Wall-type viscous shear damper High performance damper with excellent durability suitable for protecting high-rise buildings. Advantages It is effective for absorbing a wide range of vibrations, from wind vibration to violent shaking caused by strong earthquakes. VWD can be designed to suit the scale of the building and vibration damping required. No maintenance is required as the viscous fluid remains stable over many years, and there is absolutely no leakage of fluid. Structure and Function The Oiles Viscous Wall Damper is a vibration attenuator using the shear resistance force of a highly viscous fluid. It consists of outer steel container filled with a viscous fluid and an internal shearing plate. The relative storey displacement induced by an earthquake or a strong wind produces movement of a shearing plate fixed to the upper beam relative to the viscous fluid container fixed to the lower beam. The resistance created by the movement of the shear plate in the viscous fluid effectively absorbs the vibration energy. Oiles viscous fluid Oiles viscous fluid is a high viscosity material, which has superior heat resistance, environmental resistance, as well as durability. It provides a stable resisting force during cyclic shearing without viscosity degradation. Basic Features This chart shows the relationship between force and displacement when VWD is subjected to the motion expected during a major earthquake. Design values correlate well with actual measurements indicating stable performance and accurate design methods. The hysteresis loop of VWD produces a smooth curve, test results indicate stable damping is achieved during motion from small amplitude low speed vibration to large high speed shaking. Test Performance Test Basic performance tests of a VWD from low to high speed demonstrated that a stable damping function could be obtained during motion from small amplitude low speed vibration to large high speed shaking. Seismic response wave Test Response to a seismic wave was tested to verify the characteristics of VWD for actual buildings during a major earthquake. Results show actual measurement coincide with calculated values, verifying safety in a major earthquake.