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Description: This paper describes the approach taken by two Fluor Hanford projects for implementing of the seismic design criteria from DOE-STD-1189-2008, Appendix A. The existing seismic design criteria and the new seismic design criteria is described, and an assessment of the primary differences provided. The gaps within the new system of seismic design criteria, which necessitate conduct of portions of work to the existing technical standards pending availability of applicable industry standards, is discussed. Two Hanford Site projects currently in the Control Decision (CD)-1 phase of design have developed an approach to implementation of the new criteria. Calculations have been performed to determine the seismic design category for one project, based on information available in early CD-1. The potential effects of DOE-STD-1189-2008, Appendix A seismic design criteria on the process of project alternatives analysis is discussed. Present of this work is expected to benefit others in the DOE Complex that may be implementing DOE-STD-1189-2008.
Date: May 14, 2008
Creator: SK, OMBERG
Partner: UNT Libraries Government Documents Department

Application of bounding spectra to seismic design of piping based on the performance of above ground piping in power plants subjected to strong motion earthquakes

Description: This report extends the potential application of Bounding Spectra evaluation procedures, developed as part of the A-46 Unresolved Safety Issue applicable to seismic verification of in-situ electrical and mechanical equipment, to in-situ safety related piping in nuclear power plants. The report presents a summary of earthquake experience data which define the behavior of typical U.S. power plant piping subject to strong motion earthquakes. The report defines those piping system caveats which would assure the seismic adequacy of the piping systems which meet those caveats and whose seismic demand are within the bounding spectra input. Based on the observed behavior of piping in strong motion earthquakes, the report describes the capabilities of the piping system to carry seismic loads as a function of the type of connection (i.e. threaded versus welded). This report also discusses in some detail the basic causes and mechanisms for earthquake damages and failures to power plant piping systems.
Date: February 1, 1995
Creator: Stevenson, J.D.
Partner: UNT Libraries Government Documents Department

A report on the seismic capacity of the General Laboratory and Administration Building at Los Alamos National Laboratory

Description: A seismic analysis of the General Laboratory and Administration Building at Los Alamos National Laboratory is performed. The analyses are performed in detail for one portion of the building and then qualitatively extrapolated to other portions of the building. Seismic capacities are evaluated based on two sets of acceptance criteria. The first is based on Code-type criteria and is associated with a low probability of failure. This capacity is found to be in the 0.04--0.06 G ZPA range (the free field seismic motion is defined with a NUREG 0098 response spectrum). The second capacity is based on much less conservative criteria such as might be associated with a high probability of failure. This capacity is found to be about 0.15 G. Finally structural modifications are proposed that would increase the low probability of failure capacity to 0.15 G ZPA. These modifications consist of steel double angle braces or concrete shear walls placed at some of the frames in the building.
Date: January 1, 1995
Creator: Miller, C.A.; Costantino, C.J.; Zhu, Y.; Wang, Y.K.; Shteyngart, S.; Xu, J. et al.
Partner: UNT Libraries Government Documents Department

Development and implementation of seismic design and evaluation criteria for NIF

Description: The National Ignition Facility (NIF) is being built at the Lawrence Livermore National Laboratory (LLNL) as an international research center for inertial confinement fusion (ICF). This paper will provide an overview of NIF, review NIF seismic criteria, and briefly discuss seismic analyses of NIF optical support structures that have been performed by LLNL and the Ralph M. Parsons Company, the Architect and Engineer (A&E) for NIF. The NIF seismic design and evaluation criteria is based on provisions in DOE Standard 1020 (DOE-STD-1020), the Uniform Building Code (UBC), and the LLNL Mechanical Engineering Design Safety Standards (MEDSS). Different levels of seismic requirements apply to NIF structures, systems, and components (SSCs) based on their function. The highest level of requirements are defined for optical support structures and SSCs which could influence the performance of optical support structures, while the minimum level of requirements are Performance Category 2 (PC2) requirements in DOE-STD-1020. To demonstrate that the NIF seismic criteria is satisfied, structural analyses have been performed by LLNL and Parsons to evaluate the responses of optical support structures and other SSCs to seismic-induced forces.
Date: March 17, 1998
Creator: Sommer, S.C. & MacCalden, P.B.
Partner: UNT Libraries Government Documents Department

Frequency response characteristics and response spectra of base-isolated and un-isolated structures

