This 44 storey helicoidal structure created real structural engineering design challenges, including the outward “bursting” forces created by the geometry which were redistributed by the use of post-tensioned ring beams at each level. A huge basement was formed using a secant piling procedure and dewatering which lasted several months prior to building. The principal frame was designed as a tube, with the outer reinforced concrete double helix structure taking both vertical load and up to 75% of the lateral wind bracing loads. The floors were designed as a mixture of composite steel and reinforced concrete. The Moucharabieh which acts as a sunscreenwas designed as four overlaid panels of complementary geometric patterns.
Prize for “The 50 Most Influential Tall Buildings of the Last 50 Years » awarded by CTBUH.