Research and Development of Damping Device for Light Weight Mechanical Structure Using Damping Effect Caused by Eddy Current

2009 ◽  
Author(s):  
Osamu Furuya ◽  
Keiji Ogata ◽  
Toyohiko Tanaka ◽  
Hiroshi Kurabayashi
Keyword(s):  
Eddy Current ◽  
Base Isolation ◽  
Low Cost ◽  
Control Technique ◽  
Small Scale ◽  
Light Weight ◽  
Isolation System ◽  
Seismic Safety ◽  
Damping Effect ◽  
Kobe Earthquake

A base-isolation and vibration control technique has been applied positively to architectural and civil structures after Kobe earthquake, and now the techniques are adopted as general vibration reduction technique for many structures. In such situation, an application of the vibration attenuation device to the small-scale structure has been carried out actively in recent years. Especially, in the important institution of the cities such as a refuge place, a hospital, a school, an information and a communication institution where function maintenance is needed, it is important to maintain its performance of the machinery and equipment in the facility with an upgrade of structural seismic safety. Moreover, in the future, upgrading of seismic safety of the particular equipments is urgent business. This study has been examined a low cost and compact damping device for base-isolation system of light weight mechanical structures like a computer server rack. In this paper, the experimental and analytical results on the basic performances of the damping device using damping effect by Eddy-Current.

Performance Evaluation of Product Type Magnetic Damper Using Eddy-Current Damping Effect

2011 ◽  
Author(s):  
Osamu Furuya ◽  
Keiji Ogata
Keyword(s):  
Eddy Current ◽  
Base Isolation ◽  
Low Cost ◽  
Vibration Reduction ◽  
Product Type ◽  
Small Scale ◽  
Isolation System ◽  
Seismic Safety ◽  
Damping Effect ◽  
Kobe Earthquake

Response control techniques such as a base-isolation and a vibration control have been a general vibration reduction system for upgrading of seismic safety or habitability improvement in civil and architectural structure after Kobe earthquake. In such state in Japan, an application of the vibration reduction device to a small-scale structure has been carried out actively in recent years. Especially, in the important institution of the cities such as refuge place, hospital, school, information and communication institution where function maintenance is needed, it is important to maintain its performance of the machinery and equipment in the facility with an upgrade of structural seismic safety. Moreover, in the future, upgrading of seismic safety of the particular equipments is urgent business. This study has been examined a compact and low cost damping device for a base-isolation system of light weight mechanical structures like a computer server rack. In this paper, experimental and analytical results on the performances of the product type damping device using damping effect caused by Eddy-Current are described.

Laminated Type Isolation Device for Light Weight Structure Using Urethane Elastomer

2017 ◽  
Author(s):  
Kengo Goda ◽  
Osamu Furuya ◽  
Kohei Imamura ◽  
Kenta Ishihana
Keyword(s):  
Seismic Isolation ◽  
Base Isolation ◽  
Light Weight ◽  
Loading Test ◽  
Isolation System ◽  
Seismic Safety ◽  
Base Isolation System ◽  
Weight Structure ◽  
Isolation Device ◽  
Urethane Elastomer

At the present, base isolation system has been recognized by general earthquake resistant technique since the Great Hanshin Earthquake 1995. The seismic isolation will be aggressively applied to not only architectural and civil structures but also various structures, because the effectiveness on seismic safety had been demonstrated again in the Great East Japan Earthquake. In generally, although the base isolation system is divided into laminated rubber bearing type and friction sliding bearing type. In the case of former type, shape factor, maximum or minimum outer shapes and so on are restricted by the material characteristics in visco-elastic material. In general, the isolation structure is used in high damping rubber. However, we pay attention to base isolation using urethane elastomer. Urethane elastomer has excellent elasticity, mechanical strength, abrasion resistance, weather resistance, oil resistance, impact resistance the absorbent, anti-vibration and excellent low-temperature properties. Furthermore, it is possible to impart various characteristics by a combination of isocyanate and polyol and chain extender, requires no large-scale apparatus, it has the advantage molecular design is easy. In previous study, the research and development of laminated type base isolation device using urethane elastomer was carried out to upgrade a seismic safety for various structures. The fundamental characteristics was investigated from several loading test by using various experimental devices, and the design formula for the stiffness and equivalent damping coefficient is formulated as an approximate expression of mechanical characteristics until now. It was confirmed that urethane elastomer is not hardening up to 500% shear strain. Moreover, the experimental examination for aged deterioration in the urethane material has been continuously carried out. As the results, it was confirmed that the laminated type seismic isolation device using urethane elastomer is possible to develop as a practicable device from the stable mechanical properties as considering in design step. In this study, the small-scale laminated type base isolation device using urethane elastomer is advanced to the direction of further technical upgrading and of scale down for light-weight structure as a sever rack. The first stage, basic properties of the urethane elastomer has been investigated by loading test. Furthermore, the design equation is created by loading test using urethane elastomer. The validity of the design equation has been confirmed. The second stage, the compression creep test with laminated type base isolation device has been investigated to confirm an effect on light-weight mechanical devices.

