07/10/2026
Marina Bay Sands Hotel and Sands SkyPark, Singapore
Design Architect: Safdie Architects
Executive Architect: Aedas
Structural Engineer: Arup
Opened in 2010, Marina Bay Sands is defined by three hotel towers whose geometry creates an unusual structural problem before the SkyPark is even considered. [1][3] Each tower has a nearly vertical west side and a curved, inclined east side, creating the large continuous atrium between the two halves. Unlike a conventional high-rise where wind normally governs lateral stability, Arup found that the primary lateral demand in Towers 1 and 2 is generated by gravity itself. The eccentric self-weight of the curved eastern walls produces permanent overturning forces in the short direction that can exceed those from wind. [4] Reinforced-concrete shear walls between guestrooms and the elevator cores provide the principal lateral system, while link trusses at Level 23 couple the two sides of each tower and limit differential displacement across the upper floors. [4] Because structural self-weight directly increases this gravity-induced overturning, the floor system was designed as lightweight post-tensioned concrete slabs spanning up to approximately 10 m without internal columns. [4] The geometry also produces long-term sideways movement from self-weight, creep and shrinkage, so precamber, staged analysis and predictions of movements extending decades into the building's life were incorporated into the design. [4]
Approximately 200 m above ground, the Sands SkyPark changes the structural language from concrete high-rise construction to bridge engineering. The structure is approximately 340 m long and 38 m wide, with more than 7,000 t of structural steel and a 66.5 m cantilever extending beyond Tower 3. [2][4] Above Towers 1 and 2, the SkyPark consists of steel framing supporting composite slabs, while the bridge sections spanning more than 50 m between towers use three longitudinal steel trusses with transverse girders at approximately 4 m centres. [4] The three towers do not move identically, so the SkyPark cannot behave as one rigid beam. It is divided into five joined plates and three principal tower zones, using movement joints, fixed bearings and guided bearings to accommodate differential movement caused by gravity, wind and seismic effects. [1][4] The 66.5 m cantilever presented a different problem again. Arup selected two post-tensioned variable-depth steel box girders, generally about 3.55 m deep and increasing to about 10 m near the Tower 3 support. [4] Oasys GSA was used for global structural analysis, while Strand7 finite-element dynamic analysis investigated vibration from wind and human activity. Large tuned mass dampers were installed within the SkyPark and verified through full-scale vibration testing. [2][4]
The complexity continues below ground. Marina Bay Sands was constructed on reclaimed land containing deep soft marine clay, requiring major excavation and foundation engineering. [2] Circular and peanut-shaped diaphragm-wall cofferdams were used to reduce temporary strutting and maintain access across the exceptionally congested site. For the Hotel Peanut cofferdam, earth pressures derived from OASYS FREW were transferred into a three-dimensional SAP2000 finite-element model to study stresses, deformation and load transfer through the diaphragm walls, cross walls and fin walls. [5] Bachy Soletanche records 305 barrette piles extending to about 78 m, 164 bored piles extending to about 66 m, diaphragm walls 1.2 to 1.5 m thick and approximately 17,000 m³ of jet-grouted ground within its Marina Bay Sands works. [7] Construction of the highly inclined hotel walls also required temporary steel struts, vertical post-tensioning and continuous monitoring of stresses and movements, with back-analysis performed when measured behaviour differed from predictions. [4] BIM connected these different scales of engineering, from tower analysis to steel fabrication, with structural model data transferred into Tekla for downstream detailing and fabrication. [6][8] Marina Bay Sands is therefore not one structural idea but a sequence of interacting systems: gravity-driven concrete towers, bridge-like SkyPark structures, movement joints, dynamic control, deep geotechnical works and construction-stage engineering coordinated through a shared digital workflow.
References in comment.
