板式橡胶支座的水平位移特性

Horizontal Displacement Characteristics of Plate Rubber Bearing

为研究曲线梁桥板式橡胶支座在实际运营过程中的受力特性和水平位移发展规律。通过Abaqus建立矩形板式橡胶支座GJZ 500×600×130的有限元模型,对比模型与理论计算的剪切刚度说明了模型的正确性,基于此模型进一步对支座在单次和多次循环位移加载作用下来研究支座水平位移变化规律,然后考虑曲线梁桥板式橡胶支座实际受力情况进行加载,研究支座在变化的竖向压力荷载作用和考虑静动摩擦转变等情况下的位移变化特性,并分析了支座在长期重复荷载作用下的残余变形的发展规律。结果表明:通过此方法建立的支座有限元模型能够较好地模拟支座与上部结构之间的摩擦行为,精确的计算支座的剪切变形和滑动位移;动态的竖向压力作用对支座剪切变形阶段基本不受影响,但对滑动变形阶段有较大大的影响;支座由静摩擦转变为动摩擦时,其水平力和剪切变形会突然减小;支座的残余变形会随着加载次数的增加而累积增大,但增长幅度随着加载次数增长而减小。

In order to study the mechanical characteristics and development law of horizontal displacement of rubber bearing of curved girder bridge slab during actual operation.The finite element model of rectangular plate rubber bearing GJZ 500×600×130 was established by using Abaqus,and the shear stiffness of the model was compared with the theoretical calculation value to demonstrate the correctness of the model.The horizontal displacement of the bearing was studied under the action of displacement load,and then the bearing was loaded considering the actual force of plate rubber bearing in curved beam bridge.The transition between vertical pressure load and static friction force and dynamic friction force was studied.The characteristics of bearing and the development law of residual deformation under long-term repeated load were analyzed.The results show that the finite element model of bearing established by this method can better simulate the friction behavior between bearing and superstructure,and accurately calculate the shear deformation and sliding displacement of bearing.The dynamic vertical pressure is basically unaffected in the shear deformation stage of the bearing,but has a great influence on the sliding deformation stage.When the support changes from static friction to dynamic friction,its horizontal force and shear deformation will suddenly decrease.The residual deformation of the support will increase cumulatively with the increase of loading times,but the increase rate decreases with the increase of loading times.