Volume 8: Seismic Engineering最新文献

{"title":"Variable Inertia Damper Using a Flywheel Filled by MR Fluid","authors":"T. Matsuoka","doi":"10.1115/pvp2019-93093","DOIUrl":"https://doi.org/10.1115/pvp2019-93093","url":null,"abstract":"\u0000 To get a variable inertia effect for vibration reduction, a semiactive damper using a flywheel filled by MR fluid was developed. The damper comprises a ball screw mechanism and the flywheel, which is able to change a moment of inertia. MR fluid is filled into the flywheel. Particles are clustered at outer circumference edge inside the wheel when the magnetic field is applied to the wheel edge, so the moment of inertia on the flywheel can be changed artificially. The prototype device was manufactured, and the dynamic performance was investigated. Finally the changeable inertia effect was confirmed experimentally.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125472349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of Uplift Displacement of Tanks due to Out-of-Round Deformation of Cylindrical Shell","authors":"Yoshiyuki Miyauchi, T. Taniguchi, T. Nakashima, Junichi Hongu, D. Okui","doi":"10.1115/pvp2019-93254","DOIUrl":"https://doi.org/10.1115/pvp2019-93254","url":null,"abstract":"\u0000 Two unanchored vinyl chloride scale tank models, whose diameter, height and thickness of their shell and base were 860 mm, 400 mm and 0.5 mm respectively, were set on a shaking table for experiencing the horizontal motion. These scale tank models satisfy law of similarity to have an equivalent strain under the action of loads.\u0000 The first scale tank model has no stiffeners on its cylindrical shell that allows out-of-round deformation of the cylindrical shell during the shaking table test. To understand effects of the out-of-round deformation of the cylindrical shell on the tank uplift, the sweeping test is carried out. The Operational Modal Analysis clarifies that the out-of-round deformation of the cylindrical shell enhances the uplift displacement by denting a part of cylindrical shell.\u0000 The second scale tank model has the multi-stage stiffeners on its cylindrical shell to prevent its out-of-round deformation during the shaking table test. The primary purpose of the second test is to verify applicability of the explicit finite element analysis for analyzing the tank rocking motion. The time history of the uplift displacement of the tank base during a seismic excitation is measured and compared with that computed by the explicit finite element analysis. The comparison shows that the explicit finite element analysis adequately reproduces the tank rocking behavior.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125146281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applicability of Seismic Fatigue Evaluation by JSME Code Case, NC-CC-008","authors":"Akihito Otani, Izumi Nakamura, Tomoyoshi Watakabe, M. Morishita, T. Shibutani, M. Shiratori","doi":"10.1115/pvp2019-93123","DOIUrl":"https://doi.org/10.1115/pvp2019-93123","url":null,"abstract":"\u0000 A Code Case, JSME S NC1, NC-CC-008, in the framework of JSME Nuclear Codes and Standards has been published. New seismic evaluation methodology for piping by utilizing advanced elastic-plastic response analysis method and strain-based fatigue criteria has been incorporated into the code case. It can achieve more rational seismic design than the current rule.\u0000 This paper demonstrates validity and applicability of fatigue evaluation method proposed in the code case. Experimental results of a shaking table test for a piping model is used for comparing the evaluation by the current rule with one by the code case. As a result, it is confirmed that the code case can provide a rational and conservative result in the fatigue evaluation of piping. Moreover, cycle counting in the fatigue evaluation was examined for further progress of the code case.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128898961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Kriging-Based Surrogate Model for Seismic Fragility Analysis of Unanchored Storage Tanks","authors":"H. Phan, F. Paolacci, D. Corritore, N. Tondini, O. Bursi","doi":"10.1115/pvp2019-93259","DOIUrl":"https://doi.org/10.1115/pvp2019-93259","url":null,"abstract":"\u0000 The seismic vulnerability of aboveground steel storage tanks has been dramatically proved during the latest seismic events, which demonstrates the need for reliable numerical models for vulnerability and risk assessments of storage facilities. While for anchored aboveground tanks, simplified models are nowadays available and mostly used for the seismic vulnerability assessment, in the case of unanchored tanks, the scientific community is still working on numerical models capable of reliably predicting the nonlinearity due to uplift and sliding mechanisms. In this paper, a surrogate model based on a Kriging approach is proposed for a case study of an unanchored tank, whose calibration is performed on a three-dimensional finite element (3D FE) model using a reliable design of experiments (DOE) method. The verification of the 3D FE model is also done through a shaking table campaign. The outcomes show the effectiveness of the proposed model to build fragility curves at a low computational cost of the critical damage state of the tank, i.e., the plastic rotation of the shell-to-bottom joint.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129993739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Study of Near-Fault Effect on Sloshing Mode of Storage Liquid in Tanks","authors":"J. Chai, F. Lin, Wei-Hung Hsu, Tzu-Chieh Chien, Zhihong Lai, Zhen-Yu Lin","doi":"10.1115/pvp2019-93388","DOIUrl":"https://doi.org/10.1115/pvp2019-93388","url":null,"abstract":"\u0000 The long period velocity pulse is recognized as one of the characteristics of near-fault ground motions, and hence the response of vibration modes with lower frequencies will be amplified owing to the resonant effect. In general, the sloshing frequency of storage liquid is low and the period is similar to the pulse period of near-fault ground motions. Compared to the far-field ground motions, the induced sloshing height will be amplified by the near-fault ground motions. Therefore, it is worth paying attention to the resonant effect of near-fault ground motions on the sloshing mode of storage liquid in tanks.