| Long-span spatial reticulated structure (LSRS) is one of the commonly used structural systems. Due to its flexibility, LSRS is very sensitive to dynamic actions caused by both winds and seismic loads. Therefore, it is necessary to find out an economic, efficient and reliable method to reduce the structural wind-induced vibration. Because of its complexity, it is difficult to set up the mechnical model of LSRS. Fuzzy control technique which is an intellectual control strategy and the combination of fuzzy logic and control technique, can be used to reduce the wind-induced vibration of LSRS primely without creating a precise structure model.The simulation of wind-load time series, which is based on Autoregressive (AR) model of linear filtering method, is introduced. The simplified fuzzy controller for LSRS is constructed, and the interpolation polling list is constituted by using Mamdani inference method. The numerical simulation and its comparison for vibration control for the typical spatial reticulated structure with the simplified fuzzy controller are carried out.Futhermore, the self-adjustment fuzzy controller for LSRS is made out, the analytical form of control rule with one or more adjustment factors is illuminated, the step response of fuzzy control system with different adjustment factors is compared, and the self-optimization of control rule with four adjustment factors is operated. By using this fuzzy controller, the numerical simulation for vibration control of the typical long-span spatial reticulated structure is made. The comparison for the dynamic responses between self-adjustment fuzzy controller and usual fuzzy controller as well as the comparison between before and after the adjustment factors'self-optimization are carried out.Besides, an improved genetic algorithm is put forward to study the quantity and placement optimization of fuzzy controllers, and the algorithm results in faster search and higher computational precision by adjusting high effective coding and control distribution of the initial population. In addition, the sufficiency function which can synchronously implement the quantity and placement optimization is constructed. And the quantity optimization and placement optimization of fuzzy controller for wind-induced vibration reduction of LSRS is investigated.Also, the stability analysis for fuzzy control system is introduced and the stability analysis of linguistic fuzzy control system is studied deeply. |
