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of the reinforced concrete walls, link beams, slabs, largest magnitude pile load test performed to date raft, piles, and the spire structural steel system. within the region. The piles utilized C60 cube strength Under lateral wind loading, the building deflections (8.7-ksi) SCC concrete, placed by the tremie method are well below commonly used criteria. The dynamic utilizing polymer slurry. The friction piles are analysis indicated the first mode is lateral sideways supported in the naturally cemented with a period of 11.3 seconds. The second mode is a calcisiltite/conglomeritic calcisiltite formations, perpendicular lateral sideways with a period of 10.2 developing an ultimate pile skin friction of 250 to 350 seconds. Torsion is the fifth mode with a period of kPa (5.2 to 7.3 ksf). 4.3 seconds. The Burj Dubai Tower pushes the limits on construction techniques and material technology, including self-climbing formwork system, prefabricated wall reinforcement, specially modified cranes, high-speed high-capacity construction hoists, and GPS monitoring systems. Tower foundations The tower foundations consist of a solid, 3.7-meter (12.1-foot) thick pile supported raft poured utilizing 12,500 cubic meters (m3) (16,350 cubic yards, yd3) of C50 cube strength (7.25-ksi) self-consolidating concrete (SCC). The raft was constructed in four separate pours (three wings and the center core). Each raft pour occurred during at least a 24-hour period. Reinforcement was typically spaced at 300 mm (12 inches) on center in the raft, and arranged such that every tenth bar in each direction was omitted, resulting in a series of “pour enhancement strips” throughout the raft; the intersections of these strips created 600-mm by 600-mm (24-inch by 24inch) openings at regular intervals, facilitating access and concrete placement. The tower raft is supported by 194 bored cast-in-place piles. The piles are 1.5 m (5 feet) in diameter and approximately 43 m (141 feet) long, with a capacity of 3,000 metric tonnes (3,300 tons) each. Each was pile load tested to 6,000 metric tonnes (6,600 tons). The diameter and length of the piles represent the largest and longest piles conventionally available in the region. Additionally, the 6,000-metric-tonne pile load test represented the Wind engineering For a building of this height and slenderness, wind forces and the resulting motions in the upper levels become dominant factors in the structural design. An extensive program of wind tunnel tests and other studies were undertaken by the wind tunnel con