Volume 8: Seismic Engineering最新文献

{"title":"Ultimate Limit States of Piping Supports With Outer Diagonal Brace Under High Acceleration Sinusoidal Shaking Condition","authors":"Ryuya Shimazu, M. Sakai","doi":"10.1115/PVP2018-84937","DOIUrl":"https://doi.org/10.1115/PVP2018-84937","url":null,"abstract":"In this study, the fundamental mechanical inelastic behavior of piping supports was investigated in order to consider an effective elastic-plastic evaluation method. High-acceleration vibration tests were conducted using the resonance shaking table installed in Central Research Institute of Electric Power Industry (CRIEPI), and the ultimate limit states of piping supports under vibration conditions were observed. Each specimen had an outer diagonal brace. Buckling or fatigue failure occurred in the vibration test. Fatigue failure did not occur in the static load test. The static and dynamic skeleton curves were in agreement with each other when the failure mode was the same. When the response load did not reach the buckling load in the vibration test, fatigue cracks occurred after the stable response. The locations of the fatigue cracks tended to be where the local buckling occurred in the static tests. In both the vibration and the static load tests, even if the load decreased after the maximum load by buckling, the reaction force of approximately one third of the maximum load was seen, and the reaction force did not become 0 kN.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"30 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114103293","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 Resonating Lattice TMD to Reduce Pipeline Vibrations","authors":"Mahesh Murugan Jaya, R. Ceravolo, E. Matta, L. Z. Fragonara","doi":"10.1115/PVP2018-84377","DOIUrl":"https://doi.org/10.1115/PVP2018-84377","url":null,"abstract":"There are numerous ways to realize vibration absorbers. In this study, a new method is proposed wherein an elastomeric lattice is used. The geometrical configuration of the lattice is designed such that it transfers energy from the main system and is dissipated by the inherent material damping of the lattice material. The applicability of this system is numerically evaluated for pipelines by using two simple lattices whose geometries were optimized and the performances under harmonic loads compared with that of the theoretical optimal TMD. Eventhough they were capable of reducing the vibrations significantly, it was found to be less efficient at small mass ratios while at large mass ratios, the lattices performed similar to the theoretical optimal TMD. Nevertheless, in order to use such systems for pipelines or pipeline like structures such as chimneys, further studies are required using improved lattice configurations that can work efficiently for the whole range of mass ratios.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116166309","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":"Evaluating Large Aboveground Storage Tanks Subject to Seismic Loading: Part I — Closed-Form Solutions and Equivalent Static Analysis","authors":"P. E. Prueter, S. R. Kummari","doi":"10.1115/PVP2018-84836","DOIUrl":"https://doi.org/10.1115/PVP2018-84836","url":null,"abstract":"Evaluating the dynamic response of large, aboveground storage tanks exposed to seismic loading is multifaceted. There are foundation-structure and fluid-structure interaction effects that can influence the overall tank behavior and likely failure modes. Additionally, local stresses at anchor bolt support chair attachments and the shell-to-floor junction can be difficult to quantify without detailed finite element analysis (FEA). Often times, performing explicit dynamic analysis with liquid sloshing effects can be time consuming, expensive, and even impractical. The intent of this paper is to summarize simplified analysis techniques that can be leveraged to evaluate aboveground storage tanks subject to seismic loading.\u0000 Closed-form calculations to establish a recommended design for a tank, including seismic considerations, are available in storage tank design standards, including API 650 [1] (Appendix E). Seismic design standards have evolved significantly in recent years. Furthermore, for many vintage, in-service storage tanks, explicit seismic considerations were not incorporated into the original design. In Part I of this study, these design equations and other closed-form solutions are used to evaluate the structural integrity of a large, in-service, mechanically-anchored storage tank. The design equations in API 650 [1] are used to form the basis of simplified, equivalent static analysis, where seismic loads are applied to a three-dimensional FEA model via equivalent lateral body forces. These practical results are then compared to explicit dynamic seismic behavior of the same tank with fluid-structure interaction effects considered (in Part II of this study [2]). These comparisons offer insight into the appropriateness of using simplified hand-calculations and equivalent static analysis (and their relative conservatism) in lieu of more rigorous explicit dynamic and fluid sloshing simulations.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121544452","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":"Enhanced Seismic Fragility Analysis of Unanchored Above-Ground Steel Liquid Storage Tanks","authors":"H. Phan, F. Paolacci, S. Alessandri, P. Hoang","doi":"10.1115/PVP2018-84367","DOIUrl":"https://doi.org/10.1115/PVP2018-84367","url":null,"abstract":"Earthquake damage in recent decades has revealed that storage tanks are one of the most vulnerable components in petrochemical and oil processing plants. Damage to tanks commonly associated with losses of containment, and thus results in the overall damage to nearby areas. Many of existing steel storage tanks were designed with outdated analysis methods and with underestimated seismic loads; therefore, various types of failure may occur during a strong ground shaking. This paper aims to present an appropriate methodology for the component fragility evaluation of existing storage tanks in a process plant, which will support for the determination of the loss of containment in terms