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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Integrating LiDAR Topography Into the Study of Earthquakes and Faulting

January 2011 (has links)
abstract: Meter-resolution topography gathered by LiDAR (Light Detection and Ranging) has become an indispensable tool for better understanding of many surface processes including those sculpting landscapes that record information about earthquake hazards for example. For this reason, and because of the spectacular representation of the phenomena that these data provide, it is appropriate to integrate these data into Earth science educational materials. I seek to answer the following research question: "will using the LiDAR topography data instead of, or alongside, traditional visualizations and teaching methods enhance a student's ability to understand geologic concepts such as plate tectonics, the earthquake cycle, strike-slip faults, and geomorphology?" In order to answer this question, a ten-minute introductory video on LiDAR and its uses for the study of earthquakes entitled "LiDAR: Illuminating Earthquake Hazards" was produced. Additionally, LiDAR topography was integrated into the development of an undergraduate-level educational activity, the San Andreas fault (SAF) earthquake cycle activity, designed to teach introductory Earth science students about the earthquake cycle. Both the LiDAR video and the SAF activity were tested in undergraduate classrooms in order to determine their effectiveness. A pretest and posttest were administered to introductory geology lab students. The results of these tests show a notable increase in understanding LiDAR topography and its uses for studying earthquakes from pretest to posttest after watching the video on LiDAR, and a notable increase in understanding the earthquake cycle from pretest to posttest using the San Andreas Fault earthquake cycle exercise. These results suggest that the use of LiDAR topography within these educational tools is beneficial for students when learning about the earthquake cycle and earthquake hazards. / Dissertation/Thesis / M.S. Geological Sciences 2011
322

Significance of Stress Interactions Related to the Occurrence of Shallow Slow Earthquakes / 浅部スロー地震の発生に関連した応力変化とその相互作用

Katakami, Satoshi 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22258号 / 理博第4572号 / 新制||理||1656(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)准教授 伊藤 喜宏, 教授 James Mori, 教授 岩田 知孝 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
323

Comportements nonlinéaires locaux et modélisation numérique de l’amortissement dans les structures de Génie Civil en Dynamique / Nonlinear local behaviours and numerical modeling of damping in civil engineering structures in dynamic

Heitz, Thomas 16 November 2017 (has links)
La détermination des marges de sécurité des structures de Génie Civil potentiellement sujettes à un risque sismique important nécessite l'amélioration des capacités prédictives des codes de calcul actuellement utilisés. Les phénomènes d'amortissement restent à ce jour l'une des principales sources d'incertitudes, aussi bien au niveau de la structure que des matériaux constitutifs. Pourtant, la résistance de cette dernière à un séisme est fortement conditionnée par sa capacité à stocker et à dissiper l'énergie mécanique introduite par le mouvement du sol. De meilleures modélisations et estimations de ces effets sont donc indispensables à l’évaluation du risque sismique. Cette thèse s'inscrit dans le cadre du projet RSNR SINAPS@ dont l'objectif principal est le développement d'outils de modélisation permettant d'apprécier les effets des séismes, de la rupture de la faille jusqu'au comportement vibratoire des structures et équipements. / Assessment of safety margins related to a seismic risk in Civil Engineering requires the improvement of the predictive methods usually performed. The damping phenomena still remain a major source of uncertainty both at the structure and the constitutive material levels. However, the resistance of the said structure to an earthquake is strongly conditioned by its ability to store and to dissipate the energy introduced by the ground motion. Better modeling and evaluation of these effects are therefore essential for the seismic risk assessment. This thesis takes place in the framework of the RSNR SINAPS@ project whose main objective is the improvement of modeling tools allowing to appreciate the effects of an earthquake from the rupture of the fault to the vibratory behavior of the structures and amenities.
324

Determination of earthquake intensities from chimney damage reports

Ho, Alan Darrell January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Alan Darrell Ho. / M.S.
325

Critical evaluation of seismic design criteria for steel buildings

Lefki, Lkhider January 1987 (has links)
No description available.
326

The 1852 Banda Arc Mega-thrust Earthquake and Tsunami in Indonesia

Fisher, Tsz Man 01 December 2014 (has links) (PDF)
In 1852, a five-minute long earthquake hit the Banda Arc region that was felt over most of Indonesia. It caused uplift of new islands and sent a tsunami across the Banda Sea that reached a height of 8 meters at Banda Neira and was also registered at Ambon, Saparua and other islands. Records of the 1852 earthquake at multiple locations provide the constraints needed to reconstruct the disastrous event through earthquake intensity analysis and numerical modeling of the tsunami. Using tsunami heights and arrival times as the major constraints, best fit numerical models of the tsunami were constructed using Clawpack. These models indicate that the earthquake was most likely a mega-thrust event along the Tanimbar Trough with a Mw of around 8.4. At least 10-15 meters of elastic strain energy has accumulated along the Tanimbar Through since the 1852 event, and the population in the region has increased exponentially. When another event occurs ≥ that in 1852, there will be many more people and treasure in harms way.
327

