At the end of August 2021, the installation of the steel structure of the Prapratno viaduct, 212 meters long and weighing approximately 600 tons, was completed. Viaduct segments were transported from the Brodosplit pier to the port of Prapratno by ferry and were transported from the pier to the installation site by self-propelled modular transporters (SPMT) with a large capacity. The largest segment is almost 50 meters long and weighs 126 tons. Brodosplit made and painted the construction from 5 segments in its workshops, transported them to the construction site, and joined the segments together by welding. After that, they were pushed with hydraulic cylinders and a high-value threaded rod from east to west into the final position. This work was carried out on the construction site by 30 professional workers and engineers.
At the end of March 2022, the last segment of the Ston bridge was lifted and assembled, which was lifted by two mega cranes simultaneously in pairs due to the configuration of the terrain. The bridge is a total of 485 meters long and 40 meters high, and above the Gulf of Ston connects two tunnels Polakovica and Supava and has five pillars and two abutments. The entire range consists of six segments that were built in large 'Brodosplit' conditioned halls and were transported by barge by sea, which means that the quality and durability of such construction are significantly higher than when made from several smaller segments. The largest segment of the Ston bridge is 93.8 meters long (like a football field) and weighs 323.30 tons, and the assembly was carried out with the help of a Manitowoc mega crane with a capacity of 750 tons, which is the largest load that a Croatian company has handled independently.
- We are pioneers in this part of Europe, perhaps even at the world level, in that we do constructions of 400 tons in a closed space under controlled conditions - which we then place in one piece in the project. With one of our cranes, we can place up to 750 tons, and in a pair with two cranes like here, even up to thousand tons, pointed out Tomislav Debeljak, President of the Brodosplit Management Board.
Brodosplit did its part regarding the steel segments of the Ston bridge back in the fourth month of 2021, and according to the original dynamic plan, it was supposed to start with assembly, but due to Avax's delay in the work on the lower structure, the transport and assembly were moved to the beginning of August, so when it was seen that Avax doesn't arrive even then, installation is postponed to October.
In the summer months, the installation is simpler, the weather conditions are more acceptable, the days are longer and ensure two-shift work, and then the installation would be faster, and ultimately cheaper for Brodosplit. It was precisely the delay in the preparation of the lower structure that moved the planning deadlines on several occasions and prolonged the arrival of the segments for assembly from the screed. In less than a month and a half, Brodosplit ensured the high-quality implementation of this demanding project and assembled all segments of the bridge, and symbolically bridged the Ston Canal.
With the project of the bridge 'Ston' and the viaduct 'Prapratno', Brodosplit continues its positioning in the market niche of large metal structures. With these works, it strengthens the position of a prominent European shipyard that, in addition to building ships with high added value, is capable of building extremely complex and demanding steel structures. The construction, transportation, and assembly of metal structures are unique projects for Shipbuilding Industry Split, which constantly invests in equipment and machinery to meet the client's requirements in terms of quality, possibilities, competitive offers, and delivery deadlines.