COVER STORY design information from engineering models to the BIM model. This also facilitated the transfer of information between Revit and Excel which BYME, the MEP contractor, was working with. The entire process significantly reduced the time taken to manage this information and ensured the accuracy of data that was being transferred (Figure 4 to Figure 6). Compact yet strong support structures Concrete nodes, also known as thrust blocks, sit atop the ring beam, deftly suppor ting the huge roof. The design and construction of these 20 thrust blocks was the highlight of design integration on the project (Figure 7). The competing demands of the architectural geometry, structural forces and construction methodology provided a huge challenge to the design team. Typically, the size of the concrete blocks suppor ting the large longspan roofs would have been of the order of two to three times the size of the space available in the Singapore Spor ts Hub. To overcome this problem, the design and construction teams worked collaboratively to incorporate all elements of the thrust blocks into the defined geometry, ensuring safety and quality of construction. This process involved extensive 3D modelling of the thrust block elements, as well as one-to-one drawings that facilitated the placement of reinforcement within the complex structural units (Figure 8). The thrust blocks are crucial nodes of intersections, that hide the complexity within but fully suppor t the magnificent roof by restraining the lateral thrusting forces exer ted by it. Though petite in size, they speak volumes for what an integrated design and construction team can produce with dedication and commitment (Figure 9).
Figure 5: Combined structural models for the National Stadium. Image by BYME.
Figure 6: Revit version of the roof combined with the bowl - the Revit version was used to carry out design integration of the MEP. Image by BYME.
Figure 7: Ring beam sections and actions
Figure 8: An isometric view of thrust block reinforcement
August 2016 THE SINGAPORE ENGINEER
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