Seismic Response Analysis And Experimental Study Of Isolation Structure Based On The New Type Roller Isolation Bearing

Due to the advantages of clear theory,mature technology and good shock absorption effect,isolation technology has been widely used in the construction and earthquake protection projects in various countries.The laminated steel plate rubber bearing is widely used in isolation technology,but it is not suitable for the isolation of houses in the rural areas where the technology is relatively weak.Therefore,it is urgent to develop a new generation isolation device with good effect,stable performance and economical isolation device to protect the lives and property safety of the people in the vast villages and towns.In this paper,the mechanical properties of a new type of steel roller bearing for the use of houses in villages and towns are studied.At the same time,this paper completes the seismic response analysis and experimental study of isolated structures.The main contents and results of the study are as follows:(1)According to the structure of the novel steel roller isolation bearing,the mechanical model of the support is obtained.For the experimental study,a group of steel roller bearings and friction pendulum bearings(FPB)are designed.Then the horizontal performance tests of these two groups of supports are completed.The results show that:The new steel roller isolation support can control the output load below a certain limit value,and its isolation effect is better than that of FPB.Based on the experimental results,the mechanical model of the new steel roller bearing is modified.(2)The aseismic model of six stories masonry structure is established by software ETABS to extract the quality and stiffness of the structure.Then,the seismic model and the roller isolation model are established by software Matlab.The seismic isolation layer of the roller isolation model is defined by the mechanical model of the novel steel roller vibration isolation.Two natural waves and one artificial wave are selected,and the peak acceleration of 0.07 g,g 0.20 g and 0.40 g are inputted into the seismic model and the roller isolation model,respectively,and the structural dynamic response analysis of the model is completed.The results show that:Compared with the seismic model,the rolling axis isolation model can reduce the acceleration response of the superstructure by 1 / 2~6 / 7,and the isolation effect is better with the increase of the earthquake intensity.However,the energy dissipation capacity of the roller isolation system is weak,and the isolation layer displacement exceeds the limit under rare earthquake.(3)In order to improve isolation effect of the roller isolation system and control displacement of the isolation layers,the viscous damper is added to the isolation layer of the pure roller isolation system in the 6 story masonry structure,which makes it a hybrid damping isolation system.The influence of the damping parameters on the hybrid isolation system is analyzed,and the hybrid damping isolation system with 3 or 6 viscous dampers is established respectively.The two kinds of isolated structures are modeled by Matlab software,and the seismic response is analyzed.Finally,the analysis results of seismic structure and pure roller isolated structure are compared.The results show that: The isolation effect of the hybrid damping isolation system is better than the pure roller isolation system.And both of them can reduce the acceleration response of the structure by 30%~80%,and the isolation effect is better with the increase of earthquake action intensity.(4)In order to verify the accuracy of the mechanical model of roller isolation bearing.And to verify the feasibility and effectiveness of hybrid damping isolation system.The aseismic model of two-story steel frame,the pure roller isolation model,the roller isolation model using passive-on and passive-off magnetorheological dampers and the friction pendulum isolation model are made.At the same time,3 seismic waves of 0.10 g and 0.20 g were input to each model respectively,and the shaking table test was carried out.The test results show that:The hysteresis curve of isolated layer of pure roller isolation system is consistent with the theoretical mechanical model proposed in this paper.The hybrid damping isolation system can reduce the acceleration response of the top layer of the structure by 83.2%~90.4%,and the pure roller isolation system can reduce 63.3%~75.5%.And friction pendulum isolation system can reduce 23.6%~57.0%.For hybrid damping isolation system,the optimal damping value increases with the increase of earthquake intensity.At the same time,the hybrid damping isolation system can reduce the isolation layer displacement by 47.7%~87.4% compared with the pure roller isolation system,and the control effect is better with the increase of damping.In addition,the acceleration and displacement response of the pure roller isolation system attenuate slowly,while the structural response of the mixed damping isolation system can attenuate rapidly.(5)The shaking table test model is established by using the software Matlab,and the time history analysis is carried out,then the simulation results are compared with the test data.The results show that:The simulation results are in good agreement with the experimental data.