Volume 8: Seismic Engineering最新文献

{"title":"Sliding Response of Unanchored Steel Storage Tanks Subjected to Seismic Loading","authors":"Bledar Kalemi, M. Farhan, D. Corritore","doi":"10.1115/pvp2019-93310","DOIUrl":"https://doi.org/10.1115/pvp2019-93310","url":null,"abstract":"\u0000 Steel storage tanks are critical components of an industrial installation due to their high seismic vulnerability and containment of hazardous materials. Failure of a which, may lead to loss of containment (LOC) triggering domino effects such as explosion, environmental pollution, loss of functionality and disruption of business. Past earthquakes have demonstrated different type of failure modes in steel storage tanks. Although there are plenty of studies related to different failure modes like elephant foot buckling or tank uplifting, there are very few efforts on the sliding behavior of tank. Large displacements caused by the tank sliding can lead to pipe detachment and release of hazardous material which might cause damage propagation. Consequently, this damage state is very important for the Quantitative Seismic Risk Assessment of industrial plants.\u0000 In order to enumerate the sliding displacement of unanchored steel storage tanks, a simplified numerical model realized with OpenSees platform is proposed. The friction model used in OpenSees is calibrated with the results obtained from ABAQUS FE model. Sliding response of tanks with different D/H ratio is analyzed using the simplified model. Fragility curves for the tank sliding damage state are analytically evaluated for different D/H ratio of the tank using the “cloud method”. Finally, a parametric study is conducted in order to comprehend the influence of different parameters on the sliding behavior such as friction coefficient, tank filling level and the influence of the vertical component of ground motions.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"37 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":"114689787","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 Three-Dimensional Isolation System for Sodium-Cooled Fast Reactor: Part 4 — Proposal of Optimal Combination Method for Disc Spring Units and Newly Friction Model for Sliding Elements","authors":"Tsuyoshi Fukasawa, S. Okamura, T. Somaki, Takayuki Miyagawa, M. Uchita, Tomohiko Yamamoto, Tomoyoshi Watakabe, S. Fujita","doi":"10.1115/pvp2019-93480","DOIUrl":"https://doi.org/10.1115/pvp2019-93480","url":null,"abstract":"\u0000 The authors proposed a newly three-dimensional isolation system, consisting of a rubber bearing, vertical oil dampers and disc spring units, to reduce the seismic response in the vertical direction as well as horizontal direction. This isolation system is employed with a number of disc spring units to provide the vertical restoring force to the superstructure. The disc spring units are combined by three disc springs in parallels and they are are stacked in six serials. The vertical restoring force has susceptible to the variation forces for the individual disc springs because the disc spring units are combined in the six serials. The The purpose of this paper is to present two kinds of proposal to improve the quality control of our isolation system and the prediction accuracy of seismic response. The first is to create the the optimal combination method for the disc spring units using the meta-heuristic algorithm to minimize the variation of vertical vertical restoring force. The proposed optimal method was verified through the result of static loading tests using the 72 disc springs which have the half dimensions to full scale. The second is to create a newly analytical model for the friction force caused by polymeric materials. The proposed analytical model was verified by comparing the loading test results. Moreover, the seismic isolation performances were clarified by the seismic response analysis that consider the vertical restoring force of the disc spring units which were combined using the optimal method and the friction force of sliding elements which were modeled by the proposed friction model. This analytical result revealed that our isolation system can reduce the seismic response not only for the high frequency components but also the low frequency ones.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"9 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":"130262677","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":"Study on Seismic Designs Controlling Locations of Failure Inside Steel Frame Structures Under Severe Ground Motions","authors":"Kensuke Shiomi","doi":"10.1115/pvp2019-93629","DOIUrl":"https://doi.org/10.1115/pvp2019-93629","url":null,"abstract":"\u0000 For steel frame infrastructure facilities like thermal power plants, storage facilities or port facilities, the more advanced seismic performance is needed which not only prevent major damages against assumed design ground motions but also result in the “desirable failure mode” that concerns the recovery works or prevent from resulting in catastrophic failure mode, even under severe ground motions beyond design assumptions in which occurrence of some damages in structures are inevitable.\u0000 “Seismic structures which can control the locations of failure of structural members inside structures” is one of the examples of this seismic performance. By adding this performance to steel frame structures at the stage of seismic design, the high resilience structures which concern recovery works after earthquakes can be realized.