Belgrade Tower

Belgrade Tower (Serbian: Кула Београд, romanized: Kula Beograd), officially known as Kula Belgrade, is a 42-floor, 168-meter (551 ft) tall skyscraper as part of the Belgrade Waterfront project in Belgrade, Serbia. It was topped out in 2021 and ceremonially opened in 2024 but still lacks a use permit due to issues with the HVAC and fire protection systems. Its lower and upper floor plans are rotated by approximately 90 degrees relative to each other, with the geometric transition occurring between levels 12 and 20 through inclined and branching columns and post-tensioned transfer beams and slabs. The tower is supported by a piled-raft foundation necessitated by the mechanical properties of the upper soil layers; the piling works, performed by Novkol under the supervision of Mace, included 1,200 mm (47 in)-diameter piles beneath the tower and an extensive testing programme that included Osterberg-cell, static, dynamic and pile-integrity tests. The approximately 4,750 m3 (168,000 cu ft) concrete raft beneath the tower was poured continuously over about 60 hours in August 2019, after which the central core was raised using hydraulically operated jump-formwork, while post-tensioning was used for most hotel and residential floor slabs. Skidmore, Owings & Merrill developed the architectural concept and initial foundation and structural scheme, while AECOM prepared the second-stage structural design. A local joint venture comprising Energoprojekt Urbanizam i Arhitektura, Energoprojekt Entel and DNEC adapted and checked the design for Serbian approval requirements. The main construction works were carried out by a joint venture of Impresa Pizzarotti and Millennium Team, with DNEC acting as the engineer under the FIDIC contract and BG&E providing structural value-engineering consultancy during construction. Upon topping out in 2021, it remained the tallest building in the Balkans outside of Turkey by roof height for two years before being surpassed by the 202-meter (663 ft) Sky Fort...