Freeform Supertall Buildings

Abstract

To date, no research has been carried out in the literature that gives insight into the relationships between freeform and key design parameters in supertall towers (≥ 300 meters). This critical subject is investigated in this paper with data collected from 39 building cases, taking into account building function, load-bearing system, and structural material as design parameters. The key findings of the paper highlighted the following: (1) the only core typology was central core type; (2) mixed-use and office were the most favored functions; (3) the most favored system in freeform supertall tower projects was outriggered frame system; (4) composite construction was common among supertall towers and its closest follower was reinforced concrete; (5) building functions other than hotel exceeded 500 m in free form; (6) in the sample group, freeform buildings with outriggered frame and tubular systems exceeded half a kilometer as well; (7) both composite and reinforced concrete freeform towers pushed the limits of height considerably; and (8) as the number of some supertall tower buildings (such as hotel buildings) was not adequate, it did not seem possible to derive a scientific interrelation between the height of the building and the corresponding planning parameter. It is thought that revealing the current state of the free forms, which are among the most preferred skyscraper forms today, will shed light on the supertall building designs to be made in the future.