\u0000 An experiment was implemented to study the resonant response of sloshing mode. The purpose of this experiment is to estimate the slosh height and the associated total volume of water splashing out of the tank under near-fault ground motions, and also to determine the relationship between the resonant response and the input velocity pulse. This paper aims to describe the test plan in detail, and it consists of (1) design of the scaled storage tank and water depth, (2) selection and processing of the input motions including the original near-fault ground motions, extracted velocity pulse or extracted bandpass signals for resonance analysis, and also impulse motion for free vibration, (3) setup of measure instrument, and (4) the experimental procedures as well. Preliminary analysis results are compared with the code-specified values that is determined by the industrial standards and guidelines for general seismic conditions. It is noted that the proposed prediction equation can be applied to the seismic design and evaluation of spent fuel pool in nuclear power plants.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134204012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ratcheting Behaviour of 3D Printed and Conventionally Produced SS316L Material","authors":"R. Halama, M. Pagáč, Zbyněk Paška, Pavel Pavlíček, Xu Chen","doi":"10.1115/pvp2019-93384","DOIUrl":"https://doi.org/10.1115/pvp2019-93384","url":null,"abstract":"\u0000 This paper shows some differences in stress-strain behavior of conventional and 3D print SS316L. First, the influence of strain rate on the monotonic curve has been investigated. Specimens produced by Selective Laser Melting technology were not so sensitive to the strain rate. Viscoplasticity has to be taken into account for cyclic loading modelling in the case of conventionally produced SS316L but not for the 3D printed material.\u0000 A set of low-cycle fatigue tests was performed on specimens from both used production technologies. Uniaxial ratcheting tests were realized under constant amplitude of stress and varying mean stress. Experimental results show a good ratcheting endurance of SS316L produced by the Selective Laser Melting technology. Biaxial ratcheting tests were realized for 3D print SS316L only. Applied Digital Image Correlation technique makes possible to get more ratcheting curves from each ratcheting test.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125527619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Deformation of Core Elements of Fast Reactor Core to the Seismic Response","authors":"Akihisa Iwasaki, Shinichiro Matsubara, K. Kawamura, Hidenori Harada, Tomohiko Yamamoto","doi":"10.1115/pvp2019-93769","DOIUrl":"https://doi.org/10.1115/pvp2019-93769","url":null,"abstract":"\u0000 Core elements of a fast reactor are self-standing on the core support structure and not restrained in the axial direction. When the earthquake occurs, it is necessary to consider vertical behavior and horizontal displacement of the core elements simultaneously. In the core seismic analysis, a three dimensional core vibration behavior was evaluated by considering fluid structure interaction, collision with adjacent core elements and vertical displacement and verified by a series of vibration tests. But the evaluation had a assumption of straightness of each core elements which may be bowed due to thermal expansion and swelling under restraint of the horizontal direction between the upper pad and lower structure (Entrance Nozzle). If the core elements are deformed in its plant operation, they may push each other against its adjacent core elements. The large horizontal interference forces may work to decrease the vertical displacement of the core elements.\u0000 In this study, to grasp and estimate the behavior under the deformed core elements under the earthquake motion, a three dimensional seismic analysis model consist of all of core elements with consideration of the effect of deformed core elements were prepared, analyzed and verified by hexagonal-matrix tests with 37 core elements and single row mock-up models with 7 core elements. These test results show that the rising displacements decrease with increased deformation and no rising occurs when the deformations exceed a threshold.\u0000 In this paper, the effect of bending deformation due to thermal expansion and swelling on the rising displacement of the core elements was shown by seismic experiments.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122615665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic Evaluation Methods for Fire Protection Sprinkler Piping Systems in Buildings","authors":"F. Lin, J. Chai, Y. Tsai, Chang-Chen Yeh, Kuo-Chun Chang","doi":"10.1115/pvp2019-93443","DOIUrl":"https://doi.org/10.1115/pvp2019-93443","url":null,"abstract":"\u0000 Based on recent earthquakes experiences in Taiwan, losses do not necessarily result from damages of building structures but non-structural components. For instance, the leakage of the fire protection sprinkler systems in hospitals during small earthquakes could results in shortage of medical function and fire protection, and malfunction and repairs of medical equipment. The break of sprinkler systems caused by strong earthquakes could even harm the life safety. Taking a medium-scale hospital as an example, this research aims to conduct a simplified seismic evaluation method to improve seismic performance of the fire protection sprinkler system in critical buildings. The content of this research is summarized below:\u0000 1. Numerical analysis of the sample sprinkler piping system: a detailed numerical model of the fire protection sprinkler system in the sample hospital was established with SAP2000 v.20 software. Proper parameters to simulate the threaded joint of piping and the gap between adjacent partition walls or ceiling systems were proposed and verified by the results of component tests and shaking table tests. Ambient vibration tests in the sample hospital were conducted with velocimeters to clarify the structural characteristics of the building structure and the sprinkler piping system.