有初始转角的隔震支座在不同方向地震水平力作用下的力学性能研究
Research on Mechanical Properties of Rubber Bearings with Initial Rotation Under Horizontal Seismic Forces in Different Directions

为了研究大跨度空间结构支座转动问题，对上下表面发生相对转动的橡胶隔震支座水平力学性能进行了研究。运用有限元分析软件ABAQUS研究了支座无初始转角时的水平性能，分析了有初始转角橡胶隔震支座在？？X向、Y？？向和45°向水平位移加载下的支座水平力学性能，得出了水平刚度与剪应变之间的变化关系。结果表明：？？X？？向和45°向水平位移加载时，在小剪应变下，支座水平刚度随初始转角的增大而减小，之后随初始转角的增大而增大；？？Y？？向水平位移加载下，在大剪应变之前，水平刚度随初始转角的增大而减小，之后随初始转角增大而增大；与无初始转角相比，有初始转角的橡胶隔震支座水平刚度较大，使得其在地震设防烈度下的隔震效果较差；在工程受力范围内，3种不同水平位移加载下，竖向压力的变化对水平刚度的影响较小。
In order to analyze the bearing rotation of large-span spatial structures,the horizontal mechanical properties of the rubber bearings with relative rotation between upper and lower faces were studied. The finite element software ABAQUS was used to analyze the horizontal mechanical properties of rubber bearings without initial rotation. Then the horizontal mechanical properties of rubber bearings with initial rotation were analyzed when the horizontal displacement loading in ？？X？？ direction, ？？Y？？ direction and 45° direction. Finally, the varying trends of horizontal stiffness and shear strains were obtained. The results show that when shear strains are small, the horizontal stiffness of bearings decreases with the increases of the rotation at first, and then increases at ？？X？？ direction and 45° direction. When shear strains are large, the horizontal stiffness decreases with the increases of the rotation angle at first, and then increases at ？？Y？？ direction.Comparing with rubber bearings without initial rotation, the horizontal stiffness of the rubber bearings with initial rotation is larger, which makes the seismic isolation effect under seismic fortification intensity worse. In the range of engineering stress, the vertical pressures have little effect on the horizontal stiffness under three different horizontal displacement loading directions