Research On Mechianical Properties Of Segmented Sliding Friction Pendulun Isolation Bearings

Bridge structure design has undergone transformation from traditional aseismic structure design to structural oscillatory control technology.Bridge isolation technology uses energy dissipation devices to control structural displacement effectively and uses isolation devices to reduce the energy transfer of earthquake motion to the superstructure,which as an important research and application part of passive control technology.The sliding isolation bearing passes the seismic energy of the substructure to the superstructure through the friction force of the contact surface.The smaller friction coefficient ensures that the superstructure is not too strong,and seismic energy is consumed by friction.It has good seismic isolation and energy dissipation effect.The traditional sliding isolation bearing has the disadvantages of large sliding volume and no self-recovery after the earthquake.On the basis of the friction pendulum bearing,a rotary sliding fork mechanism is added to design a segmented sliding friction pendulum isolation bearing with self-recovery performance.The main contents and achievements of this paper are as follows:?1?The function,structure and working principle of the new bearing are briefly described,and the principle of isolation and energy dissipation is studied.The finite element numerical simulation software ABAQUS is used to analyze the nonlinear static contact analysis of the strength and stiffness of the new bearing and the main components.The influence of the mechanical properties of the new support structure by sliding plate material parameters under2 supporting modes.?2?The theoretical model of the square direction force displacement of a new type bearing and cyclic loading is established.The calculation expression of the horizontal recovery force under 2 stages is derived and the hysteresis curve of the support is drawn under 2 working conditions.The theoretical expression of the equivalent linearization parameters of 2 kinds of supports is analyzed and proposed.?3?The ABAQUS software is used to analyze the horizontal hysteresis characteristics of the new support.The influence of the gap d₀ of the support parameters and the friction coefficient on the equivalent damping ratio and energy consumption of the support are studied,and the accuracy of the theoretical mechanics model is analyzed and verified.Compared with the friction pendulum bearing,it is concluded that the new bearing has strong friction and energy dissipation performance.At the same time,the influence of the support parameters on the slip,energy consumption and the acceleration response of the superstructure under the harmonic displacement excitation is studied.The reference of parameters selection based on the dynamic performance design of the new support is proposed.?4?Based on the simple harmonic vibration analysis,the random response results of the new support under the action of 2 kinds of site seismic waves are further studied.At the same time,the influence of the structural parameters d₀ of different forks,the dynamic coefficient of the slip,the dynamic coefficient of the structure,the energy consumption is emphatically analyzed.The parameter design selection parameter of the new support under the action of the specific seismic wave is proposed.The dynamic response of 2 kinds of bearings under different earthquake excitation is compared and studied.Compared with the traditional friction pendulum support,the new support can more effectively control the slip and increase the friction energy.