Study On Semi-active Mode Fuzzy Control Algorithm For Structural Vibration With Magnetorheological Damper

The semi-active fuzzy mode control algorithm with magnetorheological damper was suggested,to improve present algorithm and to limit the amount of fuzzy inference during control process.A numerical model was established,for the analysis of seismic mitigation efficiency of a 20-storey steel frame structure with magnetorheological damper.The fuzzy control rules were built for the control object of minimizing the total system mechanical energy during every sampling time interval.1)This algorithm could notably reduce the amount of determination of fuzzy relationships among the multiple states variables and the amount of inference for identification of fuzzy control rules during control process.2)Six representative recorded earthquake waves,including the EL-Centro wave,were input into the controlled structural model and the uncontrolled structural model to compute to compute their earthquake dynamic responses.It is shown that for the controlled ones,the time history of storey displacement and storey velocity will rapidly decrease with increment of time,and their amplitudes will decrease either,which means the good seismic mitigation efficiency for them.But it is also shown that storey accelerations will be enlarged.3)The maximum seismic mitigation efficiency of semi-active vibration control with magnetorheological damper for storey displacement and storey velocity could reach about 50%.When the maximum Coulomb force is within a reasonable range,eg.8000 k N<fdmax<20000k N,which means the resultant of all the forces from dampers installed in a storey unit,the seismic mitigation efficiency will exhibit positive correlation with the value of fdmax.4)Due to the difference between semi-active control and AMD(active mass damper)in principle,and the steady-state error between fuzzy control and precise control,the magnetorheological damper needs to output more force than the AMD actuator in order to achieve the same damping efficiency as AMD.On the other hand,since the semiactive device is with the advantage of simplicity and of consuming little amount of energy(for the servo-valve),the semi-control seems to be with more applicability.As is known,fuzzy control is also with simplicity and easy implementation,so it is believed that semi-active fuzzy mode control with magnetorheological damper is closer to practical application.Figure 48;Table 13;Reference 62...