Paper Session 3 :

Tall Buildings - Materials, Structure and Efficiency

Since the industrial revolution the rate of urban migration is constantly rising, and more people are relocating to the urban centers. Since 1950s the global urban population has increased from 751 million to a high of 4.2 billion (United Nations, 2018). A study on global populations trends by United Nations predicts that by year 2050, 68% of global population will be living in urban areas.

The urbanization of the cities in the middle east and south east Asia is happening at an alarming rate and these cities are becoming a hub for construction activities. As more inhabitants are concentrated in the urban centers, these cities are growing in their scale and energy demand. By year 2030 the number of cities with more than 10 million inhabitants will rise to 43 (United Nations, 2018). This clearly indicated the need for more cities and expansion of existing urban centers. As these megacities expand to accommodate the increasing population the demand for efficient

transportation and energy as well as infrastructure cost associated with that increases exponentially. Designing high density urban areas with mixed use buildings proves to be an ideal solution and building vertical as opposed to horizontal makes more sense.

Early 2000 saw a dramatic increase in the number of tall buildings being built around the globe. These buildings account for a significant amount of resources from construction to daily operations. The technological advancement in design of structural systems and construction techniques has made it possible to build super tall buildings. In 2018, the total number of tall building above 650ft was 1478 which is a 141% increase from 614 buildings in 2010 (CTBUH 2018).

Tall buildings are becoming one the most common building type in the contemporary urban environment. Tall building design is a complex process requiring collaborative efforts from multiple disciplines. Structural engineering is one of the important aspects of tall building design. Tall buildings are subjected to different types of forces throughout their lifespan. Gravity loads and Wind Loads are the two primary types of forces every tall building is designed for. To sustain

these forces the design of structural system of a tall building is extremely important. Efficiency of every structural system greatly depends on the type of system as well as the choice of the structural material (Khan,1974). The structural material not only impacts the strength performance but significantly affects the way these systems are constructed. Current research efforts are being made to study and optimize the structural systems and explore better and efficient construction methods. Studies related to newer structural materials in the tall building industry are rare and there is a lack of information on how these new materials can be utilized.

This panel discusses the ideas related to use of new materials in tall buildings design. What are the potentials of structural timber in construction industry? What other alternative materials can we utilize in the structural systems for tall buildings? How ca new improve performance of structural steel and reinforced concrete? Structural behavior is also addressed in this panel. What are the various methods and techniques to analyze the structural behavior of tall buildings? How can we develop new structural systems that are more efficient in terms of energy use and  more sustainable? We seek answers to similar questions to better understand the built environment in our metropolis in crisis.

Text by : Piyush Khairnar