Shaking table tests of bridges isolated by sliding bearings

Presented in this paper is shaking table tests of bridges isolated by 4 different sliding bearings in order to identify the seismic response with emphasis on the frictional characteristics of the sliding bearings, effects of vertical and transverse excitation and the difference of frictional coefficient, and generation mechanism of vertical load at the sliding bearings. The test results showed that the combinations of vertical and horizontal excitation as well as longitudinal and transverse excitation generated larger responses compared with merely longitudinal excitation in case of sliding bearings with high frictional coefficient and high velocity-dependency, and that the effect of the 4 different frictional coefficients on the maximum and residual displacement became clear. Furthermore, it was found that shear keys at rubber buffers might affect vertical reaction force at the sliding bearings.