| Abstract: | The vertical response of suspension bridges to multi-support seismic excitations is investigated. A frequency-domain random-vibration approach is utilized to take into account not only the differences in ground motion inputs, but also the correlation among the various input motions. The earthquake response of the Golden Gate Suspension Bridge, California, is analysed. The ground motion inputs were taken from an array of time histories recovered from the Imperial Valley, California, earthquake (ML = 6.6) of 15 October 1979. Mean square displacement, stress and cable tension responses are obtained. An estimation of the expected peak response is made by comparing existing methods to the results of a time-domain analysis; it was found that a peak factor of 3.5 times the r.m.s. response is a good estimate of the expected peak response for this multiple-input seismic problem. |
