This paper reports the vibrational behavior and unstable phenomena of multi-connected bodies supported by damper-spring elements moving in a narrow flow passage. These vibrational phenomena have been often observed in high-speed trains running in tunnels, cleaning robots going through pipings, medical machines in human blood vessels and core internal structures in nuclear reactor vessels. The fluid forces acting on the multi-connected rigid bodies are obtained analytically on the basis of the Navier-Stokes equations applied to a narrow flow passage. After the equations of coupled motion of the multi-connected bodies and fluid are derived, a stability analysis is performed, taking physical dimensions such as gaps etc. as parameters.

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In this paper, the dynamic stability of gas-lubricated journal bearing with Herring-bone groove are investigated. The pressure distribution which is generated in compressible fluid at the gap in the bearing is calculated. The equation of motion is derived using the fluid force and fluid moment acting on journal which is calculated from the pressure distribution. On the basis of the derived equation, the numerical simulation of the dynamic behavior of the journal is performed. The vibrational mode and the stability of the behavior of the journal are investigated. Finally parameter studies are discussed.

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This paper shows vibration behavior of a circular cylinder subjected to jet-flow from a narrow gap in the vicinity of wall by using computational fluid dynamics (CFD) simulation. We investigated the effects of the distance between the centerline of jet-flow and the cylinder center. And these CFD simulation results are comparred with the experiments in published paper. As a result, the vortex shedding vibration phenomena and the fluid elastic vibration phenomena can be confirmed in a circular cylinder subjected to jet-flow from a narrow gap as well as in the case of the experiment.

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This paper deal with the frequency responses of stable planar motions in a partially filled cylindrical tank with an eccentric core barrel. In theoretical analysis, the nonlinearity of the liquid surface oscillation and the nonlinear coupling between the dominant modes and other modes are considered in the response analysis of the sloshing motion. And, the governing equation of the amplitude of liquid surface motions are derived, and the stability analysis is conducted. An experiment was carried out using a model tank. The theoretical results of the frequency responses of the liquid surface displacements agree well with the experimental results.

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A previously reported slosh analysis method is applied to the sloshing problem for a teardrop tank with non-axisymmetric static liquid domain. For a rotating tank, a mechanical model cannot be developed for a certain direction of tank excitation since the Coriolis acceleration causes coupling between the slosh motions in two orthogonal directions that are parallel to the static liquid surface. This problem is solved by developing mechanical models for the two orthogonal directions under the gravity and centrifugal forces and introducing coupling terms resulting from the Coriolis acceleration such that the eigenfrequencies of the coupled system coincide with the slosh eigenfrequencies that are determined by another proposed slosh analysis method including the Coriolis acceleration.

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Vibration Tests with large-amplitude sinusoidal excitation was performed for examining the coupling effects between beam vibrations and oval vibrations on a scale model of cylindrical water storage tank, which were classified as fluid-structure coupling vibrations. As a result, any resonance points of beam vibrations disappear from their expected frequency range. The response of the tank did not intensify in proportion to the input acceleration, and moreover, did not go beyond a certain level. The coupling effects were considered to lower the flexural rigidity of the tank, and an analytical model was proposed, whose flexural rigidity depends on the magnitude of the oval vibrations.

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This paper deals with self-excited vibrations of overflow pipes due to fluid discharge. In this study, the experiments and analysis are carried out to determine the relation among the lag time, the inflow rate, the flow velocity, the fluid force at elbow part and fall height of the fluid falling along the vertical pipe. The excitation mechanism of the self-excited vibrations is discussed experimentally and theoretically.

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Spatial behavior of the pipe conveying fluid is examined theoretically and experimentally under the condition that the rotational symmetry is broken by the asymmetric spring supported end. When the flow velocity is over its critical value and has the small pulsating component, the interaction of the self-excited vibration and parametric excitaiton are occured. Four first-order ordinary differential equations, which govern the amplitudes and phases of the pipe vibration, are derived from the nonlinear nonself-adjoint partial differential equations by the liapnov-schmidt reduction. The planar motion, the beating and chaotic motions of the pipe vibration exist depending on the value of the pulsating frequency and the perturved parameter of the spring coefficient. Furthermore the experiments were conducted with the silicon rubber pipe conveying water. The spatial displacement of the pipe was measured by the image processing system which was based on the images from two CCD cameras.The typical feature of the pipe vibration,which has been predicted in the theory ,was confirmed qualitatively.

