新型叠层橡胶隔震支座的承载特性研究

Study on the Bearing Capacity of a New Rubber Isolation Bearing

提出了一种可以减小支座拉应力,增大极限变形能力的新型变截面叠层橡胶隔震支座,根据体积相等的原则建立新型叠层橡胶隔震支座和普通叠层橡胶隔震支座两种有限元模型,通过理论推导给出了变截面橡胶隔震支座屈曲应力随水平位移的关系,研究了新型支座竖向反力分布、屈曲应力及极限剪切变形等承载特性,指出:在相同的竖向荷载与水平位移的条件下,新型支座的最大拉应力减小了30%以上;新型支座的有效承压面积在剪切变形前期保持稳定,后期一直大于普通支座;普通支座要比新型支座更易进入屈曲状态;新型支座的极限水平位移大于普通支座。

A new variable cross-section laminated rubber isolation bearing was proposed in this paper in order to reduce the bearing＇ s tensile stress and to increase the ultimate horizontal deformation. The finite element model for both new variable cross-section laminated bearing and the ordinary one were established according to the same volume. The relationship between buckling stress and horizontal deformation derived from theoretical analyses was given. Through the study on the vertical reaction force and buckling stress distribution and the uhimated horizontal deformation, it is pointed out that the maximum tension stress of the new bearing can be reduced more than 30% under the same vertical load and horizontal displacement. The effective loading area of the new bearing remained stable at the early stage of horizontal deformation. After that, the effective loading area of the new bearing kept larger than that of the ordinary bearing. The ordinary bearing shows earlier buckling feature. The ultimated horizontal deformation of the new bearing is greater than that of the ordinary one.