HIGH PERFORMANCE PASSIVE HYDRAULIC DAMPER WITH SEMI-ACTIVE CHARACTERISTICS

This paper presents an ingenious passive hydraulic damper for structural control with high performance equivalent to that of a semi-active damper. This damper maximizes or minimizes the damping coefficient by regulating the opening of a flow control valve housed in the device, and absorbs much of the structure’s vibration energy than a conventional passive viscous damper. The remarkable feature of this device is that all the valve control is carried out autonomously utilizing the pressure balance between two hydraulic chambers without any outer power resources. First, we explain the self-regulating hydraulic mechanism. Second, we present the results of dynamic loading tests on a full-scale prototype device (maximum force: 2MN) under both sinusoidal waves and non-stationary seismic response waves. It is thus confirmed that the developed device has the expected excellent energy dissipation capacity, and that the damper’s dynamic characteristics can be well simulated by a simple analytical model. Finally, we demonstrate the results of seismic response analyses using an MDOF building model, and discuss the control performance of the device.