Passive Energy Dissipation System With Polymer Damping Materials For Stay Cables Vibration Control

At present, with the increase of the span of constructed cable-stayed bridges, thestay cables become longer and longer. It is necessary for the construction and servicesof cable-stayed bridges with the large span to mitigate the large vibration of the staycables. It is well known that passive vibration control is one of the popular reductionapproaches of the stay cables. However, considering the effects of all of factors on thedynamic properties of the controlled stay cables, the analysis and design theories of thepassive control of the cable vibration needed to be further developed. Meanwhile,presently, polymer damping materials has been widely used for the noise cancellationsystem due to its excellent performance, low cost and high damping energy-dissipationcapacity. However, the polymer damping materials have not been used for civilengineering vibration control. Therefore, some investigations on the polymer dampingpassive energy dissipation system to reduce the stay cables vibration of the cable-stayedbridge are proposed.Theoretical analysis along with experimental investigation are conducted on thefollowing research topic:On the basis of the shearing energy dissipation principle of polymer dampingmaterials - dimethyl silicone oil, one shearing passive damper with the variable widthsingle slot is developed. Under different loading amplitude and frequency, performancetests are carried on the designed damper with the different width of the single slot. Theperformance testing results indicate that the developed damper based on the polymerdamping materials has high energy dissipation capacity and its mechanical performanceis stable. In addition, the performance testing results show that the thickness of theviscous body in the single slot and the configuration of the clapboard have a significanteffect on the damping force.Based on the research of the designed passive damper with the single slot,one fullsize shearing passive damper with multi-slots is designed. The mechanical performancetests of the designed full size damper have been conducted. The performance testingresults have been analyzed to confirm that the shearing passive damper with thepolymer damping materials has superior damping performance. According to the experimental results analysis of the mechanical properties of thedeveloped damper, the model of the damping force has been established using theparameter identification method. The influence of the parameters of the establisedmodel on the damping force has been analyzed systematically. The analysis resultsshow that the rigidity coefficient and damping coefficient of the passive damper withpolymer damping materials are affected by the loading frequency and amplitude.Utilizing the established damping force model of the passive damper with polymerdamping materials, a general design approach, which could be used by the practicalengineering conveniently, is proposed for the passive energy dissipation system toreduce the stay cables vibration of the cable-stayed bridge, considering the influence offactors, such as stiffness and nonlinearity of passive damper,sag and bending stiffnessof stay-cables.