Summary: | 碩士 === 國立臺灣科技大學 === 營建工程系 === 95 === The design formulas of viscous dampers given in the current design provisions such as FEMA and NEHRP, the connecting braces are assumed to be rigid such that the deformation is concentrated in the dampers. However, the flexibility of the connecting braces of viscous dampers may reduce the damping contribution to the structure. Therefore, some previous study has provided a stiffness requirement for proportioning the connecting braces. However, in some cases, the stiffness requirement may result into so large a size of brace that is impractical in construction.
Since the strength rather than the stiffness is normally used as the design target for the braces, the study has derived a design formula together with a design procedure for determining the damping coefficient of viscous dampers so that the design target damping ratio can still be obtained and the connecting brace is simply designed according to the load capacity of the viscous damper. The proposed formula has provided a simple guideline for rationally increasing the damping coefficient of the viscous damper considering the flexibility of the connecting braces and can be used as a supplement to the existing design formulas of viscous dampers given by the current design provisions.
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