Study On The Control Algorithm Of The Intelligent Laminated Magnetorheological Elastomer Isolator

At present, base isolation has been a well-developed earthquake protective technology. Under several major earthquake, a large number of rubber isolation structures such as buildings and bridges have successfully withstood the trials. But under the near-fault pulse-like earthquake, the isolation layer would have a lot of internal forces and deformation, which brings negative impact on the seismic performance and design of base-isolation structures. In this case, we introduce a new kind of laminated bearing using magnetorheological elastomer (MRE) instead of ordinary rubber materials, in order to utilize its magnetorheological effect to make a smart adjustable isolation system. The result shows that the MRE-based intelligent isolation is a kind of excellent semi-active control device. The mechanical performance of MRE can be varied in real time by the application of additional magnetic field, so as to obtain satisfying isolation effect. Therefore, it is a promising way to use MRE-based intelligent isolation to resolve on structural vibration control in civil engineering.This paper mainly focus on the following areas:(1) The motion equations of isolation systems under earthquake are established, then an engineering example is simulated by the algorithm of Runge-Kutta in four step order method, when given synthetic near-fault pulse-like ground motions. The results of seismic response analysis show that under the near-fault ground motion, isolation layer will have larger internal force and displacement. Therefore, it is very necessary to use MRE-based smart isolation and search for a new structural vibration control method.(2) The mechanical model of the MRE-based bearing is established. According to the former research, the switch control strategy, i.e variable stiffness control mode is put forward, and the simulation with Matlab/Simulink is carried out. The final results show that switch control strategy is simple and practicable, and MRE-based isolation could mostly achieve the design requirement for shock absorption.(3) In order to get more favorable isolation effect, we should choose appropriate semi-active control algorithm. In this paper, minimal controller synthesis (MCS) algorithm is applied in the study of MRE-based intelligent isolation structural control and in the simulation of the example above with adaptive control algorithm. The results show that MCS adaptive control algorithm could approximate the seismic response of reference model and achieve the ideal control effect.