斜拉索内置式高阻尼橡胶减振器性能研究OA

To mitigate wind-induced vibration of stay cables,a built-in shear-type high-damping rubber absorber was developed.The shock absorber featured a compact structure,eliminated the need for embedded plates,and had minimal impact on the overall bridge deck aesthetics.Small-strain model tests using high-damping rubber blocks under shear deformation were conducted to investigate the relationships of their mechanical parameters with strain,frequency,and fatigue recovery.A mechanical model of the stay-cable-high-damping rubber shock absorber system was established.Based on the model test results,vibration reduction analysis was conducted.The effectiveness of the shock absorber was validated through field testing on an actual bridge.The results showed that under shear strains below 30%,the shear modulus of the high-damping rubber was less than 3.0 MPa,and the loss factor consistently exceeded 0.35.After high-cycle,low-strain fatigue testing,the storage shear modulus and loss factor decreased by 26.1%and 0.8%,respectively.After an intermission,the mechanical parameters of the rubber blocks largely recovered to their pre-loading levels,and their critical loading cycle number exceeded 31000 cycles.As the stay cable length increased,the optimal shear area required for the shock absorber decreased progressively,and the optimal damping coefficient provided by the shock absorber increased correspondingly.Field testing on the actual bridge demonstrated that the shock absorber achieved a 97%reduction in vibration acceleration amplitude,and the root-mean-square acceleration was lower than the Level 1 exceedance threshold of 0.1019g specified in the cable monitoring standard.