Study on Simple Vibration Attenuation System for Light Weight Structure

2007 ◽  
Author(s):  
Osamu Furuya ◽  
Hiroshi Kurabayashi
Keyword(s):  
Large Scale ◽  
Base Isolation ◽  
Scale Structure ◽  
Small Scale ◽  
Response Analysis ◽  
Light Weight ◽  
Seismic Safety ◽  
Small Scale Structure ◽  
Vibration Attenuation ◽  
Weight Structure

Various vibration attenuation methods such as a base isolation and vibration control are suggested as seismic safety technique for large scale architectural and civil structure, and these methods have been practical used now. In recent years, these vibration reduction technology begins to be applied to a small scale structure. In case that the technology is applied to a small scale structure, specifications and a cost of the device must be examined well. In this study, a vibration attenuation system for light weight structure with low cost and simple mechanizm. This paper describes the effectiveness of the proposed vibration attenuation system which was evaluated from preliminary seismic response analysis.

Study on Small-Scale Laminated Type Base Isolation Device Using Urethane Elastomer for Practical Application

2016 ◽  
Author(s):  
Kenta Ishihana ◽  
Osamu Furuya ◽  
Kengo Goda ◽  
Shohei Omata
Keyword(s):  
Seismic Isolation ◽  
Mechanical Characteristics ◽  
Base Isolation ◽  
Small Scale ◽  
Loading Test ◽  
Isolation System ◽  
Seismic Safety ◽  
Base Isolation System ◽  
Isolation Device ◽  
Urethane Elastomer

At the present, base isolation system has been recognized by general earthquake resistant technique since the Great Hanshin Earthquake 1995. The seismic isolation will be aggressively applied to not only architectural and civil structures but also various structures, because the effectiveness on seismic safety had been demonstrated again in the Great East Japan Earthquake. In generally, although the base isolation system is divided into laminated rubber bearing type and friction sliding bearing type. In the case of former type, shape factor, maximum or minimum outer shapes and so on are restricted by the material characteristics in visco-elastic material. In previous study, the research and development of laminated type base isolation device using urethane elastomer was carried out to upgrade a seismic safety for various structures. The fundamental characteristics was investigated from several loading test by using various experimental devices, and the design formula for the stiffness and equivalent damping coefficient is formulated as an approximate expression of mechanical characteristics until now. The mechanical characteristics based on the loading test up to 500% shear strain using experimental specimen with 100 × 100 mm cross-sectional shape. It was confirmed that urethane elastomer is not hardening up to 500% shear strain. Moreover, the experimental examination for aged deterioration in the urethane material has been continuously carried out. As the results, it was confirmed that the laminated type seismic isolation device using urethane elastomer is possible to develop as a practicable device from the stable mechanical properties as considering in design step. In this study, the small-scale laminated type base isolation device using urethane elastomer is advanced to the direction of further technical upgrading and of scale down for light-weight structure as a sever rack. The first stage, basic properties of the urethane elastomer has been investigated by loading test. The second stage, the compression creep test with laminated type base isolation device has been investigated to confirm an effect on light-weight mechanical devices.

scholarly journals A small-scale, low-cost isolation system for the incubation and rearing of low bacterial load chicks as a model to study microbial–intestinal interactions

