Tall building developments have been rapidly increasing worldwide. This paper reviews the evolution of tall building's structural systems and the technological driving force behind tall building developments. For the primary structural systems, a new classification -interior structures and exterior structures -is presented. While most representative structural systems for tall buildings are discussed, the emphasis in this review paper is on current trends such as outrigger systems and diagrid structures. Auxiliary damping systems controlling building motion are also discussed. Further, contemporary "out-of-the-box" architectural design trends, such as aerodynamic and twisted forms, which directly or indirectly affect the structural performance of tall buildings, are reviewed. Finally, the future of structural developments in tall buildings is envisioned briefly.

The tall building is the most dominating symbol of the cities and a human-made marvel that defies gravity by reaching to the clouds. It embodies unrelenting human aspirations to build even higher. It conjures a number of valid questions in our minds. The foremost and fundamental question that is often asked: Why tall buildings? This review paper seeks to answer the question by laying out arguments against and for tall buildings. Then, it provides a brief account of the historic and recent developments of tall buildings including their status during the current economic recession. The paper argues that as cities continue to expand horizontally, to safeguard against their reaching an eventual breaking point, the tall building as a building type is a possible solution by way of conquering vertical space through agglomeration and densification. Case studies of some recently built tall buildings are discussed to illustrate the nature of tall building development in their respective cities. The paper attempts to dispel any discernment about tall buildings as mere pieces of art and architecture by emphasizing their truly speculative, technological, sustainable, and evolving nature. It concludes by projecting a vision of tall buildings and their integration into the cities of the 21st century

New developments of tall buildings of ever-growing heights have been continuously taking place worldwide. Consequently, many innovations in structural systems have emerged. This paper presents a retrospective survey of the main structural systems for tall buildings with emphasis on the advancements of recent, emerging, and potentially emerging systems. A structural systems chart that was previously developed by the authors has been updated in this paper to recognize, categorize and add the more recent structural systems. Recent trends of tubular structural systems in modified forms including the braced megatubes and diagrids are presented. Core-outrigger structural systems are discussed with emphasis on their adaptability. The potential of employing superframes for stand-alone and conjoined megatall buildings is predicted. As a means to solve today's various project-specific complex design requirements, different mixed structural systems for supertall and megatall buildings are presented. This paper also discusses the widespread application of composite structural systems and recent trends of concrete cores for contemporary tall buildings. Finally, the future of tall buildings is predicted as the race for height continues.

There is much architectural and engineering literature which discusses the virtues of exterior bracing and diagrid systems in regards to sustainability -two systems which generally reduce building materials, enhance structural performance, and decrease overall construction cost. By surveying past, present as well as possible future towers, this paper examines another attribute of these structural systems -the blend of structural functionality and aesthetics. Given the external nature of these structural systems, diagrids and exterior bracings can visually communicate the inherent structural logic of a building while also serving as a medium for artistic effect. Viewed in this light, the visual appeal of these systems can be enhanced to give a tower a more distinct urban identity. This entails the creation of structural elements that are aesthetically pleasing, geometrically coherent and that demonstrate dexterity of application in regards to a building's composition, while also respecting the laws of physics and mechanics. In this fashion, an artistic approach can exhibit structural systems as not just purely rational features that enable the construction of tall buildings, but as important visual components that afford opportunities for creative expression. This paper, therefore, synthesizes the concepts of structural performance and creative artistry to facilitate a better understanding of the aesthetic developments in skyscrapers worldwide.

Considering the ubiquity of concrete's structural, architectural, and environmental applications in buildings, a research study was carried out to determine how the thermal mass property of concrete could improve the energy performance of buildings. The results have shown that extreme climate zones can better exploit the thermal mass property of the material. This article initially reviews the fundamental concepts of thermal mass. It then specifically explores the impact of thermal mass concrete on building energy performance in six U.S. climate zones through Energy Plus simulation and analysis. The building occupancy types (office and residential), window-to-wall area ratio, and height are chosen as the parameters to evaluate the impact of thermal mass on building energy performance. In addition, the annual heating and cooling energy demands are selected as the measurement indices of building energy consumption. This article presents the results of the study, interprets them, and draws conclusions about the potential benefits of thermal mass for both residential and office occupancies, which are deemed to be important to researchers and design professionals. These results indicate that other influential design variables such as slab thickness and thermal mass distribution could also be taken into account to demonstrate broader implications and benefits of thermal mass in different climate zones.