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UC Berkeley Seismic Guidelines, Appendix II: Ground Motion Time Histories for the UC Berkeley Campus

Description: Three sets of ten time histories each were developed to represent the ground motions for each of the three return periods. All of the time histories are provided as pairs of fault-normal and fault-parallel components. The ground motion time histories are provided in two forms: unmodified, and spectrally modified to match the probabilistic response spectra. The unmodified time histories can be scaled to match the probabilistic response spectra at a specified period, such as the first mode period of the structure being analyzed, while leaving the shape of the response spectrum unmodified. This approach preserves the particular characteristics of the individual time history, together with the peaks and troughs of its response spectrum. These individual characteristics are modified in the spectrally matched time histories, resulting in a suite of ten time histories (for a given return period) that all have the same response spectrum for a given component (fault normal or fault parallel) that follows the smooth shape of the probabilistic response spectrum.
Date: June 3, 2003
Creator: Authors, Various
Partner: UNT Libraries Government Documents Department

UC Berkeley Seismic Guidelines, Appendix II: Ground Motion TimeHistories for the UC Berkeley Campus

Description: Three sets of ten time histories each were developed to represent the ground motions for each of the three return periods. All of the time histories are provided as pairs of fault-normal and fault-parallel components. The ground motion time histories are provided in two forms: unmodified, and spectrally modified to match the probabilistic response spectra. The unmodified time histories can be scaled to match the probabilistic response spectra at a specified period, such as the first mode period of the structure being analyzed, while leaving the shape of the response spectrum unmodified. This approach preserves the particular characteristics of the individual time history, together with the peaks and troughs of its response spectrum. These individual characteristics are modified in the spectrally matched time histories, resulting in a suite of ten time histories (for a given return period) that all have the same response spectrum for a given component (fault normal or fault parallel) that follows the smooth shape of the probabilistic response spectrum.
Date: June 3, 2003
Partner: UNT Libraries Government Documents Department

Comparison of Nonlinear Model Results Using Modified Recorded and Synthetic Ground Motions

Description: A study has been performed that compares results of nonlinear model runs using two sets of earthquake ground motion time histories that have been modified to fit the same design response spectra. The time histories include applicable modified recorded earthquake ground motion time histories and synthetic ground motion time histories. The modified recorded earthquake ground motion time histories are modified from time history records that are selected based on consistent magnitude and distance. The synthetic ground motion time histories are generated using appropriate Fourier amplitude spectrums, Arias intensity, and drift correction. All of the time history modification is performed using the same algorithm to fit the design response spectra. The study provides data to demonstrate that properly managed synthetic ground motion time histories are reasonable for use in nonlinear seismic analysis.
Date: November 1, 2011
Creator: Spears, Robert E. & Wilkins, J. Kevin
Partner: UNT Libraries Government Documents Department

Analysis of source spectra, attenuation, and site effects from central and eastern United States earthquakes

Description: This report describes the results from three studies of source spectra, attenuation, and site effects of central and eastern United States earthquakes. In the first study source parameter estimates taken from 27 previous studies were combined to test the assumption that the earthquake stress drop is roughly a constant, independent of earthquake size. 200 estimates of stress drop and seismic moment from eastern North American earthquakes were combined. It was found that the estimated stress drop from the 27 studies increases approximately as the square-root of the seismic moment, from about 3 bars at 10{sup 20} dyne-cm to 690 bars at 10{sup 25} dyne-cm. These results do not support the assumption of a constant stress drop when estimating ground motion parameters from eastern North American earthquakes. In the second study, broadband seismograms recorded by the United States National Seismograph Network and cooperating stations have been analysed to determine Q{sub Lg} as a function of frequency in five regions: the northeastern US, southeastern US, central US, northern Basin and Range, and California and western Nevada. In the third study, using spectral analysis, estimates have been made for the anelastic attenuation of four regional phases, and estimates have been made for the source parameters of 27 earthquakes, including the M{sub b} 5.6, 14 April, 1995, West Texas earthquake.
Date: February 1, 1998
Creator: Lindley, G.
Partner: UNT Libraries Government Documents Department

Validation of a ground motion synthesis and prediction methodology for the 1988, M=6.0, Saguenay Earthquake

Description: We model the 1988, M=6.0, Saguenay earthquake. We utilize an approach that has been developed to predict strong ground motion. this approach involves developing a set of rupture scenarios based upon bounds on rupture parameters. rupture parameters include rupture geometry, hypocenter, rupture roughness, rupture velocity, healing velocity (rise times), slip distribution, asperity size and location, and slip vector. Scenario here refers to specific values of these parameters for an hypothesized earthquake. Synthetic strong ground motion are then generated for each rupture scenario. A sufficient number of scenarios are run to span the variability in strong ground motion due to the source uncertainties. By having a suite of rupture scenarios of hazardous earthquakes for a fixed magnitude and identifying the hazard to the site from the one standard deviation value of engineering parameters we have introduced a probabilistic component to the deterministic hazard calculation, For this study we developed bounds on rupture scenarios from previous research on this earthquake. The time history closest to the observed ground motion was selected as a model for the Saguenay earthquake.
Date: January 1, 1998
Creator: Hutchings, L.; Jarpe, S.; Kasameyer, P. & Foxall, W.
Partner: UNT Libraries Government Documents Department

