STAYED-CABLE PARAMETRIC VIBRATION BY CONSIDERING THE EFFECT OF BRIDGE DECK AND TOWER

摘要

Towards wide-range cable vibration of large-span cable stayed bridge, taking cable-deck-bridge tower spatial couple into account, dimensionless nonlinear vibration equations of cable are educed under the excitation of end deck and bridge tower, and solved by elaborate time-history integration. It is found that cable vibration property is related to ratio of cable, deck and bridge tower and initial disturbance of deck and bridge tower. 1:1 inner resonance occurs and bat of cable appears, when the ratio of natural frequency of cable and deck or bridge tower is nearly 1 but far away 2. 2:1 parametric resonance occurs and divergence of vibration displacement of cable appears, when the ratio of natural frequency of cable and deck or bridge tower is nearly 2. 1:2 ultra harmonic resonance occurs and steady vibration appears, when the ratio of natural frequency of cable and deck or bridge tower is nearly 1/2.