Phage 4
A) Passive Systems
Passive damping systems can be divided further into two sub-categories:
- Energy-dissipating-material-based damping systems such as viscous dampers and viscous-elastic dampers
- Auxiliary mass systems to generate counteracting inertia forces such as Tuned Mass Dampers (TMD) and Tuned Liquid Dampers (TLD).
B) Active Systems
An active structural control system is the one that has the ability to determine the present state of the structure, decide on a set of actions that will change this state to a more desirable one, and carry out these actions in a controlled manner and in a short period time. While some passive systems, such as
TMDs or TSDs, are effective only for a narrow range of loading conditions, active systems can perform effectively over a much wider range and they are a more advanced form of functional performance-driven technologies in architecture. Examples are active mass dampers (AMD) and active variable stiffness devices (AVSD). The AMDs resemble the TMDs in appearance, although the vibration of a building is picked up by a sensor, the optimum vibration control power calculated by a computer, and the movement of the building is reduced by shifting a moveable mass with an actuator. The AVSDs continuously alter the building’s stiffness to keep the frequency of the building away from that of external forces, such as earthquakes, to avoid a resonance condition. Although their cost-intensiveness and reliability issues are limiting the use of active systems at present, with more research, they would have great potential for future applications.
CONCLUSION
Among various types of structures for tall buildings, Diagrid is the one which has many advantages such as: aesthetic, structural performance, material saving potential, freedom of space arrangement thanks to the lack of structural columns, etc. Diagrid is becoming the predominant choice for
high-rise projects. Keeping in mind these features, this paper summarises the strategies to mitigate lateral forces which are suitable for high-rise Diagrid buildings, but also applicable to other types of structures. The strategies range from architectural design techniques such as modifying building
form, to structural reinforcement tactics, and using damping systems/devices.
REFERENCES
[1] H. E. Ilgin and M. H. Gunel, “The Role of Aeroynamic Modifications in the Form of Tall Buildings against Wind Excitation”, METU JFA 2007/2 (24:2), pp. 17-25.
[2] A. Kareem, T. Kijewski and Y. Tamura, “Mitigation of Motions of Tall
Buildings with Specific Examples of Recent Applications”, Wind and Structures, Vol. 2, No. 3, 1999, pp. 201-251.
[3] A. G. Davenport, “The Response of Six Building Shapes to Turbulent Wind”, Seria A, Mathematical and Physical Sciences. Vol. 269, No. 1199, A Discussion on Architectural Aerodynamics, 1971, pp. 385-394.
[4] P. Irwin, J. Kilpatrick, J. Robinson and A. Frisque, “Wind and Tall Buildings: Negatives and Positives”, The Structural Design of Tall and Special Buildings, Vol. 17, (2008), pp. 915-928.
[5] M. M. Ali and K. S. Moon, “Structural Developments in Tall Buildings: Current Trends and Future Prospects”, Architectural Science Review, Vol. 50.3, 2007, pp. 205-223.
[6] R. J. Smith and M. R. Willford, “The Damped Outrigger Concept ofr Tall Building”, The Structural Design of Tall and Special Buildings, Vol. 16, 2007, pp. 501-517.
[7] J. J. Connor, “Introduction to Structural Motion Control”, New York: Prentice Hall, 2003.
A) Passive Systems
Passive damping systems can be divided further into two sub-categories:
- Energy-dissipating-material-based damping systems such as viscous dampers and viscous-elastic dampers
- Auxiliary mass systems to generate counteracting inertia forces such as Tuned Mass Dampers (TMD) and Tuned Liquid Dampers (TLD).
B) Active Systems
An active structural control system is the one that has the ability to determine the present state of the structure, decide on a set of actions that will change this state to a more desirable one, and carry out these actions in a controlled manner and in a short period time. While some passive systems, such as
TMDs or TSDs, are effective only for a narrow range of loading conditions, active systems can perform effectively over a much wider range and they are a more advanced form of functional performance-driven technologies in architecture. Examples are active mass dampers (AMD) and active variable stiffness devices (AVSD). The AMDs resemble the TMDs in appearance, although the vibration of a building is picked up by a sensor, the optimum vibration control power calculated by a computer, and the movement of the building is reduced by shifting a moveable mass with an actuator. The AVSDs continuously alter the building’s stiffness to keep the frequency of the building away from that of external forces, such as earthquakes, to avoid a resonance condition. Although their cost-intensiveness and reliability issues are limiting the use of active systems at present, with more research, they would have great potential for future applications.
CONCLUSION
Among various types of structures for tall buildings, Diagrid is the one which has many advantages such as: aesthetic, structural performance, material saving potential, freedom of space arrangement thanks to the lack of structural columns, etc. Diagrid is becoming the predominant choice for
high-rise projects. Keeping in mind these features, this paper summarises the strategies to mitigate lateral forces which are suitable for high-rise Diagrid buildings, but also applicable to other types of structures. The strategies range from architectural design techniques such as modifying building
form, to structural reinforcement tactics, and using damping systems/devices.
REFERENCES
[1] H. E. Ilgin and M. H. Gunel, “The Role of Aeroynamic Modifications in the Form of Tall Buildings against Wind Excitation”, METU JFA 2007/2 (24:2), pp. 17-25.
[2] A. Kareem, T. Kijewski and Y. Tamura, “Mitigation of Motions of Tall
Buildings with Specific Examples of Recent Applications”, Wind and Structures, Vol. 2, No. 3, 1999, pp. 201-251.
[3] A. G. Davenport, “The Response of Six Building Shapes to Turbulent Wind”, Seria A, Mathematical and Physical Sciences. Vol. 269, No. 1199, A Discussion on Architectural Aerodynamics, 1971, pp. 385-394.
[4] P. Irwin, J. Kilpatrick, J. Robinson and A. Frisque, “Wind and Tall Buildings: Negatives and Positives”, The Structural Design of Tall and Special Buildings, Vol. 17, (2008), pp. 915-928.
[5] M. M. Ali and K. S. Moon, “Structural Developments in Tall Buildings: Current Trends and Future Prospects”, Architectural Science Review, Vol. 50.3, 2007, pp. 205-223.
[6] R. J. Smith and M. R. Willford, “The Damped Outrigger Concept ofr Tall Building”, The Structural Design of Tall and Special Buildings, Vol. 16, 2007, pp. 501-517.
[7] J. J. Connor, “Introduction to Structural Motion Control”, New York: Prentice Hall, 2003.
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