A Comparative Study On Base Isolation Of Basement Roof Rubber Bearings And The Top Surface

To achieve the goal of earthquake isolation, the vibration isolation design of building structure is to have isolation device installed in certain parts of the structure. The rubber bearing base top surface isolation and the basement roof isolation both belongs to the category of seismic isolation design. The difference between the two kinds of isolation system is that the space position of the rubber isolation device. However, the isolation principle of two kinds of isolation system is the same. Both of them take effective adjustment to the natural vibration period of the superstructure by using isolation devices, so as to reduce the seismic energy transmitted to the upper structure, and achieve the purpose of isolating the earthquake.The dynamic response of the structure is derived from a combination of the simplified model and an in-depth understanding of the Lagrange equation. Based on the completion of the above preparation, the results are analyzed and summarized by MATLAB and ORIGIN software.By studying the response analysis of the five groups of seismic wave, a conclusion can be found that the basement roof isolation has a very good effect on isolation. When the equivalent stiffness kr = 2 000 k N/m, the isolation efficiency of the storey drift is more than 90%, even as high as 98.72%, except some special values; The isolation effect of the rubber isolation device is related to the equivalent stiffness and equivalent damping. The smaller the equivalent stiffness and equivalent damping ratio is, the better the isolation effect is. From the perspective of seismic isolation performance, the isolation efficiency of base top surface isolation and the basement roof isolation are particularly close. When the Cr=3 000 k N/(m·s) and Cr=5 000 k N/(m·s), the storey drift maximum value in the 4 ~ 5 interlayer of two kinds of seismic isolation bearings even equal, respectively, 1.40 mm and 2.10 mm.