Description: The transmissibility of seismic loads through a linear base-isolation system is analyzed using an impedance method. The results show that the system acts like a {open_quotes}low-pass{close_quotes} filter. It attenuates high-frequency loads but passes through low-frequency ones. The filtering effect depends on the vibration frequencies and damping of the isolated structure and the isolation system. This paper demonstrates the benefits and design principles of base isolation by comparing the transmissibilities and response spectra of isolated and un-isolated structures. Parameters of typical isolated buildings and ground motions of the 1994 Northridge earthquake are used for the demonstration.
Date: July 6, 1995
Creator: Mok, G.C. & Namba, H.
Partner: UNT Libraries Government Documents Department

Modeling the behavior of an earthquake base-isolated building.

Description: Protecting a structure against earthquake excitation by supporting it on laminated elastomeric bearings has become a widely accepted practice. The ability to perform accurate simulation of the system, including FEA of the bearings, would be desirable--especially for key installations. In this paper attempts to model the behavior of elastomeric earthquake bearings are outlined. Attention is focused on modeling highly-filled, low-modulus, high-damping elastomeric isolator systems; comparisons are made between standard triboelastic solid model predictions and test results.
Date: November 26, 1997
Creator: Coveney, V. A.; Jamil, S.; Johnson, D. E.; Kulak, R. F. & Uras, R. A.
Partner: UNT Libraries Government Documents Department

Identification of factors that influence the stiffness of high-damping elastomer seismic isolation bearings

Description: During the past decade, high-damping elastomer, steel-laminated seismic isolation bearings have gained acceptance as a device for isolating large buildings and structures from earthquake damage. In the United States, architectural engineering firms custom design isolators for each project and ten have the isolators manufactured by one of less than a hand-full of manufactures. The stiffness of the bearing is the single most important design parameter that the molded bearing must meet because it determines the fundamental frequency of the isolation system. This paper reports on recent research that examined several factors that cause real and potential variations to the stiffness of the bearing. The resulting changes to the fundamental frequency of the isolated structure are quantified for each factor. The following were examined: (1) dimensional tolerances, (2) frequency effects, (3) temperature effects, (4) cyclical effects, and (5) aging effects. It was found that geometric variations barely affect the stiffness whereas temperature variations greatly affect the stiffness.
Date: June 1, 1994
Creator: Kulak, R. F. & Hughes, T. H.
Partner: UNT Libraries Government Documents Department

Risk management considerations for seismic upgrading of an older facility for short-term residue stabilization

Description: Building 707 and its addition, Building 707A, were selected, after the production mission of Rocky Flats was terminated a few years ago, to stabilize many of the plutonium residues remaining at the site by 2002. The facility had undergone substantial safety improvements to its safety systems and conduct of operations for resumption of plutonium operations in the early 1990s and appeared ideally suited for this new mission to support accelerated Site closure. During development of a new authorization basis, a seismic evaluation was performed. This evaluation addressed an unanalyzed expansion joint and suspect connection details for the precast concrete tilt-up construction and concluded that the seismic capacity of the facility is less than half of that determined by previous analysis. Further, potential seismic interaction was identified between a collapsing Building 707 and the seismically upgraded Building 707A, possibly causing the partial collapse of the latter. Both the operating contractor and the Department of Energy sought a sound technical basis for deciding how to proceed. This paper addresses the risks of the as-is facility and possible benefits of upgrades to support a decision on whether to upgrade the seismic capacity of Building 707, accept the risk of the as-is facility for its short remaining mission, or relocate critical stabilization missions. The paper also addresses the Department of Energy`s policy on natural phenomena.
Date: June 1, 1999
Creator: Additon, S. L.; Peregoy, W. L. & Foppe, T. L.
Partner: UNT Libraries Government Documents Department

Application of Seismic Design Requirements to Cold Vacuum Drying (CVD) Facility Structures and Systems and Components

Description: The methodology followed in assignment of Performance Class (PC) for Natural Phenomena Hazards (NPH) seismic loads for Cold Vacuum Drying Facility (CVDF) Structures, Systems and Components is defined. The loading definition associated with each PC and structure, system and component is then defined.
Date: November 15, 1999
Creator: CREA, B.A.
Partner: UNT Libraries Government Documents Department

Evaluation of structural issues related to isolation of the 100-KE/100-KW discharge chute

