Seismic Control For Serially Connected Isolated Structures Subject To Two-directional Horizontal Earthquake

After 5.12 Wenchuan earthquake, the research and the application of seismic isolation technology has drawn much more attention than before. The structure that the rubber isolation pad is connected with the cantilever column is often used at home and abroad. The isolation structure has large space in isolation layer, and this is the major characteristic of the isolation structure. It also exists adverse effect which because of the cantilever column shaft and serially connected isolated system p -Δeffects producing to the isolator capacity and replacement performance simultaneously. If under the two-directional horizontal earthquake, this kind of adverse effect will be more prominent.In this paper, serially connected isolated structures are carried out a series of studies in the view of two-directional horizontal earthquake. With the efforts of author's research team, the seismic controller is placed to the isolation layer of isolated structures, then a new vibration control system of isolated structure is formed. According to the seismic control system of serially connected isolated structures, the motion equation is established with the two-directional horizontal earthquake; Sequential Optimal Control algorithm is used to control the example of serially connected isolated structures with five-story; the calculation model has been analysed for the time history analysis, and the contents of the following areas were discussed:First of all, the aseismic performance is studied in this paper, it shows that the serially connected isolated structures have a certain of damping effect. And to a certain extent, it can reduce the seismic response of structures.Second, according to the the cantilever column of the serially connected isolated structure in isolation layer, the parameter analysis has been analysis. In the column section with a certain size, by changing the height of the cantilever column in isolation layer, it can be obtain that the frequency of the serially connected isolated structures will be decreased with increasing the height of the cantilever column; in the column with a certain height, by changing the section size of the cantilever column, the frequency of the serially connected isolated structure will be increased with increasing the section seizeof the cantilever column.Third, according to the issues of seismic control to the serially connected isolated structures, combining with the Sequential Optimal Control algorithm proposed by the studying team, the algorithm can control the earthquake response of the serially connected isolated structures under two-directional horizontal earthquake. Through the analysis of the seismic response for a five-storey reinforced concrete frame teaching building, it shows that the system can effectively control the earthquake response of the teaching building under two-directional horizontal earthquake, and it can improve the stability of isolated structures, and also can ensure the security of structure. Based on the above studies, through the stability analyses of the control algorithm, it indicated that this control algorithm is stable. And the convergent speed in response of phase plane locus is most rapid, this shows the stability of improved algorithm is better.Finally, the serially connected isolated structure model test is introduced. And it discussed some of the major conclusions associated with this article.