of the ground motion intensity measure and finally the quantitative risk analysis of the plant and its nearby areas. In this respect, an unanchored oil storage tank, which is ideally located in Sicily (Italy), is selected as a case study. The significance of modeling parameters of the tank is first investigated with a screening study, which is based on nonlinear static pushover analyses of the tank using the ABAQUS software. The study aims to enhance the understanding of which modeling parameters significantly affect the seismic response of the tank and to reduce the number of analyses in the fragility evaluation. The fragility curves are then developed based on a lumped-mass model that is calibrated from the static pushover analysis results. Sources of uncertainty, related to significant parameters previously identified, are considered in the fragility analysis using a sampling procedure to generate statistically significant samples of the model.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133996911","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 Behaviour of Torsionally Coupled Structures Equipped With Viscoelastic Dampers","authors":"F. Paolacci, M. Ciucci","doi":"10.1115/PVP2018-84373","DOIUrl":"https://doi.org/10.1115/PVP2018-84373","url":null,"abstract":"The paper deals with the seismic passive control of torsionally coupled structures, equipped with viscoelastic dampers. Based on the dynamic response of a three degrees of freedom model to a white noise input process, an energy-based design procedure is proposed, and its effectiveness is investigated through an extensive parametric analysis. Subsequently, the proposed methodology is applied to a seven-story torsionally coupled building.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133125939","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":"The Simulation of Strong Ground Motion Using Empirical Green Function and Stochastic Method for Southern Taiwan Area","authors":"T. Teng, P. Chen, Ting-Wei Chang, Yuan-Sen Yang, C. Chiu, W. Liao","doi":"10.1115/PVP2018-84670","DOIUrl":"https://doi.org/10.1115/PVP2018-84670","url":null,"abstract":"This study presents strong ground motion simulation methods for the future fragility study of a power plant in Southern Taiwan. The modified stochastic method and empirical Green function method are utilized to synthesize the strong ground motions of specific events. A modified physical random function model of strong ground motions for specific sites and events is presented in this study with verification of sample level. Based on the special models of the source, path, and local site, the random variables of the physical random function of strong ground motions is obtained. The inverse Fourier transform is used to simulate strong ground motions. For the empirical Green function method, the observed site records from small earthquake events occurring around the source area of a large earthquake are collected to simulate the broadband strong ground motion from a large earthquake event. Finally, an application of proposed two simulated methods of this study for simulating the ground motion records of Nishi-Akashi Station at 1995 Kobe earthquake and 2006 Southern Taiwan PingDong earthquake are presented.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133688658","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":"Evaluating Large Aboveground Storage Tanks Subject to Seismic Loading: Part II — Explicit Dynamic Analysis With Liquid Sloshing Effects","authors":"S. R. Kummari, P. E. Prueter, M. Bifano","doi":"10.1115/PVP2018-84837","DOIUrl":"https://doi.org/10.1115/PVP2018-84837","url":null,"abstract":"The dynamic response of storage tanks subjected to seismic loading is complex. Analyzing the structural response of a tank is not only dependent on accurately modeling the major design features and simulating the seismic loading, but also the sloshing of the fluid contained within the tank can affect the overall behavior and likely failure modes. Advanced dynamic simulation techniques, such as the ones discussed herein, permit comparison between these closed-form methods and computational predictions; that is, any potential conservatism or lack thereof associated with traditional design by rule methodologies can be identified using computational analysis. Additionally, for tanks that were not originally designed to a modern Code or recommended practice that includes consideration for seismic loading, the computational analysis methods discussed in this study offer a means to evaluate the structural integrity of vintage tanks under seismic loading conditions that are still in service today.\u0000 This paper discusses explicit dynamic finite element analysis (FEA) techniques to simulate seismic loading on a large, aboveground, in-service Ammonia storage tank that carries a high consequence of failure. The fluid-structure interaction and sloshing behavior of the contained fluid are directly accounted for. Commentary on using smooth particle hydrodynamics (SPH), coupled Eulerian-Lagrangian (CEL), and computational fluid dynamics (CFD) analysis techniques is provided. The underlying methodology behind these simulation techniques is discussed, and the overall dynamic response of the tank is investigated. The results from the explicit dynamic seismic simulations are compared with the current seismic design guidance provided in API 650 [1] and equivalent static simulation techniques (documented in Part I of this study [2]). Furthermore, this case study highlights a practical application where advanced analysis is employed to investigate a real-life fluid-structure interaction problem.