damping of a full-scale cable with a pair of passive–on magnetorheological (mr) dampers was tested. a cable of 215.58m long with the first mode frequency of 0.658hz was tensioned horizontally in cable prefabrication factory. two mr dampers were attached to the cable in an angle in the plane perpendicularly to the cable axis in 5m length from the cable anchorage. the applied voltage level was 0v...

structural dynamic parameters: natural period, shape modes and damping ratio of vibration, play a decisive role on the seismic behavior of those structures. there are several methods for determining of the structural dynamic parameters, such as: free vibration, ambient vibration and force vibration tests. in this research the structural response of a three-story building (the natural frequencie...

Excessive vibration of turbomachinery blades causes high cycle fatigue (HCF) problems requiring damping treatments to mitigate vibration levels. Based on the technical challenges and requirements learned from previous turbomachinery blade research, a feasibility study of resonant damping control using shunted piezoelectric patches with passive and active control techniques has been conducted on...

For advanced aerospace propulsion systems, development of ceramic matrix composite integrally-bladed turbine disk technology is attractive for a number of reasons. The high strength-to-weight ratio of ceramic composites helps to reduce engine weight and the onepiece construction of a blisk will result in fewer parts count, which should translate into reduced operational costs. One shortcoming w...

The aim of the present work is to study the effect of annealing on the vibration damping capacity of high-chromium (16%) ferromagnetic steel. The alloys were prepared from raw materials of 99.9% purity melted in a high frequency induction furnace under high vacuum. The samples were heat-treated in vacuum at various temperatures (800 to 1200oC) for 1 hour followed by slow cooling (120oC/h). The ...

Research on shunted piezoelectric transducers, performed mainly over the past decade, has generated new opportunities for control of vibration and damping in flexible structures. This is made possible by the strong electromechanical coupling associated with modern piezoelectric transducers. In vibration control applications, a piezoelectric transducer is bonded to, or embedded in a base structu...

To facilitate the damping matching of dampers for vehicle passive suspensions, this paper proposes an analytical matching method of the optimal piecewise linear damping characteristics curve. Based on the vehicle vibration model, taking the suspension dynamic deflection as the constraint, by the vibration acceleration and the wheel dynamic load, an objective function about the relative damping ...

Innovative magnetorheological dampers (MR dampers) for shock and vibration damping, based on magnetorheological fluids (MRFs), are described. Important fields of their application are loading processes, impact dampers in security systems as well as vibration dampers for machines and cars. Various models for describing the MR dampers are discussed. The characteristic feature of the MR dampers is...

The connection of two building structures with dampers is one of the effective vibration control systems. In this vibration control system, both buildings have to possess different vibration properties in order to provide a higher vibration reduction performance. In addition to such condition of different vibration properties of both buildings, the connecting dampers also play an important role...

In the design of high Quality factor (Q) micro or nano beam resonators, different dissipation mechanisms may have damaging effects on the quality factor. One of the major dissipation mechanisms is the thermoelastic damping (TED) that needs an accurate consideration for prediction. In this paper, thermoelastic damping of the longitudinal vibration of a homogeneous micro beam with both ends clamp...