19 grudzień 2025
The world’s first prefabricated double-track double tram turnout Read morePrefabricated turnout slabs for the UJ junction are ready
The Straszewskiego–Piłsudskiego street corridor in Kraków will be renovated using, among other things, the CONTRACK technology. Prefabrication of key components of the tram turnout system is intended to reduce inconvenience and shorten the standard installation time. The manufacturer has already completed production of the large-format prefabricated elements—they will be installed on-site like giant puzzle pieces.
CONTRACK technology will be used for the reconstruction of Straszewskiego Street from Smoleńsk Street to Piłsudskiego Street, and Piłsudskiego Street from Straszewskiego Street in Kraków (UJ/AST).
KZN Contrack is the manufacturer of prefabricated concrete turnout components—large-format slabs that will be used for installation. The company is part of the KZN Bieżanów Group.
The steel components of the turnouts are manufactured by Kolejowe Zakłady Nawierzchniowe “Bieżanów,” the parent company of the KZN Bieżanów Group.
The contractor responsible for the works and the recipient of the prefabricated elements is a consortium of SPAW-TOR Sp. z o.o. (leader) and PROGREG BUDOWNICTWO Sp. z o.o. (partner).
So far, CONTRACK technology has been used in cities such as Poznań, Bytom, Mysłowice, Ruda Śląska, and Warsaw (Plac Zawiszy – the entire turnout system, including 121 large-format CONTRACK slabs installed in 5 weeks). In Kraków, the technology has previously been applied during the renovation of the tram crossing on Telimeny Street. The UJ junction, however, marks the first such extensive use of the technology in the city—52 large-format prefabricated reinforced concrete CONTRACK turnout slabs with a total area of approx. 660 m² will be installed. Their production required around 237 m³ of concrete, and the largest slab weighs 21.8 tonnes. This will allow for the complete installation of a triangular track system consisting of three single double-track turnouts, 11 of which feature hybrid reinforcement.
The tramway prefabricated elements will be received and installed by the modernization contractor—SPAW-TOR.
Traditional installation of tram turnouts requires multiple layers of concrete to be poured directly on-site, each needing 28 days to cure. CONTRACK slabs undergo this process at the manufacturing facility and arrive on-site ready for installation.
Producing the track system in a tightly controlled factory environment—unaffected by external conditions—ensures far greater precision and initial product quality, resulting in increased durability of the structure. Combined with the highest installation standards, the result is a fully integrated turnout system designed for long-term service.
During installation, the technology saves time otherwise required for “wet” concrete works, but the real benefits emerge during operation. The durability of the concrete structure is three times greater than that of a steel turnout structure. CONTRACK allows for the steel components to be replaced without disturbing the concrete slab. Over the lifespan of the prefabricated elements, up to three turnouts can be installed without repeatedly removing and rebuilding the concrete structure.
Another important advantage of CONTRACK prefabrication is the standardization of installation technologies—both for straight track sections and turnout junctions. This enables the use of identical construction and maintenance processes over long distances, improving work organization, reducing construction duration, and minimizing problematic interfaces between different technologies—ultimately reducing costs.
Each CONTRACK slab is designed specifically for the particular turnout, crossing, or—as in the case of the UJ/AST junction—the entire turnout system. There are no ready-made, mass-produced solutions. To meet the highest standards, ensure optimal initial quality, and maximize the slab’s lifespan, CONTRACK employs double quality control.
The first stage takes place immediately after production, when the geometry of each slab is inspected individually. The second stage—observed at the CONTRACK assembly yard—is the test assembly: all slabs for a given stage (in this case, a batch of 13 slabs) are laid out and fitted together with the steel turnout components. This gives the manufacturer full certainty of precision and allows the contractor to carry out the works smoothly at the final installation site.
Applying CONTRACK technology to modernize the UJ/AST junction in Kraków—the very city where the technology was developed—is a step toward a modern approach to upgrading key infrastructure and a chance to reduce the social costs borne by residents. In strategically important locations for both tram and car traffic, such as the UJ junction, CONTRACK can deliver its best benefits: extending the lifespan of the track system, shortening future renovation times (thanks to the possibility of replacing only the steel portion), and—under favorable conditions—speeding up project delivery.
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