Evaluation of tensile characteristics of rubber bearings to design seismically isolated structure by design limit value of tensile strain

Generally, in the case of designing seismically isolated structure, tensile design limit value for laminated rubber bearing is defined by tensile stress. The critical value is defined as 1 MPa independent of type of rubber bearing. However, in case seismically isolated structure is designed using design limit tensile stress value, tensile stress often transcends 1 MPa. If tensile stress transcends design limit tensile stress, special device which can avoid generation of tensile deformation is used. This becomes an obstacle to designing seismically isolated structure. In order to alleviate this obstacle, the method which tensile design limit value is defined by tensile strain is proposed in this paper. First, outline of tensile test condition to define design limit value of tensile strain and its test result are shown. Next, design limit value of tensile strain and tensile modulus is proposed. Finally, prediction accuracy by FEM analysis for tensile deformation of laminated rubber bearing is verified.