\u0000 In this research, a basic study on the seismic performance which controls the locations of fractures of steel frame members by adjusting the cross sections of each structural member was carried out. The analytical studies about the design procedure to realize this seismic performance were conducted. Then, by conducting the shaking table tests for simple steel frame structures and confirming the location of fractures under dynamic loads, the possibility of this seismic performance was discussed experimentally.","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":"133507906","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":"Development of Active Vibration Damping Device Adjusting TMD to Various Periodic Bands of Seismic Waves","authors":"Kota Watanabe, N. Miura, A. Sone","doi":"10.1115/pvp2019-93780","DOIUrl":"https://doi.org/10.1115/pvp2019-93780","url":null,"abstract":"\u0000 There are many high-rise buildings all over the world, especially urban areas. Their usage is diverse, such as offices and residences. Therefore, earthquake countermeasures for high-rise buildings are indispensable. It is known that a tuned mass damper (TMD), which is mainly installed for countermeasures against wind shaking, does not show sufficient damping effect when large earthquake occurs or when higher modes vibration is excited. In addition, when exceeding the drive limit of the TMD in resonance, the TMD may collide against the stopper and deteriorate the response of the building. There are some researches targeting building with TMD, and many of them aim at developing new devices. However, installing a new equipment instead of TMD requires a lot of cost and construction period. Therefore, in this research, an active device that can be attached to TMD is developed. Moreover, validity is examined by numerical simulation. In this paper, parameters of the passive elements are verified as a basic research of the proposed device.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"543 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":"116879160","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":"Mitigation of Rocking and Sliding Motion of a Free-Standing Structure Subjected to Base Excitation Using Coaxial Circular Cylinders Containing Highly Viscous Liquid in Annular Spaces","authors":"A. Shintani, Tomohiro Ito, C. Nakagawa","doi":"10.1115/pvp2019-93205","DOIUrl":"https://doi.org/10.1115/pvp2019-93205","url":null,"abstract":"\u0000 In this study, the effectiveness of coaxial circular cylinders containing a highly viscous liquid in annular spaces for reduction of rocking motion of a free-standing structure is investigated both analytically and experimentally. First, an analytical model of coupled rocking and sliding motions of a free-standing structure, including the coaxial circular cylinders, subjected to seismic input was derived. The free-standing structure was modeled as a free-standing rigid body. The cylinders were attached to the bottom of the rigid body as a damping device.\u0000 We then experimentally derived the friction coefficients, inertia moments, and a damping coefficient in the rotating direction.\u0000 Furthermore, using these parameters, the effectiveness of this system in suppressing the rocking motion is investigated analytically. The proposed method was determined to be very effective in suppressing the rocking motion of a rigid body subjected to a seismic input by the experiment.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"10 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":"124739975","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":"Selection of the Test Specimens for Seismic Tests of Air-Operated Valve Actuators for Nuclear Power Plants","authors":"N. Kojima, Y. Tsutsumi, Yoshinao Matsubara, K. Nishino, Yasuyuki Ito, R. Kubota, S. Suzuki","doi":"10.1115/pvp2019-93168","DOIUrl":"https://doi.org/10.1115/pvp2019-93168","url":null,"abstract":"\u0000 The soundness for the function of air-operated valves in nuclear power plants during earthquake has been investigated via seismic test results and so forth. Since the seismic response acceleration has increased more and more with a recent reassessment of design earthquake ground motions conducted according to the revised Japanese nuclear safety regulation, it is necessary to evaluate the soundness for the function of various valves subject to large acceleration beyond design basis. The air-operated valves currently installed in the nuclear power plants in Japan play the important roles in the sever accident events. In this study, we classified them based on the valve type, manufactures and the previous test results. Furthermore, we proposed the strategy for evaluating the seismic-proof and the seismic test condition for examining the soundness of the dynamic function. Here, the dynamic function is defined as the function required under and after earthquakes.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"118 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":"121447015","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":"Leakage of a High Temperature and High Pressure Flange Metal Gasket due to its Ratcheting in Alternating Pours of Rain","authors":"Yanan Chen, Jianbo Wang, Chu-lin Yu, Bingjun Gao","doi":"10.1115/pvp2019-93193","DOIUrl":"https://doi.org/10.1115/pvp2019-93193","url":null,"abstract":"\u0000 In the high pressure ethylene polymerization process, pipes transmitting reaction product are often bolt-flange connected with metal gaskets which demands high tightness. However ethylene and polyethylene was found leaking from a flange connection in the pipe out of a polymerization kettle after several pours of rain, which leads to an emergency shutdown. A finite element model was worked out to simulate the ratcheting of the metal gasket during the on and off rains by keeping the temperature of the pipe, flange, and gasket as 270°C, but changing the temperature of bolts from higher temperature 270°C to a lower temperature cyclically. Elastic and perfect plastic model was conservatively employed in the ratcheting analysis. It is found that gasket plastic strains accumulate with the bolt temperature drop cycles. The higher the bolt temperature drop, the more plastic strain accumulation. Consequently, the contact pressure between the flange and the gasket reduces with the bolt temperature cycles. The higher the temperature drop, the less the flange connection tightness. It reveals that bolt temperature drop below 155°C does not destroy the flange connection tightness with a gasket parameter 3.0. When temperature drops are above 155°C, temperature cycles to destroy the flange connection tightness decrease with temperature drops, namely the higher the temperature drop, the less temperature cycles needed to destroy the flange connection tightness. A margin line has been worked out to correlate the bolt temperature drops and cycles to the gasket leakage.