The damper for vibration mitigation of stay cable is developed in this study. Developed damper is such a led-shear type and it is installed at the inside of cable system not seen at the outside. Developed damper has advantages of maintenance free, hig...
The damper for vibration mitigation of stay cable is developed in this study. Developed damper is such a led-shear type and it is installed at the inside of cable system not seen at the outside. Developed damper has advantages of maintenance free, high durability and gives much additional damping to stay cable. To achieve above purpose, mathematical models for damper and cable-damper system are established and, using these models, additional damping and vibration mitigation effect by damper are analysed. Design methods for lead-shear damper are proposed with two types such as general and optimal methods. The applicability of proposed design methods are verified by applying those methods to real stay cable of cable-stayed bridge. These methods are also applied to the design of test RVD (prototype of lead-shear damper) and cable. Proposed mathematical models of cable-damper system and design methods are verified by the laboratory experiments. These lead-shear damper is a prototype named RVD (Robinson Vibration Damper). The hysteresis test results and mathematical model of RVD are compared for the verification purpose of mathematical model. The mathematical model of cable-damper system is verified by comparing with the test results of cable-damper system which is designed by proposed method. Finally, test methods for the verification of designed damper in the real structures are suggested. These methods are adopted to the stay cable of Seohae bridge and are examined the applicability to the real structures. In design and manufacture of lead-shear damper, another important point is that the lead core fully behaves in the state of shear action. If this is not satisfied, lead core deforms by bending and does not give much additional damping to the stay cable because of increasing stiffness by large damper force compared with damper displacement. When considering the above important facts, developed lead-shear damper may give much additional damping to stay cable and the proposed design methods is straightforward when designing the lead-shear damper.