Removal of the Arch Span of the Old Sava Bridge, Belgrade

Podizanje lučne konstrukcije Starog savskog mosta, Beograd

The dismantling of the Old Sava Bridge in Belgrade is perhaps our most complex international project to date, with one of its most critical stages being the removal of the steel arch structure.

The work had begun long before we arrived on site. The lifting structures mounted on the two TS barges used for the operation, each 52 metres in length, had been out of service for years, so the first task was to bring them back into working order. In Hungary, at the Danube Heavy Cargo Handling facility, we inspected and serviced the systems, then continued the preparations in Mohács, where final fine-tuning and trial operation took place. The steel structures were assembled using rope access techniques, while the hydraulic and electronic systems were recalibrated and the control system reconfigured. Minor faults occurred during the initial trial runs, but once these had been corrected, the lifting equipment began to operate with increasing precision. The onboard winches were also overhauled and reprogrammed to ensure that all systems would work together reliably in Belgrade.

Once all our equipment was technically ready for the task, the specially outfitted lifting barges 1509B and 1510B set off, pushed by the tug Zsombor, and arrived in Belgrade within a few days.

During the operation, the arch structure, weighing approximately 420 tonnes, was lifted hydraulically, step by step. The towers of the lifting equipment worked in 30-centimetre increments, with constant attention paid to ensuring that the structure rose evenly at every point. This was not a task about speed or spectacle, but about keeping every movement fully under control.

The removal was ultimately completed successfully: the arch was lowered onto the barges, where it remained until the shore-side pull-out track had been completed. Only then could the structure be hauled onto land in a multi-day operation carried out in carefully planned phases.

The task was technically highly complex, consisting of many small, interdependent stages: preparation, testing, fine-tuning, and finally the actual lifting operation. Together, these made it possible to safely remove a structure of this scale from its position while working on water in a densely built urban environment.

Rušenje Starog savskog mosta u Beogradu je možda naš najsloženiji međunarodni projekat do sada, a jedan od najvažnijih koraka je bilo podizanje čelične lučne konstrukcije. Radovi su već počeli mnogo pre nego što smo stigli na lokaciju.

Mehanizmi za podizanje koji su korišćeni za podizanje, izgrađeni na dve TS barže, svaka dužine 52 metra, nisu bili u funkciji godinama, pa su prvo morali biti „vraćeni u život“. Po povratku u Mađarsku, na lokaciji Dunai Nehézrakodó, pregledali smo i održavali sisteme, a zatim nastavili pripreme u Mohaču: tu su se odvijala fina podešavanja i probni rad. Montaža čeličnih konstrukcija je izvršena korišćenjem alpske tehnologije, dok su hidraulični i elektronski sistemi ponovo kalibrisani, a sistem upravljanja ponovo podešen. Na početku probnog rada bilo je manjih grešaka, ali nakon što su one ispravljene, mehanizam za podizanje je radio sve preciznije. Takođe smo renovirali i reprogramirali vitla na brodu kako bismo osigurali da svi sistemi mogu da rade zajedno u Beogradu. Kada je sva naša oprema bila tehnički spremna za zadatak, specijalne barže za dizanje 1509B i 1510B krenule su sa potisnim brodom Žombor i stigle u Beograd u roku od nekoliko dana.

Tokom operacije, lučna konstrukcija od približno 420 tona podizana je korak po korak pomoću hidrauličnog dizanja. Kule mehanizama za dizanje radile su u koracima od 30 centimetara, stalno vodeći računa da se konstrukcija ravnomerno podiže u svim tačkama. Ovaj posao nije se odnosio na spektakularnu brzinu, već na držanje svih pokreta pod kontrolom.

Podizanje je konačno prošlo glatko, luk je postavljen na barže i ostao je tamo dok nije završena staza za izvlačenje na obali. Struktura je mogla biti odvučena do kopna u višednevnoj, faznoj operaciji. Zadatak je bio tehnički složen, sastojao se od mnogih malih, međusobno povezanih koraka: priprema, testiranje, fino podešavanje, a zatim i samo dizanje. Zajedno, ovo je omogućilo bezbedno podizanje tako velike konstrukcije sa njenog mesta, radeći na vodi u gusto izgrađenom gradskom okruženju.