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"8 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":"115856176","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 7 — Evaluation of Lifetime Using Experimental Design Method","authors":"K. Aida, K. Minagawa, Go Tanaka, S. Fujita","doi":"10.1115/pvp2019-93534","DOIUrl":"https://doi.org/10.1115/pvp2019-93534","url":null,"abstract":"\u0000 In 2011, Great East Japan Earthquake that was the largest earthquake in Japanese history occurred. The earthquake had large acceleration, long duration and a lot of aftershocks, and coal-fired thermal power plants were damaged by the earthquake. Boiler structures in coal-fired thermal power plants are generally high-rise structures, and boilers are simply suspended from the top of the support structures in order not to restrict thermal expansion. Therefore boilers are easy to vibrate. In order to suppress vibration of boilers during earthquakes, stoppers are generally set between boilers and support structures. The stoppers are made of steel, and dissipate vibration energy by plastic deformation. However aseismic requirements for thermal power plants have been increased as a result of the Great East Japan Earthquake. Thus authors have developed a vibration control damper for coal-fired power plants. The damper is set instead of conventional stopper. 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 lifetime 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 evaluates lifetime of dampers from the viewpoint of the experimental design method.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"1 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":"131127365","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":"Failure Modes of Piping Systems Under Seismic Loading and Evaluation","authors":"Satoru Kai, Akihito Otani","doi":"10.1115/pvp2019-93438","DOIUrl":"https://doi.org/10.1115/pvp2019-93438","url":null,"abstract":"Failure modes of piping systems under seismic motions were discussed for several decades if the fatigue failure is dominant or there is some possibility that the plastic collapse could occur. A handful of ratchet-buckling failure observed in Pipe Fittings Dynamic Reliability Program by EPRI was frequently taken up as the evidence of the plastic collapse, and inclusion of seismic response on structures into the Primary stress evaluation for piping systems in the code evaluation was considered to be conventionally justified. Although prevention of the plastic collapse type failure is the purpose of imposing the Primary stress evaluation, the other experimental tests conducted in several countries for decades were unable to represent the plastic collapse of piping components exposed to seismic loading and the discussion was abandoned for a while. However, the drastically increased design seismic motions for nuclear power plants due to several huge earthquake occurred in Japan reminded us of exploring the fact of the plastic collapse and the necessity of the Primary stress evaluation. The load classification concept proposed by the authors introduces 3 conceptual force terms from the equation of motion to clarify the seismic loading from the aspect of the correlation of the said force terms. Based on the finding from the concept that the input force amplitude is to be evaluated for Primary stress, the gross-plastic deformation on a single cantilever with elastic-plastic analyses using multiple of single-cycle sinusoidal forcing functions was compared with the input force term. When the plastic collapse is defined as a gross-plastic deformation, the level of plastic collapse was found to be possibly anticipated with a static force evaluation that can be substitute for the conventional Primary stress evaluation with the dynamic response analysis.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"22 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":"133420635","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":"Resource Allocation Model Toward Seismic Water Pipeline Risk Mitigation Measures","authors":"E. Peyghaleh, T. Alkhrdaji","doi":"10.1115/pvp2019-93057","DOIUrl":"https://doi.org/10.1115/pvp2019-93057","url":null,"abstract":"\u0000 History of earthquake’s damages have illustrated the high vulnerability and risks associated with failure of water transfer and distribution systems. Adequate mitigation plans to reduce such seismic risks are required for sustainable development. The first step in developing a mitigation plan is prioritizing the limited available budget to address the most critical mitigation measures. This paper presents an optimization model that can be utilized for financial resource allocation towards earthquake risk mitigation measures for water pipelines. It presents a framework that can be used by decision-makers (authorities, stockholders, owners and contractors) to structure budget allocation strategy for seismic risk mitigation measures such as repair, retrofit, and/or replacement of steel and concrete pipelines. A stochastic model is presented to establish optimal mitigation measures based on minimizing repair and retrofit costs, post-earthquake replacement costs, and especially earthquake-induced large losses. To consider the earthquake induced loss on pipelines, the indirect loss due to water shortage and business interruption in the industries which needs water is also considered. The model is applied to a pilot area to demonstrate the practical application aspects of the proposed model. Pipeline exposure database, built environment occupancy type, pipeline vulnerability functions, and regional seismic hazard characteristics are used to calculate a probabilistic seismic risk for the pilot area. The Global Earthquake Model’s (GEM) OpenQuake software is used to run various seismic risk analysis. Event-based seismic hazard and risk analyses are used to develop the hazard curves and maps in terms of peak ground velocity (PGV) for the study area. The results of this study show the variation of seismic losses and mitigation costs for pipelines located within the study area based on their location and the types of repair. Performing seismic risk analysis analyses using the proposed model provides a valuable tool for determining the risk associated with a network of pipelines in a region, and the costs of repair based on acceptable risk level. It can be used for decision making and to establish type and budgets for most critical repairs for a specific region.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"32 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":"134118822","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}