Seismic studies of the San Francisco-Oakland Bay Bridge

Description: Computational simulation plays a central role in the engineering analysis and design of major bridge structures and accurate simulations are essential for the development of earthquake resistant and economical structural designs. This paper describes new methodologies and computational tools which have recently been developed for simulating earthquake ground motions and the seismic response of cable supported bridges. The simulation tools are described and an example application for an important long-span suspension bridge is demonstrated. The application portion of the study has particular focus on the potential damaging effects of long period displacement pulses and permanent ground displacements which can occur when a bridge is located in the near-field of a major earthquake fault.
Date: August 17, 1999
Creator: Astaneh-Asl, A; Larsen, S & McCallen, D
Partner: UNT Libraries Government Documents Department

Re-alignment: It is the tunnel floor which moves, isn`t it?

Description: It is shown that on the months to years time scale, accelerator tunnels built in compacted geological strata exhibit a movement of the floor systematic (unidirectional) in each point. Attempts to characterize the movement through one global number (a <rms> deviation) based on a random model are conceptionally wrong and can only lead to erroneous design decisions for future accelerators. In the extrapolation limit, differences are especially pronounced for differential movements in the case of short (days) time spans, and for accumulated movements in the case of long (years) time spans.
Date: October 1, 1995
Creator: Pitthan, R.
Partner: UNT Libraries Government Documents Department

Utilization of near-source video and ground motion in the assessment of seismic source functions from mining explosions

Description: Constraint of the operative physical processes in the source region of mining explosions and the linkage to the generation of seismic waveforms provides the opportunity for controlling ground motion. Development of these physical models can also be used in conjunction with the ground motion data as diagnostics of blasting efficiency. In order to properly address the multi-dimensional aspect of data sets designed to constrain these sources, we are investigating a number of modem visualization tools that have only recently become available with new, high-speed graphical computers that can utilize relatively large data sets. The data sets that are combined in the study of mining explosion sources include near-source ground motion acceleration and velocity records, velocity of detonation measurements in each explosive hole, high speed film, video and shot design information.
Date: April 1, 1995
Creator: Stump, B.W. & Anderson, D.P.
Partner: UNT Libraries Government Documents Department

The Response of Long-Span Bridges to Low Frequency, Near-Fault Earthquake Ground Motions

Description: Historical seismic hazard characterizations did not include earthquake ground motion waveforms at frequencies below approximately 0.2 Hz (5 seconds period). This resulted from limitations in early strong motion instrumentation and signal processing techniques, a lack of measurements in the near-field of major earthquakes and therefore no observational awareness, and a delayed understanding in the engineering community of the potential significance of these types of motions. In recent years, there is a growing recognition of the relevance of near-fault, low frequency motions, particularly for long-period structures such as large bridges. This paper describes a computationally based study of the effects of low frequency (long-period) near-fault motions on long-span bridge response. The importance of inclusion of these types of motions for long span cable supported bridges is demonstrated using actual measured broad-band, near-fault motions from large earthquakes.
Date: February 27, 2009
Creator: McCallen, David; Astaneh-Asl, A.; Larsen, S.C. & Hutchings, Larry
Partner: UNT Libraries Government Documents Department

BOTE model: an analytic approach to predicting ground motion phenomena resulting from underground nuclear explosions

Description: An analytical model (the BOTE model) based upon a superposition of the limiting forms for the outgoing stress wave (i.e., a strong shock at early times decaying to a simple acoustic wave at later times) is presented as a means to describe the groundmotion phenomena resulting from underground nuclear explosions. Taking into account the effects of both the porosity and the water content of the surrounding medium, the BOTE model provides good agreement with both calculated and experimental data for times ranging from tens of microseconds to tens of milliseconds, and for distances ranging out to 350 ft/kt . (auth)
Date: November 1, 1973
Partner: UNT Libraries Government Documents Department

Infrasonic observation of earthquakes

Description: Infrasound signals generated by earthquakes have been detected at arrays operated by the Los Alamos National Laboratory. Three modes of propagation are possible and all have been observed by the authors. The observations suggest that regions remote from the epicenters are excited and may serve as secondary source regions. A relation is found between the normalized peak amplitudes and the seismic magnitudes.
Date: December 31, 1998
Creator: Mutschlecner, J.P. & Whitaker, R.W.
Partner: UNT Libraries Government Documents Department