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It is known that the fuel pulsation caused by fuel pump or injectors is generated for vehicle fuel line. This fuel pulsation caused noise and deterioration of engine performance. Therefore, estimating this pulsation in an early stage of development is hoped. So, we developed the fuel pulsation analysis method by using 1D fluid flow analysis software. Firstly, piping, fuel damper, pressure regulator, and injector that are main parts for fuel line were modeled. Secondly, simple bench models were constructed by using models of parts and calculated. Comparing the experimental results with the calculation results, the propriety of this method was confirmed.

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Differential pressure transmitters with an orifice are widely used as field flow meters. The typical trouble of the differential pressure transmitters under operation is an impulse line blockage. Thus, the authors develop a detecting method of the impulse line blockages using the R.M.S. value of fluctuations of measured pressures. This method always monitors not only the fluctuation of differential pressure but also those of two static pressures, which means the high side pressure and low side pressure. The experimental investigations show that this monitoring makes it possible to detect a both side blockage and either side blockage before the blockages have an serious influence on measuring the differential pressure.

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In this study, the root blower was applied to the low pressure gas supplying pipe with a reciprocating compressor to reduce the pulsation. It was clarified that the root blower reduced the amplitude of pressure more than the tank with same volume, and did not reduce flow. The reduction mechanism of the root blower is thought that it absorbs the energy from pulsation as fluid resistance. Then, the energy turns the blade without the external power and fluid is transported. It is concluded that the root blower is better than a orifice and a tank as the pulsation reduction device.

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Narrow annular flow causes vibration of the structures such as elastic beam in the narrow annular flow. The vibration becomes larger. In this paper, active control of the axisymmetric elastic beam subjected to narrow annular flow is investigated. The fluid-structure coupled equation based on the Euler-Bernoulli type partial differential equation and Navier Stokes equation are derived including control terms. In this paper, the piezoelectric-type actuator is used to control the coupled system. Applying the optimal control law to the coupled system, the unstable behavior is stabilized. To know the value of the state vector from the observed data, the observer is employed. The simulation studies are performed to investigate the efficiency of the proposed control method and the effect of the position of actuator on control performance.

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This paper deals with a theoretical and experimental study of active feedback control of leakage-flow-induced sheet flutter. Leakage-flow-induced sheet flutter are suppressed by the feedback to the injection (and drawing) of the fluid at the inlet or outlet of the passage. The stability boundary, displacement of the system with the active control is examined with varying the controller gain and phase-shift angle. As a result, it is indicated experimentally and theoretically that leakage-flow-induced sheet flutter are suppressed.

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This paper deals with the active control of flow induced vibrations generated in flexible dump diffusers. The flow induced vibrations are suppressed by the feedback to the injection of the fluid at the inlet of the passage. The instability boundary of the system with the active control is examined with varying the controller gain and phase-shift angle on the vibration displacement signal. As a result, it is indicated experimentally that the active feedback control technique suppresses the flow induced vibrations effectively.

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This paper studies disturbance cancellation control to suppress vortex-induced vibration of a circular cylinder in a cross flow. Fluctuating lift force acting on a vortex-induced cylinder is assumed as a disturbance. An observer was constructed to estimate the disturbance. Two different types of disturbance are assumed to describe the fluctuation of vortex shedding. One is a sinusoidal wave and the other is a wake oscillator represented by the van der Pol equation. Control performances of both types of disturbance model were examined by simulation and experiments.

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Tube bundles are used in heat exchangers and inner reactor components, and the flow field around the tube bundles contains cross and parallel flow components. Fluid-elastic vibration should be evaluated for tube bundle in the flow with the cross flow component. When critical velocity of fluid elastic vibration is evaluated for the tube bundle in the mixed cross and parallel flow, the parallel flow hardly affects the vibration characteristics, and normally only cross flow is taken into account. However, very few studies were conducted to evaluate the flow velocity distribution of mixed cross and parallel flow. In this study, water tunnel tests under mixed parallel and cross flow conditions were preformed to understand the influence of the balance of parallel and cross flow component on vibration response. It was found that the critical flow velocity for self-excited vibration was not influenced by parallel flow component, and depended only on the cross flow component.

