Document Type : Original Article

Authors

• Reza Akbari ¹
• Payam Gholbeigi ²

¹ Assistant Professor, Deputy Road Maintenance and Transportation Organization, Tehran, Iran

² PhD student, Sazeh Software Group, Isfahan, Iran

Abstract

In recent decades, significant efforts have been made to control the torsional displacement of structures, especially in high-rise buildings and irregular structures. In this research, the optimality criterion method has been employed and the eccentricity between the centers of mass and stiffness of structures has been minimized to reduce the torsional behavior and control the associated lateral displacements. This eccentricity mainly affects the dynamic response, the torsional behavior, and the final structural design. The efficiency and capability of the method has been shown by using three sample structures of different systems. The results have been presented by changing the eccentric moment values in subsequent steps in the optimization process. In the first sample, the torsional behavior of a multi-story frame simplified by a rigid floor system supported by linear springs has been improved. In the second sample, the torsional behavior of a four-story frame building with high level of plan irregularity, due to high eccentricity between the centers of mass and stiffness, has been improved. In the last sample, the response of a three-span concrete bridge with high irregularity due to different piers heights and stiffnesses has been assessed by optimizing the size of the bridge piers.

Keywords

• Optimality criteria
• replacement springs
• static condensation
• the center of mass
• the center of stiffness

Main Subjects

• Earthquake