stood out as a bright landmark in the natural environment while also permanently protecting it from the weather. MC-Color Flex pure with its excellent technical properties and exceptional ease of application offered precisely the solution required.
In the end, MC products were applied to the entire bridge – including the railway line itself. MC Area Manager Codrut Belei commented with more than a little pride: “It was quite overwhelming – and for me it has been my biggest, most challenging and most rewarding project with MC so far.”