Numerical Simulation And Experimental Study Of Vibration Reduction Of Suspension Bridge Based On Viscous Damper

Wind-induced vibration with different mechanisms of long-span bridges will occur under strong winds.The primary problem that must be solved for the further development of bridges is to restrain the vibration of bridges.Wind resistance measures are mainly tuning damping fo r existing bridges.However,as the span of the bridge increases,especially the span of the sus pension bridge has already spanned several kilometers.For the fundamental frequency is smal l,the damping is low,and the vibration of various modes,the method which tuning the dampi ng to suppress its large vibration has been difficult to adopt.Based on the composite damping cable damping technology,the relative motion of the pylon and the main beam is used to drive the damper energy dissipation in order to reduce its vibration,which can greatly increase the damping ratio of the bridge and suppress its multi-order vibration.The numerical simulation a nd experimental research are executed for this purpose.the main research content includes:(1)Using the eddy current damper as the energy consuming element,the relationship between the viscous coefficient of damper and the number of magnets was obtained through experime nts.(2)Fabricating the suspension bridge-damper cable mode,the relationship between the install ation position of the damping cable,the viscous coefficient of the damper and the additional d amping ratio of the bridge was measured,the effect of the composite damping cable on the vi bration reduction of the suspension bridge was verified,and the optimal high span ratio of the damping cable is obtained.(3)The finite element model of suspension bridge-damper cable is established.the relationshi p between the high span ratio of the damping cable,the viscous coefficient of the damper and the additional damping ratio of the bridge is also analyzed.The comparison with the model te st data verifies the accuracy of the ANSYS numerical calculation model.(4)Using ANSYS model to analyze the vibration reduction of a low tower suspension bridge and Xihoumen bridge by composite damping cable damping,and studied the vibration dampi ng effect of the bridge which under free vibration,forced vibration and strong wind excitation by changing the high span ratio of the damper and the viscous coefficient of the damper.The optimal viscous damping coefficient and the damper cable height-to-span ratio are obtained.