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In the present paper the attention is focused on the vortex shedding from in-line tube banks on acoustic resonance which occurred in the two-dimensional model of boiler. We measured a spectrum, phase delay of velocity fluctuations in the tube banks, sound pressure level. As a result it was made clear that the symmetric pair of vortices were clearly formed even in the case of Reynolds number, based on mean gap velocity, of about 1.1×104 with acoustic resonance in the longitudinal direction of the duct. Strouhal number, based on mean gap velocity and vortex shedding frequency, was 0.52.

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This paper describes the confirmation of countermeasure's effect for flow-induced vibration in a shell & tube type heat exchanger. This type heat exchanger has often used in the LPG gas carrier ship and has sometimes caused a fretting and finally comes to a fatigue failure. In this paper, the clip is adopted as the countermeasure and it is clarified that the clip can suppress the tube vibration drastically. In this experiment, another countermeasure, that is to say, the dummy tube array is also examined. However the fluid elastic instability occurs by use of dummy tube array. The reason is described in detail.

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This paper deals with an experimental study of vortex-induced vibrations of bellows structure subjected to fluid flow. The characteristics of the vortex-induced vibrations, strohal number St and mass damping parameter Sc are examined experimentally with changing the pitch length, the number of flexible convolutions and the convolution shapes. The fluid flow around the vibrating convolutions is visualized and the structure of the vortex street is clarified. As a result, it is found that the lock-in phenomenon occurs to the bellows structure by in-phase and out-of-phase mode due to the coupling between the vibration of the convolutions and vortex streets generated along the convolutions.

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The separation of mixture consisting of three kinds of plastic was studied experimentally and analytically. The principle behind the separation technique is based on the difference in Coulomb force acting on the plastic particles after triboelectric charging. The mixture is charged by friction in a mixer and is separated in a vibratory feeder equipped with two plate electrodes. The separation tests were performed on a sample containing polyvinylchloride (PVC), polyethylene terephthalate (PET) and polystyrene (PS). The charging distribution of plastic particles was measured. An analytical solution is provided to estimate the recovery of plastics. It is shown that it is possible to obtain high purity and recovery of plastics.

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In this report, the validities of nonlinear vibration analysis by the Galerkin's method using linear natural modes and the Incremental Transfer Stiffness Coefficient Method, which is presented by authors, are checked quantitatively from view points of computational accuracy and computation speed. Generally, a vibration behavior of a large-scale system is estimated from analysis result of a reduction model obtained by applying the Galerkin's method using linear natural modes to a large-scale system. By this sort of method, in order to execute accurate analysis, computation time tends to increase explosively. In this report, supremacies of both methods are clarified at various computation conditions.

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It is well known that the vibration and the noise of agricultural machinery during running on a road is strongly influenced by the lug form of the tire. Many studies were carried out on the characteristics of Automobile Tire, but few studies have been carried out on Agricultural Tire. In this research, the vibration characteristics of an Agricultural Tire was studied by experimental modal analysis method. Furthermore, the tire was modeled as a thin, cylindrical beam and the fundamental values of the tire were identified by the optimized method. Finally, the effects of the fundamental values of the tire on natural frequencies were investigated.

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This work deals experimentally with the countermeasure against squeal phenomena generated in mountain bike disk brakes. In previous our work, it was made clear that the squeal is in-plane vibration in the direction of disk surface with frequency 1kHz caused by the frictional characteristics with negative slope with respect to the relative velocity generated in the vibration system including brake components and spokes. A dynamic absorber was attached to hub in order to control squeal, and its validity was confirmed by using a bench apparatus. From experimental and analytical results, optimal parameter of damping ratio, the natural frequency, and the effect of mass ratio of dynamic absorber is established.

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The vibration supression becomes very important for designing the helicopter blades to ensure the comfortability and safety. Now-a-day, the pendulum absorbers and others are adopted for the purposes to reduce the vibration of the rotor blades.In a Helicopter, periodic forces act on the blades due to the influences of the air thrust. These periodic foreces act on the blades with their integer multiple of the rotational speed of the rotor. But, the drawback is that the dimension of the pendulum absorbers is determined by the anti-resonance concept based on the linear theory, and also its characteristics were not analyzed in detail. We had proposed a two-degree-of-freedom model of the rotor blades and the pendulum absorbers, and it clarifyed analytically vibration-proof effect of the pendulum absorbers on these forces. In this paper,we confirm the effect of the pendulum absorbers by experiments and simulations.

