Study on friction support to increase seismic performance of piping systems subjected to multi-directional inputs

通过大尺寸三维管道模型的振动试验，研究了库仑摩擦模型扩展到二维的有效性。将建立的二维库仑摩擦模型应用于管道模型的地震响应分析，提出了一种基于模态分析的方法。通过与试验结果的比较，验证了所提出的二维库仑摩擦模型的有效性以及所提出的摩擦振动模态分析方法的实用性。其次，研究了同时输入，即振动台输入和管端位移输入对带摩擦支承的管道模型响应的影响。为了研究上下运动对水平方向库仑摩擦模型的影响，利用小型振动台对悬臂梁进行了上下和水平同时运动的振动试验。试验结果表明，不同的法向载荷对摩擦阻力有一定的影响。

The validity of Coulomb's friction model extending to two dimension is investigated by vibration test of a large scale three dimensional piping model with frictional sliding motion in plane at the frictional support. By employing the established two dimensional Coulomb's friction model to the seismic response analysis of the piping model, a method using modal analysis is proposed. The validity of the proposed Coulomb's friction model of two dimension and the usefulness of the proposed method using modal analysis of frictional vibration are confirmed by comparing the analysis result with the test result.Next, the influence of simultansous inputs, i.e.the input of vibration table and the input of displacement on pipe's end, on the response of the piping model with friction support is investigated.In order to examine the effect of up-and-down motion on the Coulomb's friction model of horizontal direction, the vibration test of a cantilever beam subjected to simultansous up-and-down and horizontal motions is conducted by using small vibration table. From this test, it is shown that some ratio of varied normal load affects the friction force.