Author: Aikaterini Mousteraki
Publisher:
ISBN:
Category :
Languages : en
Pages :
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Book Description
"Seismic isolation is an effective system to protect structural and non-structural components of high-importance structures, such as hospitals, that need to remain functional in the aftermath of earthquakes. Under extreme earthquakes though, the design displacement of the isolation systems might be exceeded; hence impacts against surrounding moat walls and/or adjacent buildings could be generated. During recent earthquakes, pounding phenomena have caused structural damage or even collapse of civil infrastructure.This thesis evaluates the performance of a nine-storey, steel moment resisting frame (MRF) hospital, which is retrofitted by means of seismic isolation. Triple Pendulum Bearings are employed including the potential for poundings. The hospital is a 1960s Type 2 Construction; thus, it has been characterized as the Canadian Seismic Research Network (CSRN) Benchmark Steel MRF Hospital Structure. The base-isolated building is subjected to a set of 40 ground motions that are selected to represent the seismic hazard in a high-seismicity region in Vancouver. The retrofitted configuration is modeled on an open source nonlinear building simulation platform. The numerical modeling and the impact modeling approach are both validated through the comparison with prior numerical and experimental results. This thesis is concerned with the amplification on the superstructure's dynamic response with the presence of poundings, which implies a potential reduction of the effectiveness of the implemented seismic retrofit system. Highly increased acceleration values that affect the building's non-structural components are recorded through nonlinear response history analyses. It is concluded that the selection of the available gap displacement between the hospital under concern and the surrounding moat walls, should take into consideration two parameters; the design displacement of the isolators and the displacement generated from the nonlinear response history analyses that minimizes pounding effects. A gap displacement between the building and the surrounding moat walls is recommended for limiting impact phenomena. This thesis provides valuable insights into the increase of the effectiveness and reliability of isolation systems in Canada during strong earthquake motions, when poundings are present." --
Author: Alireza Sarebanha
Publisher:
ISBN:
Category :
Languages : en
Pages : 241
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Book Description
Seismic isolation can be an effective strategy to protect critical facilities including Nuclear Power Plants (NPPs) from the damaging effects of horizontal earthquake ground shaking. For critical facilities, the isolation system should demonstrate a high-confidence of low-probability of failure at the design level and the load carrying capacities should be maintained under beyond design earthquake shaking (BDBE). Experimental evaluation of seismic isolation bearings is important to fully understand their behavior and capacity for reliable performance. Safety mechanisms such as a stop can be imposed to prevent excessive displacement of the isolation system under BDBE, however, this raises concerns for detrimental effects of pounding against a stop or moat wall. Methods of analysis are presented in this dissertation to evaluate both seismic isolation system behavior under extreme earthquakes and the potential effects of pounding by imposing displacement restraints. The dynamic response of an isolated NPP depends on the combined characteristics of the ground motion, bearings, and structure while the seismic isolation bearings themselves can exhibit complex nonlinear behavior that depends on several factors, including the scale size, axial load, temperature, and rate of loading especially under strong earthquake shaking. With a specific interest on the in-structure response of seismically isolated NPPs, hybrid simulation is shown to be a viable approach to examine bearing behavior at full scale under realistic earthquake loading. The adaptation of a full-scale bearing test machine (SRMD testing facility at UC San Diego) and developed toolsets for the implementation of fast hybrid simulation to study the dynamic response of base isolated NPP using full scale lead plug rubber bearings under realistic earthquake loading conditions are presented. Results from these tests validate the effectiveness of seismic isolation technology for application in nuclear facilities and provide valuable data towards improving numerical models of seismic isolation bearings. In a seismically isolated NPP, a surrounding moat wall can function as a stop to limit isolation system displacements and prevent bearing failure for beyond design basis shaking. Impact of isolated structures against a moat wall is of concern due to potential amplification of superstructure response. A moat wall model able to capture impact forces is proposed and used in numerical simulations to capture the effects of impact on the response of seismically isolated NPPs. Variable clearance to the stop and a range of properties for the impact model, moat wall and isolation system are considered to identify parameters that influence the response. Results indicate that large NPP plants as considered here can have significant penetration into the moat wall, not fully limiting displacements in the isolation system, while causing considerable increases in accelerations throughout the NPP. A simplified methodology to estimate impact response parameters including penetration is proposed towards developing design tools that consider these effects.