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The aim of this work is producing the disc brake that the squeal is not generated fundamentally. A design manual of the disc brake considering support methods and support positions of caliper was proposed. On the other hand, a dynamic absorber was attached to a basic self-excited vibration system caused by Coulomb's friction, and optimal parameters of dynamic absorber which controls the squeal were studied analytically. Moreover, optimal dynamic absorber from analysis was attached to an experimental apparatus, and the effectiveness of the dynamic absorber was confirmed

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To prevent residual vibrations of a flexible structure in positioning control, an acceleration input pattern without natural frequency components of the structure is preferred. Most of the window functions used in signal processing have good properties as their higher order frequency components are small. In this paper, advantages of window-function-shaped acceleration patterns are clarified by numerical simulations of a theoretical model for open loop positioning control. Some of the patterns can make the amplitude of residual vibration infinitesimal and they are robust over the variation of system parameters.

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An inspection of a flaw of a helical heating tube installed in a fast breeder reactor MONJU in Japan is operated by a feeding of an eddy current testing (ECT) probe with magnetic sensor into the tube. An undesirable vibration of the ECT probe always happens under a certain condition and makes the inspection difficult. Several characteristics of the vibration have been clear through some experiments by using a mock-up. However, an essential factor of the vibration is still unclear. In this paper, the motion of the probe is described in a polar coordinate along the helical tube and a numerical simulation of the vibration is implemented on the assumption that the vibration is caused by the Coulomb's friction. The results of simulation qualitatively agree well with the experimental results. It confirms the validity of the assumption that the vibration is caused by the Coulomb's friction.

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There is a problem of undesirable vibration of flaw detection probe in a helical tube installed in a prototype fast breeder reactor. Probes modeling and algorithm for numerical simulation were proposed in the precious report and simulation results were same as mock-up experimental results qualitatively. This paper deal with the vibration generation mechanism and the effectiveness of a variety of vibration control plan by using numerical simulation. Confirming the control effect by the numerical analysis leads to the saving of cost and time.

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The chattering behavior of end-mill shank was measured by two laser Doppler vibrometer from the feed and radial directions at the same time when end-milling of the hardened steel. As a result, it could be confirmed that there are two kinds of chatter vibrations that vibrating modes and frequency different depending on cutting speed. We proposed the chattering model that could be accounted with the dependence of cutting force on cutting speed and the coupled action in feed and radial directions.

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Free vibration of a pendulum supported asymmetrically is considered. We found that a pendulum supported asymmetrically changes its swinging direction during free vibration, and spatial motion occurs. Deriving the equation of motion and analyzing it, it is found that this phenomenon is a kind of parametric excitation. It is shown form numerical simulation that various spatial motions occur depending on initial condition and magnitude of asymmetry of the system. Experimental analysis is also conducted, which confirms the validity of the theoretical analysis.

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A method of simulation of the bending vibrations of plates was presented already by the author. In the method, analytic solutions are used. The bare bones of this method is to satisfy approximately boundary conditions using the collocation method. The analytic solutions expressed in the plane polar coordinate system are used. The method shows a good efficiency and a good accuracy. However, we need more examples of examination in order to establish the reliability of this method. In this paper, the simulation and the experimental results about plates with partially clamped edges are shown.

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As a means to determine accurate boundary conditions, experimental identification techniques attract interest of engineers and many techniques have been proposed. This study aims to propose a technique which does not require measurement of excitation data. It is imposed on the new technique to require neither the measurement nor the application of excitation at the boundaries. In the proposed technique, the boundaries are modeled by springs and dampers as well as equivalent mass and moment of inertia, and their characteristics are determined by the harmonic balance method. Experiments are conducted to confirm the applicability of the technique.

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This paper describes the separation and transportation of works with various friction coefficients using elliptical vibration. Elliptical vibration machine has a horizontal vibratory system and a vertical vibratory system. Transportation velocity is depends on amplitude, phase difference and friction coefficients. When a friction coefficient differs by form or material of works, transportation velocity is changed also including the direction of positive/negative, even if elliptical vibration machine has same amplitude and phase difference. Using this phenomenon, works with which different friction coefficients can be separated by transporting difference direction.

