Research For Vibration Control Of High-rise Steel Structure Using Shape Memory Alloys

With the height of high-rise steel structures increasing, the response of the structures under seismic action increase remarkably, therefore, the study about vibration control of high-rise steel structures is very necessary. At the present time, it is an active demand to find an economic, practical, effective and no-energy required control measure, and to establish the corresponding theory and method. As a kind of new smart material, Shape Memory Alloys (SMA) have specific properties of shape memory, super elasticity, and have been paid much attention in the field of structural vibration control.In this dissertation, the vibration control using the smart SMA material on seismic responses of high-rise steel structure is performed to build a kind of vibration control system and to improve the seismic performance of the structure, which presents important significance in theory and substantial value in engineering. The key developments and creative achievements are contained in this dissertation as follows:(1) In accordance with the loading-unloading test on properties of SMA, a steady hysteretic-curve of stress-strain is gained, by which the material parameters are made certain. Then the test results and theoretical values are compared to confirm the constitutive relation model used in this paper is viable.(2) According to the theory of vibration control and the property of high-rise steel structure, the projects which use the SMA cables to decrease the structure response are put forward. The vibration control equation and method of numerical analysis are built based on the finite element theory and the super elasticity of SMA material.. (3) The 20-story steel structure is a benchmark model , which is built to provide a clear basis to evaluate the efficiency of various structural control strategies, by which the effectivity and adaptability of the SMA cables on the vibration control for high-rise steel structure is proved. An engineering example of high-rise steel structure using the SMA cables is built by ansys and then the time-history analysis for the seismic responses of the example is completed. With this example, the effect of the passive control system using SMA cables and its influencing factors on the vibration control of high-rise steel structure are studied to give a theoretical basis for the engineering application.