Description: The issue of excessive post-seismic leakage in the discharge chute of the K East and K West fuel storage basins was resolved by designing isolation barriers to maintain basin water levels if the discharge chute should drain. This report addresses the structural issues associated with isolation of the discharge chute. The report demonstrates the structural adequacy of the components associated with chute isolation for normal and seismic loading. Associated issues, such as hardware drop accidents and seismic slosh heights are also addressed.
Date: March 10, 1995
Creator: Winkel, B.V. & Hyde, L.L.
Partner: UNT Libraries Government Documents Department

Implementation of Seismic Stops in Piping Systems

Description: Commonwealth Edison has submitted a request to NRC to replace the snubbers in the Reactor Coolant Bypass Line of Byron Station-Unit 2 with gapped pipe supports. The specific supports intended for use are commercial units designated ''Seismic Stops'' manufactured by Robert L. Cloud Associates, Inc. (RLCA). These devices have the physical appearance of snubbers and are essentially spring supports incorporating clearance gaps sized for the Byron Station application. Although the devices have a nonlinear stiffness characteristic, their design adequacy is demonstrated through the use of a proprietary linear elastic piping analysis code ''GAPPIPE'' developed by RLCA. The code essentially has all the capabilities of a conventional piping analysis code while including an equivalent linearization technique to process the nonlinear spring elements. Brookhaven National Laboratory (BNL) has assisted the NRC staff in its evaluation of the RLCA implementation of the equivalent Linearization technique and the GAPPIPE code. Towards this end, BNL performed a detailed review of the theoretical basis for the method, an independent evaluation of the Byron piping using the nonlinear time history capability of the ANSYS computer code and by result comparisons to the RLCA developed results, an assessment of the adequacy of the response estimates developed with GAPPIPE. Associated studies included efforts to verify the ANSYS analysis results and the development of bounding calculations for the Byron Piping using linear response spectrum methods.
Date: February 1, 1993
Creator: Bezler, P.; Simos, N. & Wang, Y.K.
Partner: UNT Libraries Government Documents Department

Seismic engineering for an expanded tritium facility at Los Alamos National Laboratory.

Description: An existing complex of three single story concrete and masonry shear wall buildings will be integrated into an expanded tritium facility for neutron tube target loading. Known as the NTTL Project, the expanded plant is a major element of the Department of Energy`s tritium program at the Los Alamos National Laboratory. This paper describes seismic evaluation and upgrade modifications for the 1950`s concrete shear wall building; drift analyses of two 1980`s CMU [concrete masonry unit] shear wall buildings; design of a new CMU shear wall building linking existing structures and providing personnel change room services; and design of a new steel frame building housing HVAC and electrical power and communication equipment for the complex. All buildings are closely adjacent and drift analysis to establish separation to prevent pounding is a major seismic engineering concern for the project.
Date: October 1, 1997
Creator: Volkman, D.E.; Olive, W.B.; Endebrocid, E.E.; Khan, P.K. & Rebillet, W.R.
Partner: UNT Libraries Government Documents Department

Enhancement of the basic seismic assessment of the Los Alamos National Laboratory facilities and buildings

Description: This paper presents the results of a comparison of values obtained for the seismic security of 479 buildings and facilities at Los Alamos National Laboratory following the methodology adapted from Dr. Otto Frit`s original System, and the requirements contained both in FEMA-154 ``Rapid Visual Screening of Buildings for Potential Hazards: A Handbook`` and FEMA-187 ``NEHRP Handbook for the Seismic Evaluation of Existing Buildings.`` These comparisons were made from five buildings chosen randomly illustrating a wide variety of construction types and building configurations. Each building is divided into sectors, defined as portions of it that are attached additions to the original building, or portions separated by an expansion joint between the structural systems. The five buildings studied contain a total of sixteen sectors. The paper is divided into the following sections: Introduction; Basic Concepts of the LANL Methodology; Basic Concepts of FEMA-178; Highlights of the Comparison; Comments on the Results; and Final Words.
Date: October 1, 1995
Creator: Fritz-de la Orta, G.O.
Partner: UNT Libraries Government Documents Department

Discrete optimization of isolator locations for vibration isolation systems: An analytical and experimental investigation

