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In the design of structure seismic response active control system, the paper employs five active control algorithms, such as classical linear quadratic optimal control, linear quadratic Gaussian optimal control, pole assignment control, independent modal space control and sliding mode control, to carry out theoretical analysis and numerical simulation of the linear structure model and provide the basis of semi-active control design.Based on active variable stiffness method, a new active variable stiffness frequency control algorithm for seismic response control is presented in the paper. The time-frequency information of nonlinear and nonstationary earthquake signal processing is identified based on Hilbert-Huang Transform algorithm.

Using active variable stiffness device, the stiffness of structures is changed to reduce the response to seismic excitation when the instantaneous frequency is close to the frequency of structures. In order to verify the feasibility and effectiveness of the algorithm, two steel-framed Benchmark models are presented. The effectiveness of the algorithm are thus proved through simulation analysis, and the displacement of the structure is reduced effectively. So it has a promising future in the engineering practice.Based on empirical model decomposition and Hilbert-Huang transform theory, the paper develops a new semi-active variable stiffness tuned mass damper(SAVS-TMD) frequency control algorithm for tall building wind induced vibration control. The new SAVS-TMD system has the distinct advantage as it continuously retunes its frequency due to real time control and is robust to changes in building stiffness and damping. The benchmark building under the discussion is a 76-story 306 meters concrete office tower in Melbourne, Australia. It is shown that the SAVS-TMD can reduce the structure response substantially, when compared with the uncontrolled case, and it can reduce the structure response further when compared with the case of TMD.

Additionally, it is shown that SAVS-TMD reduces response even when the building stiffness changes by±15% and it remains robust. It is demonstrated that SAVS-TMD can reduce the response as well as active tuned mass damper (ATMD) at the expense of much less power consumption.By employing the auto-regressive method and weighted amplitude wave superposition improved by using FFT method respectively, the stochastic fluctuating wind field and cross-spectral density function have been simulated by using the Davenport wind speed power spectrums and considering spatial correlation, stationary multivariate stochastic process.

The accuracy and the efficiency of the technique have been demonstrated by comparing simulating the wind speed spectrums with the Davenport target spectrums. A76-story 306 meters RC structure of the Second Generation Benchmark Vibration Control for Building is under the research. The numerical results of the dynamic response of the structure under TMD control and LQG control methods are given.Iterative learning control is a more satisfactory control strategy because of its own intelligence, which is able to improve itself constantly in controlling process. So it is gradually becoming an issue of concern. Based on the idea to combine the linear quadratic optimal control and iterative learning control, the paper proposes a new hybrid control strategy which is named linear quadratic iterative learning control to reduce the ea本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。