2008 ◽  
Vol 42 (2) ◽  
pp. 185-192 ◽  
Author(s):  
Rebecca E A Forder ◽  
Gordon A Firth ◽  
David R Tivey ◽  
Gordon S Howarth ◽  
Robert J Hughes
Keyword(s):  
Low Cost ◽  
Bacterial Load ◽  
Small Scale ◽  
Isolation System

scholarly journals Low Cost Frictional Seismic Base-Isolation of Residential New Masonry Buildings in Developing Countries: A Small Masonry House Case Study

2017 ◽  
Vol 11 (1) ◽  
pp. 1026-1035 ◽  
Author(s):  
Ahmad Basshofi Habieb ◽  
Gabriele Milani ◽  
Tavio Tavio ◽  
Federico Milani
Keyword(s):  
Finite Element ◽  
Seismic Vulnerability ◽  
Base Isolation ◽  
Low Cost ◽  
Element Model ◽  
Shaking Table ◽  
Fe Model ◽  
Isolation System ◽  
Finite Element Software ◽  
Non Linear

Introduction:An advanced Finite Element model is presented to examine the performance of a low-cost friction based-isolation system in reducing the seismic vulnerability of low-class rural housings. This study, which is mainly numerical, adopts as benchmark an experimental investigation on a single story masonry system eventually isolated at the base and tested on a shaking table in India.Methods:Four friction isolation interfaces, namely, marble-marble, marble-high-density polyethylene, marble-rubber sheet, and marble-geosynthetic were involved. Those interfaces differ for the friction coefficient, which was experimentally obtained through the aforementioned research. The FE model adopted here is based on a macroscopic approach for masonry, which is assumed as an isotropic material exhibiting damage and softening. The Concrete damage plasticity (CDP) model, that is available in standard package of ABAQUS finite element software, is used to determine the non-linear behavior of the house under non-linear dynamic excitation.Results and Conclusion:The results of FE analyses show that the utilization of friction isolation systems could much decrease the acceleration response at roof level, with a very good agreement with the experimental data. It is also found that systems with marble-marble and marble-geosynthetic interfaces reduce the roof acceleration up to 50% comparing to the system without isolation. Another interesting result is that there was little damage appearing in systems with frictional isolation during numerical simulations. Meanwhile, a severe state of damage was clearly visible for the system without isolation.

Seismic performance of a Low-Cost base isolation system for unreinforced brick Masonry buildings in developing countries

2021 ◽  
Vol 141 ◽  
pp. 106501
Author(s):  
Daniele Losanno ◽  
Nagavinothini Ravichandran ◽  
Fulvio Parisi ◽  
Andrea Calabrese ◽  
Giorgio Serino
Keyword(s):  
Developing Countries ◽  
Seismic Performance ◽  
Base Isolation ◽  
Low Cost ◽  
Brick Masonry ◽  
Masonry Buildings ◽  
Isolation System ◽  
Base Isolation System

Study on Laminated Type Base Isolation Device Using Urethane Erastomer for Practical Application

2015 ◽  
Author(s):  
Kenta Ishihana ◽  
Osamu Furuya ◽  
Kengo Goda ◽  
Shohei Omata
Keyword(s):  
Mechanical Characteristics ◽  
Base Isolation ◽  
Approximate Expression ◽  
Response Analysis ◽  
Loading Test ◽  
Cross Sectional ◽  
Isolation System ◽  
Seismic Safety ◽  
Isolation Device ◽  
Urethane Elastomer

Base isolation system will be aggressively applied to not only architectural and civil structures but also various structures, because the effectiveness on seismic safety had been demonstrated again in the Great East Japan Earthquake. In this study, the research and development of laminated type base isolation device using urethane elastomer has been carried out to upgrade a seismic safety for various structures. The fundamental characteristics have been investigated from several loading test by using various experimental devices, and the design formula for the stiffness and equivalent damping coefficient is formulated as an approximate expression of mechanical characteristics until now. Moreover, the experimental examination for aged deterioration in the urethane material has been continuously carried out. This paper summarizes the mechanical characteristics based on the loading test up to 500% shear strain using experimental specimen with 100×100 mm cross-sectional shape, base isolation effect from time response analysis using nonlinear element model of urethane elastomer and the accelerated aging test for verifying the aging of practical use.

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