Deep bore hole instrumentation along San Francisco Bay Bridges

Description: The Bay Bridges down hole network consists of sensors in bore holes that are drilled 100 ft. into bedrock around and in the San Francisco Bay. Between 2 and 8 instruments have been spaced along the Dumbarton, San Mateo, Bay, and San Rafael bridges. The instruments will provide multiple use data that is important to geotechnical, structural engineering, and seismological studies. The holes are between 100 and 1000 ft deep and were drilled by Caltrans. There are twenty- one sensor packages at fifteen sites. Extensive financial support is being contributed by Caltrans, UCB, LBL, LLNL-LDRD, U.C. Campus/Laboratory Collaboration (CLC) program, and USGS. The down hole instrument package contains a three component HS-1 seismometer and three orthogonal Wilcox 73 1 accelerometers, and is capable of recording a micro g from local M = 1.0 earthquakes to 0.5 g strong ground motion form large Bay Area earthquakes.
Date: October 1, 1998
Creator: Bakun, W.; Bowman, J.; Clymer, R.; Foxall, W.; Hipley, P.; Hollfelder, J. et al.
Partner: UNT Libraries Government Documents Department

Measurements of ground motion and magnet vibrations at the APS

Description: This article presents results of ground motion and magnet vibrations measurements at the Advanced Photon Source. The experiments were done over a wide, frequency range (0-05-100 Hz) with the use of SM-3KV-type seismic probes from the Budker Institute of Nuclear Physics (Russia). Spectral power densities of vertical and horizontal motions of the APS hall floor and quadrupoles on regular supports were obtained. Also investigated were magnet vibrations induced by designed cooling water flow and spectral characteristics of spatial correlation of the quadrupole vibrations at different sectors of the ring. The influence of personnel activity in the hall and traffic under the ring on the slow motion of storage ring elements were observed. Amplitudes of vibrations at the APS are compared with results of seismic measurements at some other accelerators.
Date: September 1, 1996
Creator: Shiltsev, V.
Partner: UNT Libraries Government Documents Department

Emittance growth due to ground motions

Description: To evaluate the dynamic emittance growth due to ground motions for a synchrotron light source, a method using the so-called transfer function. This method assumes, among others, that the displacement of the magnetic elements is equal to that of the ground. In other words, the support effects are neglected. on the other hand, another reference proposes a normal-mode method to calculate the displacement magnification due to supports. It is then natural to combine the two methods together to get a more complete picture of the vibration - emittance growth problem.
Date: October 1, 1988
Creator: Chou, W.
Partner: UNT Libraries Government Documents Department

Ambient ground motion measurements at Argonne National Laboratory over extended time periods

Description: Successful operation of the APS facility requires a very stable particle beam. Vibration coupled through mechanical systems, such as magnet supports, beam tube supports, and other paths can cause deterioration of the particle beam. There are two sources of vibration: external, or far field, which is generated external to the APS site and internal, or near field, which is generated on site and associated with operation of the facility. Internal vibration sources can be controlled or minimized using good design practices to eliminate or reduce vibration amplitudes of machinery and equipment. Depending on their origin, external vibration sources may or may not be controllable, therefore it is necessary to have sufficient knowledge of their amplitude level and frequency content to predict any adverse effects on the operation of the APS facility.
Date: March 1, 1988
Creator: Jendrzejczyk, J.A.; Wambsganss, M.W. & Smith, R.K.
Partner: UNT Libraries Government Documents Department

JARLSBERG: Containment data report

Description: Information on the JARLSBERG event at the Nevada Test Site is given. Emphasis is on stemming performance, surface motion, and satellite hole (free-field) measurements. Some of the instrumentation was rendered inoperative by a preshot lightning strike on the grounding system and the EMP. The containment was satisfactory.
Date: December 1, 1994
Creator: Hudson, B.; Stubbs, T. & Heinle, R.
Partner: UNT Libraries Government Documents Department

The development of seismic guidelines for the Stanford Linear Accelerator Center

Description: This paper describes the development of Seismic Guidelines for the Stanford Linear Accelerator Center (SLAC). Although structures have always been built conservatively, SLAC management decided to review and update their seismic guidelines. SLAC is about mid-way between the epicenters of the 8.3 Richter magnitude 1906 San Francisco and the 7.2 Loma Prieta Earthquakes. The west end of the two mile long electron/positron particle accelerator lies a half mile from the large San Andreas Fault. Suggestions for seismic planning processes were solicited from local computer manufacturing firms, universities, and federal laboratories. A Committee of the various stakeholders in SLAC`s seismic planning retained an internationally known Seismic Planning Consultant and reviewed relevant standards and drafted Guidelines. A panel of seismic experts was convened to help define the hazard, site response spectra, probabilistic analysis of shaking, and near field effects. The Facility`s structures were assigned to seismic classes of importance, and an initial assessment of a sample of a dozen buildings conducted. This assessment resulted in emergency repairs to one structure, and provided a {open_quotes}reality basis{close_quotes} for establishing the final Guidelines and Administrative Procedures, and a program to evaluate remaining buildings, shielding walls, tunnels, and other special structures.
Date: August 1, 1996
Creator: Huggins, R.
Partner: UNT Libraries Government Documents Department