The close proximity to the New Madrid Seismic Zone and the significant population and infrastructure presents a potentially substantial risk for central U.S. cities such as Memphis, Tennessee. However, seismic provisions in currently adopted Memphis building codes for non-essential structures have a lower seismic design intensity level than the 2003 International Building Code (IBC) with broader acceptance nationally. As such, it is important to evaluate structures designed with these local seismic provisions to determine whether they will perform adequately during two different design-level earthquakes in this region. A four-story reinforced concrete (RC) moment frame with wide-module pan joists was designed according to current building codes relevant to the central U.S.: the 2003 IBC, the City of Memphis and Shelby County locally amended version of the 2003 IBC, and the 1999 Standard Building Code (SBC). Special moment frames (SMFs) were required for the IBC and SBC designs, but lower design forces in the amended IBC case study permitted an intermediate moment frame (IMF). However, the margin by which a SMF was required was very small for the SBC design. For slightly different conditions IMFs could be used. Nonlinear push-over and dynamic analyses using synthetic ground motions developed for Memphis for 2% and 10% probabilities of exceedance in 50 years were conducted for each of the three designs. The FEMA 356 recommended Basic Safety Objective (BSO) is to dually achieve Life Safety (LS) for the 10% in 50 years earthquake and Collapse Prevention (CP) for the 2% in 50 years earthquake. For the member-level evaluation, the SMF designs met the LS performance objective, but none of the designs met the CP performance objective or the BSO. However, the margin by which the SMF buildings exceeded CP performance was relatively small compared to that of the IMF building. Fragility curves were also developed to provide an estimate of the probability of exceeding various performance levels and quantitative performance limits. These relationships further emphasize the benefits of using an SMF as required by the IBC and, in this case, the SBC.

The Ninetyeast Ridge (NER) is a ~5000 km-long aseismic volcanic ridge trending NS in the eastern Indian Ocean basin. It is widely accepted that NER formed from the trace of a single hotspot as the Indian plate moved northward during the Late Cretaceous and Early Cenozoic due to the linear age progression from 43 Myo at the southern end to 77 Myo at the northern end. What is not fully understood is the geologic history of the ridge since its formation. This study examines the stratigraphy and sediment thickness on the ridge using new seismic data to describe the sedimentary history of NER. More than 3700 km of 2D multichannel seismic reflection profiles were collected along NER at seven sites between 5.5 degrees N and 26.1 degrees S during cruise KNOX06RR of the R/V Roger Revelle in 2007. Scientific objectives were to obtain site survey data for proposed drilling and to understand the sedimentary layers, sediment distribution, and geologic history of NER. Seismic survey sites were chosen primarily based on proximity to existing Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) drill holes (Sites 758, 216, 214, and 253) for interpretation and correlation with existing lithologic data. Seismic data were processed (filtered, stacked, and time-migrated) and interpreted using standard seismic stratigraphy principles. Three major horizons were interpreted, correlated with those previously recognized at the DSDP and ODP sites, and traced throughout the seismic data. Seismic data were categorized into three units based on distinct acoustic properties including changes in reflector amplitude, wavelength, continuity, and geometry. Seismic Unit I comprises a succession of pelagic sediments and sedimentary rock draped over Seismic Unit II, which consists of pelagic carbonates mixed with volcaniclastics. Seismic Unit III is volcanic basement. Sediment layer thicknesses and distribution were mapped at each site, and bathymetric data were correlated with seismic data to interpret geologic features. Seismic and core data indicate a common sedimentary history at each site: volcaniclastic-rich sediments deposited during or shortly after ridge formation topped by a thick drape of pelagic sediments. This history likely happened in three stages over the last ~77 My: 1) the initial subaerial or submarine emplacement of the volcanic ridge, 2) the deposition of shallow water sediments and volcaniclastics, and finally 3) the subsidence of the ridge followed by deep water pelagic sediment deposition.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 96-97). Also available via the Internet.

Thesis (M.S.)--Boise State University, 2009. / Includes abstract. Includes bibliographical references (leaves 85-90).

Thesis (Ph. D.)--University of Oregon, 2000. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 93-100). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (M.S. in Applied Physics)--Naval Postgraduate School, June 2003. / Thesis advisor(s): Steven R. Baker, Thomas G. Muir. Includes bibliographical references (p. 57-58). Also available online.

No description available.

The design of wind turbines installed in various regions of the world where earthquakes are likely must take into account loads imposed on the turbine due to ground shaking. Currently, design standards such as the International Electrotechnical Commission’s standard, IEC 61400-1, do not provide detailed guidelines for assessing loads on wind turbines due to seismic input excitation. In regions of high seismic hazard, it is extremely important to perform a thorough seismic analysis. Various simplified and full-system wind turbine models have been published and used for seismic analysis of turbine loads in recent years. Among these models, the open-source software, FAST, allows for full-system simulation of the response of wind turbines subjected to earthquake ground motion along with other sources of loading such as from the mean wind field and turbulence. This study employs this open-source software to simulate seismic loads and presents statistical and spectral summaries resulting from extensive analyses undertaken by simulating turbine response to various input motions from Western U.S. earthquakes. A total of 150 different earthquake ground motion records with varying magnitude and distance from fault rupture are selected and normalized/scaled to selected target levels prior to response simulation using a utility-scale 5-MW wind turbine model. The records selected are divided into six groups of 25 records each; the groups consist of different magnitude and distance-to-rupture values. The records in each bin are scaled to have similar demand levels as the average of the demand of the unscaled records in that bin. Two different normalization options are considered—in one, the scaling is at the rotor rotation rate (or the once-per-rev or 1P frequency); in the other, the scaling is done at the tower fore-aft first mode frequency. A study of various turbine load measures is conducted. It is found that turbine tower loads, in particular, are especially influenced by the earthquake excitation. / text

The Basin and Range province of western North America is a broad region of irregular topographic expression characterized by various styles of Cenozoic extension. Recent reprocessing and interpretation of a regional suite of industry seismic reflection profiles in southern Arizona, in the southern Basin and Range province of southwestern North America, have illuminated subsurface features related to Cenozoic crustal extension and show a detailed view of extensional processes in the southern Basin and Range. Seismic stratigraphic investigations on these profiles suggest a two-phase model for the evolution of the Catalina-Rincon metamorphic core complex, with an initial stage of isostatic core complex emplacement during detachment faulting that resulted in little topographic expression. This was followed, after a significant tectonic hiatus, by late-stage exhumation and flexural uplift of the metamorphic core complex controlled by younger high-angle faulting. Along-strike, upper-plate deformation in response to core complex emplacement was accommodated by the Santa Rita fault, south of the Catalina-Rincon metamorphic core complex. Finite-element models predicts early mechanical failure of the upper-plate of the detachment system to the south of the Catalina core complex. These models suggest that the Santa Rita fault is the result of a perturbation in the regional stress field caused by the Catalina detachment and the associated brittle failure of the upper plate from the extreme crustal extension associated with core-complex emplacement. These profiles, coupled with geologic and well control, indicate that the southwest-dipping Catalina detachment, the northwest-dipping Santa Rita fault, the east dipping Altar Valley fault, and the highly dissected Sierrita Mountains are all aspects of the same extensional event in the middle-Tertiary. These features all appear to merge into a broad zone of middle-crustal deformation and likely represent heterogeneous upper-crustal deformation in response to middle-to-lower crustal homogeneous deformation.

No description available.