SHAKING TABLE TESTS OF BRIDGES ISOLATED BY SLIDING BEARINGS

Abstract

Presented in this paper is shaking table tests of a bridge isolated by four different sliding bearings in order to investigate the seismic response with emphasis on frictional characteristics of the sliding bearings with different sliding materials, the effect of vertical, transverse excitation and the frictional coefficient difference on seismic responses, and the generation mechanism of vertical force variation at the sliding bearings. The test results showed that combinations of vertical and horizontal excitations as well as longitudinal and transverse excitations generated larger responses compared with merely longitudinal excitation in case of a sliding bearing with high frictional coefficient and large velocity dependence, and that the effect of the four different frictional coefficients on the maximum and residual displacement became clear. Furthermore, it was found that shear keys at rubber buffers might affect vertical force variation at the sliding bearing.