Description: An analytical and experimental study is conducted to investigate the effect of isolator locations on the effectiveness of vibration isolation systems. The study uses isolators with fixed properties and evaluates potential improvements to the isolation system that can be achieved by optimizing isolator locations. Because the available locations for the isolators are discrete in this application, a Genetic Algorithm (GA) is used as the optimization method. The system is modeled in MATLAB{trademark} and coupled with the GA available in the DAKOTA optimization toolkit under development at Sandia National Laboratories. Design constraints dictated by hardware and experimental limitations are implemented through penalty function techniques. A series of GA runs reveal difficulties in the search on this heavily constrained, multimodal, discrete problem. However, the GA runs provide a variety of optimized designs with predicted performance from 30 to 70 times better than a baseline configuration. An alternate approach is also tested on this problem: it uses continuous optimization, followed by rounding of the solution to neighboring discrete configurations. Results show that this approach leads to either infeasible or poor designs. Finally, a number of optimized designs obtained from the GA searches are tested in the laboratory and compared to the baseline design. These experimental results show a 7 to 46 times improvement in vibration isolation from the baseline configuration.
Date: May 17, 1996
Creator: Ponslet, E.R. & Eldred, M.S.
Partner: UNT Libraries Government Documents Department

Seismic shock and vibration isolation 1995. Part I: Theory, analysis, and testing

Description: Two basic engineering strategies for the protection of equipment and structures from damages caused by seismic shock and vibration loadings are, namely, strengthening and isolation. They work on almost totally different principles; the strengthening strategy aims primarily at increasing the capacity or the ability of the structure to withstand the dynamic loading by incorporating additional structural materials and components, while the isolation strategy focuses on reducing the demand or the transmitted loading on the structure by adding an isolator or isolation system between the structure and the source of the loading. The isolation strategy is often used for filtering out unwanted vibrations and noises. In practice, the isolation strategy has the advantage of not depending on alterations to the isolated structure and is often the preferred method for applications in equipment and in some structures.
Date: July 11, 1995
Creator: Mok, G.C. & Chung, H.H.
Partner: UNT Libraries Government Documents Department

Displacement Based Seismic Design Criteria

Description: The USNRC has initiated a project to determine if any of the likely revisions to traditional earthquake engineering practice are relevant to seismic design of the specialized structures, systems and components of nuclear power plants and of such significance to suggest that a change in design practice might be warranted. As part of the initial phase of this study, a literature survey was conducted on the recent changes in seismic design codes/standards, on-going activities of code-writing organizations/communities, and published documents on displacement-based design methods. This paper provides a summary of recent changes in building codes and on-going activities for future codes. It also discusses some technical issues for further consideration.
Date: March 29, 1999
Creator: Costello, J. F.; Hofmayer, C. & Park, Y. J.
Partner: UNT Libraries Government Documents Department

Correlation of elastomer material properties from small specimen tests and scale-size bearing tests

Description: Tests were performed on small-size elastomer specimens and scale-size laminated elastomeric bearings to correlate the material properties in shear between the two types of tests. An objective of the tests was to see how well the material properties that were determined from specimen tests could predict the response of scale-size laminated elastomeric bearings. Another objective was to compare the results of specimen test and scale-size bearing test conducted by different testing organizations. A comparison between the test results from different organizations on small specimens showed very good agreement. In contrast, the correlation of scale-size bearing tests showed differences in bearing stiffness.
Date: June 1, 1994
Creator: Kulak, R. F. & Hughes, T. H.
Partner: UNT Libraries Government Documents Department

Base isolation: Fresh insight

Description: The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.
Date: July 15, 1993
Creator: Shustov, V.
Partner: UNT Libraries Government Documents Department

Active vibration control of civil structures

Description: This is a final report of a one year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Active vibration control (AVC) of structural and mechanical systems is one of the rapidly advancing areas of engineering research. The multifaceted nature of AVC covers many disciplines, such as sensors and instrumentation, numerical modeling, experimental mechanics, and advanced power systems. This work encompassed a review of the literature on active control of structures focusing both on active control hardware and on control algorithms, a design of an isolation systems using magneto-rheological fluid-filled (MRF) dampers and numerical simulations to study the enhanced vibration mitigation effects of this technology.
Date: November 1, 1996
Creator: Farrar, C.; Baker, W.; Fales, J. & Shevitz, D.
Partner: UNT Libraries Government Documents Department