Oiles (japan)

This study develops a hysteresis model for lead rubber bearings (LRBs) using Bouc-Wen (BW) model and particle swarm optimization (PSO). Bilinear model often overestimate response acceleration, whereas BW model offers more accurate nonlinear hysteresis behavior. Static cyclic loading tests on LRB specimens validated the model. Parameters of BW model were optimized via PSO, and a simplified parameter determination method was proposed. Key parameters such as initial stiffness, secondary stiffness, and yield displacement can be accurately driven by existing formula, while parameters related to unloading stiffness and stiffness transition are newly proposed in this study.

電気制御を用いて免震層特性を暴風時と地震時で完全に独立させ，高摩擦板を用いることで大地震後のメンテナンスを不要とする耐風ロック機構を開発した．本耐風ロック機構のシステム構成を説明し，制動材として用いる高摩擦材の要素試験と実大の制動力確認試験により，所定の性能を有することが確認できた．さらに複数台の油圧ジャッキを用いた作動試験を実施することで，1つのポンプに複数台のジャッキが接続されていても，昇圧時間と降圧時間に差はなく同時に作動するため，耐風ロック機構として問題なく作動することを確認できた．

After Great East Japan Earthquake in 2011, the base load power in Japan was shifted from nuclear power to coal-fired thermal power. Stable electricity supply is one of important infrastructure, so improvement of seismic reliability of coal-fired thermal power plant and related structures is very important. Boiler structures in coal-fired thermal power plants are generally high-rise structures, and boilers in the structures are usually hung on the top of the structures in order not to restrict thermal expansion. Therefore boilers easily vibrate by earthquakes. In order to suppress vibration of boilers during earthquakes, stoppers made of steel are installed between boilers and support structures. The stoppers have simple mechanism and dissipate vibration energy by plastic deformation of steel material. However, further improvement of vibration control performance is required from the viewpoint of above-mentioned social requirements and recent large earthquakes such as the Great East Japan Earthquake, the Kumamoto earthquake in 2016 and so on. This study proposes an application of a damper using viscous fluid to boilers of coal-fired power plants. The damper is set between boilers and support structures. There are many examples of application of the damper using viscous fluid to buildings and civil engineering structures. Therefore the application of the damper to boilers will be effective. In this paper, a seismic response analysis using an analysis model of a boiler structure is conducted. The analysis model has plural stoppers or plural dampers. The response analysis result is evaluated from the viewpoint of vibration control performance. In other words, story shear force of the support structure is evaluated. In addition various limitations such as the maximum stroke of the dampers are taken into account. As a result, story shear force of the support structure with the proposed damper is smaller than that of the structure with the conventional stopper made of steel, so the proposed damper has high vibration control performance.

Various types of dampers are being utilized to reduce building vibrations due to earthquakes. For a viscous or viscoelastic damper of brace configuration, the companion paper (Part 1) proposed the theory and method to quantify influence of the damper component stiffness on dynamic properties of damper. This paper (Part 2) considers another configuration like wall or panel, which is more complex because of the shear force and bending moment causing complicated deformation of the components. Theories and methods for damper property assessment are proposed. They clarify that deformation and interactions among damper components can cause significant loss of damping effect. The approximate method shows excellent accuracy, and can be used to create the models for assessment as well as practical time-history analysis of the damper and the building damping system.

This paper proposes a new type of active seismometer measuring vibration possessing long period and wide dynamic range. In order to lower the natural frequency and expand the detectable amplitude, the sensor with the low natural frequency is realized by using feedback control. Moreover, to compensate phase-delay, third order phase-lag compensator is added to shape measured output. It has been demonstrated that the detectable frequency range of the sensor is extended from 0.1 [Hz] to 10[Hz], while the dynamic range of that is expanded up to 57[dB], namely vibrations that possess 700times larger amplitude than the maximum stroke of the sensor. New sensor body is produced and tested.

Response control devices are widely used at the design of high-rise buildings owing to reduce the seismic response considering about the influence of long period ground motion, but these performances are degraded by excessive bending deformations. In order to improve response control performance, this paper describes an analysis method of effective damper deformations and a new structural system which amplifies effective damper deformations. It is confirmed that this system is able to highly reduce responses, particularly in acceleration and shear force, with a small amount of damper owing to high damping effect.

Olive oil is an integral ingredient of the Mediteranean diet. The effects of extra virgin olive oil (EVOO) on triglyceride metabolism were investigated by measuring the degree of thermogenesis in interscapular brown adipose tissue (IBAT), and the rates of noradrenaline and adrenaline secretions in rats, both in vivo(Experiment 1) and in situ(Experiment 2). In Experiment1, rats were given an isoenergetic high-fat diet containing corn oil, refined-olive oil or EVOO for 28 days. The phenolic contents in refined-olive oil and EVOO were 0 and 141mg (oleuropein aglycone 104mg)/kg respectively. After 28 days of feeding, the final body weight, perirenal adipose tissue, and epididymal fat pad and plasma triglyceride concentrations were the lowest in rats fed EVOO diet. The content of UCP1 in IBAT and the rates of urinary noradrenaline and adrenaline excretions were the highest in the rats fed the EVOO diet. In Experiment 2, the intravenous administration of oleuropein and oleuropein aglycone significantly increased plasma noradrenaline and adrenaline concentrations. Furthermore, oleuropein aglycone induced the secretions of noradrenaline and adrenaline about ten fold more potently than oleuropein. These results suggest that the phenolic compounds, oleuropein and oleuropein aglycone in EVOO enhance thermogenesis by increasing the UCP1 content in IBAT and noradrenaline and adrenaline secretions in rats.

It is necessary to clarify the characteristics of the ideal viscous fluid material to examine a characteristic model of the viscous fluid damper of the various shapes. Here the small size testing equipment was used in consideration of the steel stiffness, the work efficiency and so on. But the correct grasp of the characteristic from the measured values with that equipment was difficult, because these values were not the ideal forces and were affected by the scale effect. Therefore, inspecting those unexpected forces and grasping the ideal values are important. First of all, part1 shows the method to consider properties of viscous fluid material under ideal condition with experiment and analysis, and the test outcomes performed in extensive strain, temperature and frequency.