Analysis Of Mechanical Properties Of Sliding Bearings Of Long-span Structures

The severe damage due to strong earthquake indicate that the active seismic codes is inadequate in the present structure design. The seismic isolation technique is suggested. Although some research results have been obtained in seismic isolation aspects recently. It is difficult to apply the technique to the practice engineering because there exist some faults. Among much seismic isolation technique, sliding seismic isolation technique can play isolation effect on which little research is carried out. At first, the course of development of various types of bearings is reviewed. Then, a kind of sliding bearing of long-span structure and its working principle is investigated. In this thesis, the mechanical properties of the sliding bearing were studied by using finite element software ABAQUS. The structure of the sliding bearing is optimized in order to provide a theoretical basis for its practical application in engineering. The main research work and results are in the following.(1) The compressive property of the sliding bearing is analyzed by using finite element method. By analyzing the compressive property in different thickness of the sliding bearing plate which is made of PTFE material, the differences of the maximum stress in the PTFE plates under the same loading are compared. Thus, the reasonable thickness of plates can be obtained.(2) The anti-pulling property of the sliding bearing is analyzed by using finite element method. By analyzing the axial tension and the eccentric tension under certain loading, the relative mechanical parameters are achieved to show if the sliding bearing arrives at the requirements of strength.(3) The hysteretic behavior of the sliding bearing is analyzed in different excitation conditions. The differences of the hysteretic behavior under different excitation are compared so that the mechanical properties of the sliding bearing are evaluated. By analyzing the displacement response of the sliding bearing under earthquake excitation, the reasonable net space between the out-shell and the core axis is determined.