Study On Isolation Properties Of Sliding Artifact Isolation Bearing

China is a multi earthquake country,and each time the destruction of the earthquake on museum collection of movable cultural relics is very serious,the problem is highly valued by the relevant departments of the state,reducing the impact of the earthquake on the collection of cultural relics is very urgent.In this paper,finite element model of isolated and non-isolated museum is established,and the process of seismic waves transmitting to the two kinds of museums is studied.The floor wave is obtained and used as the load of the sliding artifact isolation bearing.Then a finite element model of the sliding artifact isolation bearing is established.the period of the structure can be controlled by the spring of isolation bearing,and the process of the floor wave transmitting to the showcase is studied.Based on the sliding artifact isolation bearing,a variable stiffness artifact isolation bearing is designed,and its design method and isolation effect are studied.The main research work and achievements are as follows:(1)Fisrt,a isolated museum and a non-isolated museum model is established in MIDAS.In accordance to the norms,two seismic waves and one artificial wave are selected,and their time history is analysised.The floor wave of different height is extracted,and their spectral characteristics are obtained by Fourier transform.The results show that the peak values of the floor wave acceleration of the museums(including isolated museum and non-isolated museum)increase with the number of floors,and the floor waves of different floors under the same earthquake have similar spectral characteristics.Isolated museums have a blocking effect on the earthquake,non-isolated museums have a amplification effect on the earthquake.(2)A showcase-bearing model is established in ABAQUS,which sliding artifact isolation bearing is used in.The load of the floor wave is obtained in Chapter 3.The stiffness of the bearing is adjusted,and the acceleration response spectrum and displacement response spectrum of the artifact are obtained.The analysis shows that the period of the structure can be controlled by changing the spring stiffness of sliding artifact isolation bearing.For the isolated museum,average acceleration peak of the floor wave can reach 0.52m/s2 under the rare earthquake.The average acceleration peak of the structure is controlled at 0.21m/s2 by sliding artifact isolation bearing and the isolation rate is 59%.The average displacement peak of the structure is 149mm.For the non-isolated museum,the average acceleration peak of the floor wave is 4.45 m/s2 under rare earthquakes.The average acceleration peak of the structure is controlled at 0.34m/s2 by sliding artifact isolation bearing and the isolation rate is 92%.The average displacement peak of the structure is 124mm.Sliding artifact isolation bearing is more suitable for non-isolated museum structures.In addition,combined with the front analysis,the sliding artifacts isolation bearing design method is proposed.(3)A showcase-bearing model is established in ABAQUS,which variable stiffness artifact isolation bearing is used in.The load of the floor wave is obtained in Chapter 3.The analysis shows variable stiffness artifact isolation bearing has good isolation effect on both the isolated museum and non-isolated museum,which's effect is more obvious on the non-isolated museum.Variable stiffness artifact isolation bearing can achieve different design goals under different seismic strength.It is more effective to control the acceleration response of cultural relics under the frequent earthquakes.On the other hand,it can control the displacement of cultural relics more effectively under the rare earthquake.In addition,combined with the front analysis,the variable stiffness artifact isolation bearing design method is proposed.