\u0000 2. Fragility analysis of sprinkler piping systems: seismic fragility curves the fire protection sprinkler system in the sample hospital were conducted according to a mount of detailed analysis results and verified by the real damage state under Jiaxian earthquake. The effects of engineering demand parameters and categories of ground motion on fragility results are discussed for three types of failure modes.\u0000 3. Simplified seismic evaluation method for sprinkler piping systems: according to the results of shaking table tests and detailed analysis, a reliable simplified evaluation method was established to predict seismic behavior of typical sprinkler piping systems in hospitals by the information obtained from in-situ survey. The conservative level and accuracy of simplified evaluation results were verified by comparing the results of fragility analysis of numerical model and simplified evaluation.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128822546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research and Development of Viscous Fluid Dampers for Improvement of Seismic Resistance of Thermal Power Plants: Part 8 — Evaluation of Vibration Control Performance Using Experimental Design Method","authors":"K. Minagawa, K. Aida, Go Tanaka, S. Fujita","doi":"10.1115/pvp2019-93535","DOIUrl":"https://doi.org/10.1115/pvp2019-93535","url":null,"abstract":"\u0000 After Great East Japan Earthquake, coal-fired thermal power generation is a very important power source in Japan. In addition, Hokkaido Eastern Iburi Earthquake occurred in Japan in 2018, and damage of coal-fired thermal power plants by this earthquake caused blackout in very wide area. Therefore improvement of the seismic performance of the thermal power plants is a very important issue. In general boilers of coal-fired power plants are suspended from the upper end of support structures in order to allow thermal expansion of the boilers. Therefore boilers are structures that easily sway by earthquakes. In order to suppress the vibration, stoppers made of steel are generally installed between boilers and their support structures. Although stoppers made of steel can suppress the vibration effectively and economically, further improvement of seismic performance is required from the viewpoint of abovementioned issue. Therefore authors have proposed and developed a vibration control damper for coal-fired power plants instead of the stopper made of steel. Construction of the damper is similar to oil dampers, but inner fluid is viscous fluid. In PVP 2017, the basic performance of the proposed damper was presented. In PVP 2018, influence of dispersion of damper properties was also investigated. In addition, seismic response analyses using various earthquakes that include long period and long duration earthquake waves were carried out. As a result of previous investigations, it was confirmed that the proposed damper has good performance in its lifetime. However, parameters of dampers were selected manually. Therefore, influence of parameters of dampers on the vibration control performance were evaluated theoretically by using the experimental design method in this paper. The experimental design method is one of the effective techniques for research such as investigation of the influence of the habitat environment on the growth of crops. The selection of damper parameters is complex optimization, because so many variables need to be optimized. Therefore the experimental design method is suitable technique for the evaluation of damper parameters. This paper will evaluate vibration control performance from the viewpoint of the experimental design method.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115409175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast Reactor Core Seismic Analysis for Verification of Assessment Model Considering Deformation of Core Elements","authors":"Shinichiro Matsubara, Akihisa Iwasaki, K. Kawamura, Hidenori Harada, Tomohiko Yamamoto","doi":"10.1115/pvp2019-93778","DOIUrl":"https://doi.org/10.1115/pvp2019-93778","url":null,"abstract":"\u0000 To design fast reactor (FR) core components, seismic response must be evaluated in order to ensure structural integrity. Thus, a core seismic analysis method has been developed to evaluate 3D core vibration behavior considering fluid structure interaction and vertical displacements (rising). The analysis code is verified by a series of vibration tests.\u0000 The evaluation model to simulate the influence of core element deformation due to heat and irradiation were developed and the analysis of the seismic test was performed. And the evaluation model was verified by comparing the seismic test and analysis results.\u0000 A fast reactor core consists of hundreds of core elements, which lengthen due to thermal expansion and swelling. So, the core elements are self-standing on the core support structure and not restrained in the axial direction. When the vertical seismic excitation surpasses gravitational acceleration, it is necessary to consider vertical displacements and horizontal displacements of the core elements simultaneously. This 3-D vibration behavior is affected by the fluid loads from ambient coolant and the interference of surrounding structures. To solve this, the influential factors to vibration behaviors due to the structure and fluid body, including fluid structure interaction, are extracted and the 3-D reactor core group vibration analysis code (REVIAN-3D) is developed.\u0000 Core elements are deformed due to thermal expansion and irradiation, and are interfered with surrounding elements each other. The interference increases the frictional force acting on the core element and reduce the vertical displacement (rising) of the core element during the earthquake. To evaluate this reduction of rising, the evaluation model simulating this deformation is incorporated in REVIAN-3D.\u0000 In this study, the analysis of the vibration test was carried out using the new incorporated evaluation model. As the deformation of mock-up increases, the vertical displacement (rising) decreases, and when the initial interference due to deformation exceeds the threshold, no rising occurs. This trend agreed well between the vibration test and analysis. It is verified that the new incorporated evaluation model simulates the test result enough.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122567140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}