Optimal Placement of Viscous Dampers in Super Tall Buildings Based on Grid Shear Velocity

摘要

Due to its excellent lateral stiffness and space flexibility, the frame-core wall structures are widelyapplied in super high-rise buildings. Energy dissipation technology can be applied in tall buildingsto reduce the seismic responses of main structures and realize optimal structural design for themain structure. As an effective energy dissipation device, viscous damper can generate dampingforce by viscosity effects of the viscous liquid. Due to its velocity-dependent nature, viscousdampers can be applied to dissipate seismic energy under different earthquake levels, evenfrequent earthquake with small seismic responses. The number of viscous dampers in certainproject is commonly limited due to budget constraint, and it is always desirable that the viscousdampers are to be installed in those places which can maximize the energy dissipation duringearthquake. Story drift was employed as an index for the optimal placement of viscous dampers incurrent tall building design practices in China. This study proposed to use grid shear velocity(GSV) as the index for the optimal placement of viscous dampers. The GSV is better than storydrift in two aspects: one is that the GSV reflects the velocity-dependent nature of the viscousdamper, the other is that the rigid body velocity component is excluded. An optimal viscousdamper placement method was developed based on GSV in this study. A 10 floor frame structureand a super tall building located in high seismicity area were employed as examples to show theeffectiveness of the proposed GSV method. The results show that the optimal viscous placementsobtained by the proposed GSV method match well with the theoretically best placements whichcan maximize the energy dissipation. The proposed GSV method can be generally applied for theoptimal placement of viscous dampers in super tall buildings.