The tower’s structural system is a cast-in-place, high-strength, reinforced-concrete column superstructure. The shape and size of the columns were determined through the use of wind-tunnel testing and three-dimensional computer modeling to analyze building stresses. The building core is a cylindrical concrete form that acts as the central pillar for the tower. As the building ascends, the rotation at each floor occurs around this central mass. The building was constructed using a “jump form” system that takes advantage of its repetitive nature.