R2 infrastructure project Slovakia

Longest bridge in Slovakia

A technically particularly demanding section of the R2 at a point 200 km east of Bratislava has been in place since March 2020. The 9 km long stretch also includes the longest bridge in Slovakia (5 km). It is being built using solid concrete and precast concrete elements for the support brackets, which are being produced by long-standing MC customers Strabag and Doprastav. To ensure optimum quality of the precast concrete elements, MC’s concrete technologists were called in to develop the mix design and provide concrete admixtures and concrete release agents. They recommended a combination of the high-performance superplasticiser MC-PowerFlow 3131, the hardening accelerator MC-FastKick 105 and the release agent Ortolan Premium 702.

MC’s concrete expertise for monolithic precast elements

MC-PowerFlow 3131 is based on the latest polycarboxylate ether technology from MC and promotes the early strength development of the concrete, which is particularly important in the production of precast elements. It can be economically metered and produces concretes with low tackiness. This also simplifies and accelerates installation. The hardening accelerator MC-FastKick 105 was also used, exerting a positive effect on the crystal growth of the calcium silicate hydrate phases in the concrete for significantly increased early strengths without any negative influence on the other concrete properties. With MC-FastKick 105, precast plants can achieve the strength required for demoulding much faster and thus increase their turnaround for more economical and efficient production. Last but not least, the concrete release agent Ortolan Premium 702 resulted in the achievement of first-class stripped concrete surfaces thanks to its refined high-performance process oils. In addition, large quantities of Emcekrete 60 A and F grouting concrete were likewise used for this project.

With the combination of these MC speciality products, it was possible to manufacture the precast elements required for the bridge on schedule and in the desired quality. Completion of the challenging section between Kriváň and Mýtna is planned for summer 2025. By then, the R2 will be the longest motorway in Slovakia with a total length of 337 km.