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125525041","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 the Simplified Analysis and Relevant Calculations to Evaluating Uplift Displacement of Unanchored Tanks","authors":"T. Taniguchi, Y. Yoshida, K. Hatayama","doi":"10.1115/PVP2018-84239","DOIUrl":"https://doi.org/10.1115/PVP2018-84239","url":null,"abstract":"Evaluation of the rocking motion of unanchored cylindrical tanks subjected to the ground acceleration is a main topic in the framework of the seismic vulnerability assessment of this particular kind of structures. However, despite the anchored or unanchored tanks, any calculation that attempts fully evaluate tank uplift has not been presented, while many of the analyses of the tank rocking motion and the deformation of the tank bottom plate have been respectively presented. This paper carries out a thought experiment of applicability of these analyses to evaluating uplift of the unanchored tanks. First, this paper focuses on an anchored tank at a chemical plant whose anchor bolts were pulled-out during the 2011 off the pacific coast of Tohoku Earthquake. Second, combine a few analyses of uplift of the unanchored tanks being available to date; then, calculate the uplift displacement of an anchored tank of interest as if it were an unanchored tank. Next, infer the pulling-out length of anchor bolt of the anchored tank of interest from a photo in a reconnaissance report; then, compare it with the uplift displacement calculated. Since the uplift displacement calculated is larger than that inferred. Since a discrepancy between them would be responsible for the constraint effects of anchors that have not been clearly quantified, the present analyses of the tank rocking motion and the deformation of the tank bottom plate may have a potential to give an appropriate uplift of unanchored tanks.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"228 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120878938","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":"On Categorization of Seismic Load As Primary or Secondary for Piping Systems With Hardening Capacity","authors":"P. Labbé","doi":"10.1115/PVP2018-84608","DOIUrl":"https://doi.org/10.1115/PVP2018-84608","url":null,"abstract":"The concept of primary/secondary categorization is first reviewed and generalized for its application to a non-linear oscillator subjected to a seismic load. Categorizing the seismic load requires calculating the input level associated with the oscillator ultimate capacity and comparing it to the level associated with the plastic yield. To resolve this problem, it is assumed that the non-linear oscillator behaves like a linear equivalent oscillator, with an effective stiffness (or frequency) and an effective damping. However, as it is not a priori possible to predict the equivalent stiffness and damping, a wide range of possibilities is systematically considered. The input motion is represented by its conventional response spectrum.\u0000 It turns out that key parameters for categorization are i) the “effective stiffness factor” (varying from 0 for perfect damage behaviour to 1 for elastic-perfectly plastic) and the slope of the response spectrum in the vicinity of the natural frequency of the oscillator. Effective damping and spectrum sensitivity to damping play a second order role. A formula is presented that enables the calculation of the primary part of a seismically induced stress as a function of both the oscillator and input spectrum features. The formula is also presented in the form of a diagram.\u0000 This paper follows-up on a similar paper presented by the author at the PVP 2017 Conference [1]. The new development introduced here is that the oscillator exhibits hardening capacity, while no hardening was assumed in [1]. It appears that the conclusions are slightly modified but the trend is very similar to the non-hardening case.\u0000 Regarding piping systems, it appears that even when experiencing large plastic strains under beyond design input motions, their observed effective frequency is very close to their natural frequency, decreasing only by a few percents (experimental data from USA, Japan and India are processed). These observations lead to the conclusion that the seismic load, or the seismically induced inertial seismic strains, should basically be regarded as secondary.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132899488","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":"Dynamic Analysis and Design Methods for Combustion Turbine Exhaust Silencers Employing Acoustical Baffles","authors":"A. Gjinolli, Jason E. Dorgan, Elden F. Ray","doi":"10.1115/PVP2018-84160","DOIUrl":"https://doi.org/10.1115/PVP2018-84160","url":null,"abstract":"Combustion turbines are frequently used because they provide the most power in the smallest footprint and their modular design makes them an economical choice. These machines are used across all land-based industries as well as marine applications. The exhaust system must perform its basic function of conducting exhaust gases, which can be as high as 1250° F (675° C), safely away from the adjacent equipment and workers, and mitigate the exhaust noise under a wide range of requirements and conditions. In addition, new requirements limit shell temperatures and exhaust leakage to prevent fire or explosion of fuel gas that may leak from equipment (ATEX).\u0000 This paper presents a review of the analytical processes used in the development of a silencer system to achieve optimal performance metrics. These systems are typically comprised of parallel baffles for a wide range of conditions including aero-acoustical performance, system pressure and high flow rates, thermal stresses, environmental conditions (ocean, seismic and wind), flow-induced vibration, corrosion, and fatigue – design life analysis. The specific requirements of the baffle design will be discussed through a specific case study relative to typical rectilinear (parallel) baffles used in many installations, including land-based power generation plants (Figure 1), and offshore platforms (Figure 2).\u0000 This paper will discuss the analytical methods used to address these challenges via a case study. A combination of static, vibration-pulsation and dynamic structural analysis with specific attention to the seismic analysis of the parallel baffles used in skirt and structural steel supported vessels, as well as acoustical design and flow modeling techniques are used to evaluate the design options.","PeriodicalId":180537,"journal":{"name":"Volume 8: Seismic Engineering","volume":"516 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133339235","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}