Author: Sarah L. Billington
Publisher:
ISBN:
Category :
Languages : en
Pages : 210
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Book Description
Author: Assembly of Mathematical and Physical Sciences (U.S.). Panel on Earthquake Problems Related to the Siting of Critical Facilities
Publisher:
ISBN:
Category : Earthquake engineering
Languages : en
Pages : 72
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Book Description
Author: Robert Jankowski
Publisher: Springer
ISBN: 3319163248
Category : Science
Languages : en
Pages : 168
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Book Description
This books analyzes different approaches to modeling earthquake-induced structural pounding and shows the results of the studies on collisions between buildings and between bridge segments during ground motions. Aspects related to the mitigation of pounding effects as well as the design of structures prone to pounding are also discussed. Earthquake-induced structural pounding between insufficiently separated buildings, and between bridge segments, has been repeatedly observed during ground motions. The reports after earthquakes indicate that it may result in limited local damage in the case of moderate seismic events, or in considerable destruction or even the collapse of colliding structures during severe ground motions. Pounding in buildings is usually caused by the differences in dynamic properties between structures, which make them vibrate out-of-phase under seismic excitation. In contrast, in the case of longer bridge structures, it is more often the seismic wave propagation effect that induces collisions between superstructure segments during earthquakes.
Author:
Publisher: AASHTO
ISBN: 1560514566
Category : Technology & Engineering
Languages : en
Pages : 63
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Book Description
This edition is based on the work of NCHRP project 20-7, task 262 and updates the 2nd (1999) edition -- P. ix.
Author:
Publisher: Government Printing Office
ISBN: 9780160926754
Category : Science
Languages : en
Pages : 206
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Book Description
The Rapid Visual Screening (RVS) handbook can be used by trained personnel to identify, inventory, and screen buildings that are potentially seismically vulnerable. The RVS procedure comprises a method and several forms that help users to quickly identify, inventory, and score buildings according to their risk of collapse if hit by major earthquakes. The RVS handbook describes how to identify the structural type and key weakness characteristics, how to complete the screening forms, and how to manage a successful RVS program.
Author:
Publisher:
ISBN:
Category : Earthquake resistant design
Languages : en
Pages : 400
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Book Description
Author: Federal Emergency Management Agency
Publisher: www.Militarybookshop.CompanyUK
ISBN: 9781782661535
Category : Science
Languages : en
Pages : 392
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Book Description
This full color manual is intended to explain the principles of seismic design for those without a technical background in engineering and seismology. The primary intended audience is that of architects, and includes practicing architects, architectural students and faculty in architectural schools who teach structures and seismic design. For this reason the text and graphics are focused on those aspects of seismic design that are important for the architect to know.
Author: Plevris, Vagelis
Publisher: IGI Global
ISBN: 1522520902
Category : Technology & Engineering
Languages : en
Pages : 338
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Book Description
Solid design and craftsmanship are a necessity for structures and infrastructures that must stand up to natural disasters on a regular basis. Continuous research developments in the engineering field are imperative for sustaining buildings against the threat of earthquakes and other natural disasters. Performance-Based Seismic Design of Concrete Structures and Infrastructures is an informative reference source on all the latest trends and emerging data associated with structural design. Highlighting key topics such as seismic assessments, shear wall structures, and infrastructure resilience, this is an ideal resource for all academicians, students, professionals, and researchers that are seeking new knowledge on the best methods and techniques for designing solid structural designs.