A survey of earthquake mitigation strategies & building principles for small traditional dwellings /

Weldelibanos, Fitsumberhan January 1993 (has links)
No description available.
328

Parametric Study of Friction-Damped Braced Frames with Buckling-Restrained Columns using Recommended Frame and BRC Strength Factors

Anozie, Valencia Chibuike January 2017 (has links)
No description available.
329

Application of bridge specific fragility analysis in the seismic design process of bridges in california

Dukes, Jazalyn Denise 08 April 2013 (has links)
The California Department of Transportation (Caltrans) seismic bridge design process for an Ordinary Bridge described in the Seismic Design Criteria (SDC) directs the design engineer to meet minimum requirements resulting in the design of a bridge that should remain standing in the event of a Design Seismic Hazard. A bridge can be designed to sustain significant damage; however it should avoid the collapse limit state, where the bridge is unable to resist loads due to self-weight. Seismic hazards, in the form of a design spectrum or ground motion time histories, are used to determine the demands of the bridge components and bridge system. These demands are compared to the capacity of the components to ensure that the bridge meets key performance criteria. The SDC also specifies design detailing of various components, including abutments, foundations, hinge seats and bent caps. The expectation of following the guidelines set forth by the SDC during the design process is that the resulting bridge design will avoid collapse under anticipated seismic loads. While the code provisions provide different analyses to follow and component detailing to adhere to in order to ensure a proper bridge design, the SDC does not provide a way to quantitatively determine whether the bridge design has met the requirement of no-collapse. The objectives of this research are to introduce probabilistic fragility analysis into the Caltrans design process and address the gap of information in the current design process, namely the determination of whether the bridge design meets the performance criteria of no-collapse at the design hazard level. The motivation for this project is to improve the designer's understanding of the probabilistic performance of their bridge design as a function of important design details. To accomplish these goals, a new bridge fragility method is presented as well as a design support tool that provides design engineers with instant access to fragility information during the design process. These products were developed for one specific bridge type that is common in California, the two-span concrete box girder bridge. The end product, the design support tool, is a bridge-specific fragility generator that provides probabilistic performance information on the bridge design. With this tool, a designer can check the bridge design, after going through the SDC design process, to determine the performance of the bridge and its components at any hazard level. The design support tool can provide the user with the probability of failure or collapse for the specific bridge design, which will give insight to the user about whether the bridge design has achieved the performance objective set out in the SDC. The designer would also be able to determine the effect of a change in various design details on the performance and therefore make more informed design decisions.
330

Seismic performance evaluation of port container cranes allowed to uplift

Kosbab, Benjamin David 31 March 2010 (has links)
The seismic behavior of port container cranes has been largely ignored-by owners, operators, engineers, and code officials alike. This is despite their importance to daily port operations, where historical evidence suggests that port operational downtime following a seismic event can have a crippling effect on the affected local, regional, and national economies. Because the replacement time in the event of crane collapse can be a year or more, crane collapse has the potential to be the "critical path" for post-disaster port recovery. Since the 1960's, crane designers allowed and encouraged an uplift response from container cranes, assuming that this uplift would provide a "safety valve" for seismic loading; i.e. the structural response at the onset of uplift was assumed to be the maximum structural response. However, cranes have grown much larger and more stable such that the port industry is now beginning to question the seismic performance of their modern jumbo container cranes. This research takes a step back, and reconsiders the effect that uplift response has on the seismic demand of portal-frame structures such as container cranes. A theoretical estimation is derived which accounts for the uplift behavior, and finds that the "safety valve" design assumption can be unconservative. The resulting portal uplift theory is verified with complex finite element models and experimental shake-table testing of a scaled example container crane. Using the verified models, fragility curves and downtime estimates are developed which characterize the risk of crane damage and operational downtime for three representative container cranes subjected to a range of earthquakes. This research demonstrates that container cranes designed using previous and current standards can significantly contribute to port seismic vulnerability. Lastly, performance-based design recommendations are provided which encourage the comparison of demand and capacity in terms of the critical portal deformation, using the derived portal uplift theory to estimate seismic deformation demand.

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