STUDY ON BASED-ISOLATION OF WOODEN HOUSESBY HEAT HARDENING PORYURETHANE RUBBER

摘要

This paper investigates effectiveness and mechanical characteristics of heat hardening polyurethanerubber (PUR) for viscoelastic dampers in based-isolated and vibration controlled wooden houses. SincePUR shows low stiffness and high damping compared with the conventional viscoelastic materials, it issuitable for based-isolated device for small-scale structures such as wooden houses. In addition, PUR isnot expensive so it is possible to build up based-isolated system in low cost. From the results of sinusoidalloading tests of PUR, the mechanical characteristics are estimated. PUR has frequency dependency, straindependency, temperature dependency, and axial pressure dependency. Especially in them, axial pressuredependency is important. Because there is the problem of axial pressure dependency that equivalentstiffness of PUR increases with the increment of pressure, when it is used as based-isolation device. TheKelvin-Voigt model is build up based on the results of test. In this study, laminated PUR bearing isproposed to control axial pressure. From the results of vibration test for the laminated PUR bearing, lowequivalent stiffness and high equivalent viscous damping factor is observed even if axial pressure exists.The results of seismic response analysis show the effectiveness of laminated PUR bearings for basedisolatedstructures.