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In the blood pressure measurement, the auscultatory method that is standard and an easier method by the automatic sphygmomanometer are used widely. It is known that the measurement results by the two methods are sometimes rather different. In order to investigate the cause of the phenomenon, a linear model with single degree of freedom is made for the structure from the blood vessel wall to the cuff in this study. The model is assumed that it has the time varying coefficients because the blood vessel expands and contracts periodically. The method to identify them by using an optimization method was proposed and the effectiveness of it is shown by the identification results.

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Welding is widely used for construction of many structures. It is well known that residual stress is generated near the bead because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. Some reduction methods such as heat treatment and shot peening are practically used. Authors have proposed a new method for reduction of residual stress using vibration during welding. In this paper, filtered whiter noise is used considering noise is used as input signal. Two thin plates are butt welded and residual stresses near the bead are measured. It is found that tensile residual stresses near the bead are reduced when filtered white noise is used as vibratinoal load during welding. The proposed method is examined by simulation method using analytical model of the specimen. From the simulation method, it is demonstrated that tensile residual stresses near the bead are reduced when filtered white noise is used during welding.

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This paper describes the performance of Transient Statistical Energy Analysis (TSEA) for impulsive responses on the beam structures. The properties of response predicted by TSEA are discussed especially in the relation between the response and the loss factors. In order to understand how to measure the subsystem energy transfer which can be compared with the prediction by TSEA, the impulsive responses on two beam structures which are composed of two steel beams with different coupling strengths are measured. As a result, the measurement for responses and excitation should be done at the mean location in a subsystem. Finally, it is shown that the TSEA predictions have good agreement with the measured responses especially in high frequency and in the weak coupling structure.

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Stochastic jump phenomena in the random responses of a Duffing oscillator subjected to narrow band excitation are investigated. In the case of hardening stiffness, large and small amplitudes of the responses correspond in phase, and 180 degrees out of phase with the excitation, respectively. But, the phase angle between the excitation and the response is difficult to calculate when the band width of excitation becomes broader. In this study, we calculate the product of each wavelet transform of excitation and response, and demonstrate that the quantity can be used as the alternative to the phase angle.

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Fig. A2 Comparison of theoretical and experimental results Fig.A1 Analytical model of air spring Table A1 Dimensions of the air spring shown in Fig.A1In this paper, we analyzed a rolling seal type air spring with an orifice. Two types of damping (viscous damping and non-viscous damping) through the orifice are taken in our analysis. The experimental result shows that the air spiring with circular orifice reveals the non-viscous damping characteristics.

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Recently, semi-active vibration control devices have been utilized to various structural design problems. Magneto-Rheological(MR) damper that use MR fluids is one of semi-active vibration control devices. In most of past report, no damping force of MR damper has been evaluated. These methods can confirm the effect of damping. However, it has not been examined whether MR damper can produce required design damping force. So, in this paper, I focus attention on damping force and examine the improvement of the MR damper. I also confirm the influence of precipitation of MR fluids on damping force.

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Experimental investigation into the dynamic behavior of vibration system with granular materials has been carried out using forced vibration system with one degree of freedom. Results from the experimental tests indicate that the vibration systems containing granular materials show the vibration damping characteristics. We measured vibration response under several foundations' acceleration conditions. Vibration tests were performed on various types of conditions for the granular materials. The mass and diameter of the granular materials were changed as the parameters. The experimental tests indicate that the damping ratio increases when the mass of the granular materials increases. And then at the optimum mass of granular materials, damping ratio shows maximum value. Furthermore, we proposed the concept of "additional mass" of granular materials. The damping effect is discussed in relation to this "additional mass".

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The magnetic damper in this paper is based on the Lorentz force by Fleming's left-hand rule. That is to say, the direction of the force is the opposite of that of the relative velocity between the conductor and the magnet, and moreover, the directions of the velocity and that of the magnetic field are at right angle with each other. The magnetic damper we propose is composed of a ball magnet and a conductor that has a unique shape that a semispherical-shell is combined with a hollow cylinder. The magnetic damper has some good points that the space for a damper-mechanism can be small, and it can have the possibilities to improve damping capacity. We report the simplified damping tests to two kinds of this magnetic damper.

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It has been reported by the authors that recent actual lightweight railway vehicle car bodies have complex flexural vibration shapes. The mode shapes of commuter vehicles are complex in particular, with the roof and floor moving out of phase from each other. Such complicated vibration often worsens the riding comfort. In order to reduce such vibrations, especially those with large relative deformation between roof and floor, a new vibration reduction device has been developed. The new vibration reduction device, which is called SPD (stanchion pole damper), looks similar to ordinary stanchion pole, but it connects the main structure of roof and floor and it has built-in viscous damper. Four SPDs are applied to actual commuter vehicle car body and stationary vibration test is carried out to confirm the validity of SPDs. From the test results, it is shown that the SPD can reduce the flexural vibration of the car body successfully.

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In this paper, the authors propose a vibration control device using power generator in order to develop a small damper which was suitable for structural vibration control in space. The vibration control device consists of a ball screw, piston, ball nut, gear, power generator, and rod ends. The linear motion of the piston is converted to rotary motion by the ball screw, and then the electric power is generated as dissipation energy. A very low sinusoidal input displacement was applied to the device, and the characteristics of the damping force were examined with open circuit and short circuit of the generator. The experimental results were compared with the theoretical results.

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This paper deals with the vibration suppression method for actual railway carbody by using Piezoceramics elements. In order to investigate this problem based on shaking test , numbers of elements which should be attached on various position of the body are required. In this report, an advanced attachment method is proposed by improving the attachment devices. After carrying out tests by using two types of proposed devices, it becomes clear that effective vibration suppression can be obtained by the improvement of attachment device.

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A new energy regenerative and active control vibration damper is introduced. The energy regenerative damper has nonlinear characteristics with dead zone for low speed motion. Hence PWM set-up chopper has been introduced to overcome this problem. But the regenerated energy is not used. A combined control of regenerative and active is proposed in this paper. The optimum control force is calculated using LQ theory and put out to the developed circuit. The PWM switchs are driven in proportion to the difference between the optimum control force and the actuator force. The proposed damper is applied to an active mass damper system. A simple experimental setup is fabricated and tested for the proposed technique. The results show an increase in performance as compared with the previously proposed software controlled regenerative and active control damper.

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Many hemiplegias use Ankle-foot orthosis to prevent falling when they walk. In order to support natural walking of hemiplegias, we develop a new ankle foot orthosis by using self-powered semi-active damper. A DC motor and step-up chopper circuit is used to regenerate energy. Theoretical analysis for electrical circuit and energy generation and gait experiment using this ankle foot orthosis are carried out. From the experimental results, it can be seen that this system can generate 80 percent of the consumed electric power.

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In the previous paper, the authors proposed a new type of dynamic vibration absorber using a three-layered cantilever beam, called moment-type dynamic vibration absorber, which suppress the moment caused by the vibration of a three-layered cantilever beam. The three-layered beam consists of two copper plates and viscoelastic material. In this paper, the effects of vibration suppression of a moment-type dynamic vibration absorber using a three-layered cantilever beam to a primary simply supported beam is discussed theoretically and experimentally, and compared with an ordinary-type dynamic vibration absorber which has the same mass ratio.

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The swing of a gondola lift is easily induced by wind and can be reduced by a dynamic absorber. When the conventional dynamic absorber is located at the center of gravity of the main mass, the swing is not reduced at all. Therefore the absorber should be located as high as possible. In this paper, a new type dynamic absorber which moves radially is proposed. The swing is reduced by coriolis force when dynamid absorber moves radially. It is effective even if the absorber is located at the center of gravity of the main mass.

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A new type of dynamic vibration absorber using semicircular arc beams has been developed. The purpose of this study is the examination for responses of the high rise reinforced concrete stack with the absorber. The analytical parameters of the absorber for the stack are mass ratio and frequency ratio of the absorber to the stack, and damping ratio of the absorber. The effect of response reduction is examined by frequency response, earthquake response, and wind response analyses.

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In the previous paper, the authors proposed passive and hybrid dampers using a lever-type displacement magnifying mechanism. In this paper, a new type of dynamic vibration absorber using the lever-type magnifying mechanism was proposed. The optimum condition of the dynamic vibration absorber was determined numerically, and the transmissibility of the primary system with the absorber was calculated. The calculated result was compared with that for a conventional type absorber system, and the effect of the magnifying mechanism was confirmed. The trial dynamic vibration absorber was made, and the frequency responses and the seismic responses of a primary system with the trial absorber were measured. The experimental results were compared with the calculated results, and the effects of vibration suppression of the absorber and the validity of the calculations were confirmed.

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