State-of-the-art for Assessing Earthquake Hazards in the United States
State-of-the-art for Assessing Earthquake Hazards in the United States

Author: Otto W. Nuttli

Publisher:

Published: 1978

Total Pages: 116

ISBN-13:

DOWNLOAD EBOOK

This report is concerned with the problem of estimating credible values of the peak velocity and acceleration of the ground motion for central United States earthquakes. The report contains a catalog of all known earthquakes large enough to be felt or of body-wave magnitude greater than or equal to 3. The data of the catalog are plotted on a map, which together with structural geological information is used to identify eight seismic source zones in the central United States. The boundaries of the source zones are inexact, so that special study will be required for establishing credible ground-motion values for sites near the boundaries. A maximum-magnitude earthquake is determined for each zone, as well as a magnitude-recurrence equation. Using the Murphy-O'Brien formulation, as well as theoretical results of Herrmann and a limited amount of strong-motion data for the central United States, equations are derived for that region which relate maximum horizontal acceleration and velocity to body-wave magnitude and epicentral distance. (Author).

State-of-the-art for Assessing Earthquake Hazards in the United States
State-of-the-art for Assessing Earthquake Hazards in the United States

Author: Charles E. Glass

Publisher:

Published: 1978

Total Pages: 248

ISBN-13:

DOWNLOAD EBOOK

Recent advances in the fields of remote sensing, engineering geology, seismology, and earthquake engineering have developed a need for a systematic comprehensive review of the basic principles and methods of applying remote sensing for evaluation of earthquakes hazards and seismic risk. This paper responds to this need by reviewing basic concepts, summarizing essential, state-of-the-art knowledge of theory and instrumental methods, establishing procedures evaluations, and discussing representative case histories that illustrate earthquake hazard evaluations that are based on remote sensing analysis. The approach that is recommended is based on a 'multi' approach that uses an integrated and systematic study of a region or a fault with a variety of imagery varying from small-scale (synoptic) to large-scale (detailed). The imagery analysis should be followed by a ground verification program of study that should include both ground and aerial reconnaissance examination of the major geologic structures of concern. The character of the earthquake hazards is discussed in the context of the lithologic, structural, vegetational, and topographic variations that are associated with different types of active geologic structures. The response of earth materials, landforms, and geologic structures is summarized for the several main types of passive and active electromagnetic radiation used in current remote-sensing practice. Limitations of the different spectral regions used in remote sensing are reviewed to assist in the selection of ideal methods or sequences of methods of study for effective evaluation of active or capable faults and for assessing the earthquake potential of geological structures that may affect a given engineering site.

State of the Art Assessing Earthquake Hazards in the United States
State of the Art Assessing Earthquake Hazards in the United States

Author: E. L. Krinitzsky

Publisher:

Published: 1974

Total Pages: 98

ISBN-13:

DOWNLOAD EBOOK

"Earthquakes of engineering interest are normally considered to result only from slippage or movement along existing faults. Hence, the detection of existing faults and their assessment as active or inactive constitutes an essential aspect of earthquake design. Some faults in soft sediments, through active, may not have the capability of generating earthquakes and must be so interpreted. Active faults generally may be evaluated for their maximum capacity to generate earthquakes through a synthesis of the local geologic and seismic history and worldwide relationships between fault dimensions earthquakes. Major earthquakes are caused by slippage along large faults, which are unlikely to be missed in detailed geologic investigations for sites in western United States. This may not be the case in the central and eastern United States. Small faults may be missed in any investigation so that a floating earthquake of limited size must be assumed to account for them. When faulting is not manifest at the surface, seismic history and geologic investigations can define geographic limits or zones for which floating earthquakes of various sizes are assigned"--Page ix.

State of the Art and Practice in the Assessment of Earthquake-Induced Soil Liquefaction and Its Consequences
State of the Art and Practice in the Assessment of Earthquake-Induced Soil Liquefaction and Its Consequences

Author: National Academies of Sciences, Engineering, and Medicine

Publisher:

Published: 2019-01-30

Total Pages: 350

ISBN-13: 9780309440271

DOWNLOAD EBOOK

Earthquake-induced soil liquefaction (liquefaction) is a leading cause of earthquake damage worldwide. Liquefaction is often described in the literature as the phenomena of seismic generation of excess porewater pressures and consequent softening of granular soils. Many regions in the United States have been witness to liquefaction and its consequences, not just those in the west that people associate with earthquake hazards. Past damage and destruction caused by liquefaction underline the importance of accurate assessments of where liquefaction is likely and of what the consequences of liquefaction may be. Such assessments are needed to protect life and safety and to mitigate economic, environmental, and societal impacts of liquefaction in a cost-effective manner. Assessment methods exist, but methods to assess the potential for liquefaction triggering are more mature than are those to predict liquefaction consequences, and the earthquake engineering community wrestles with the differences among the various assessment methods for both liquefaction triggering and consequences. State of the Art and Practice in the Assessment of Earthquake-Induced Soil Liquefaction and Its Consequences evaluates these various methods, focusing on those developed within the past 20 years, and recommends strategies to minimize uncertainties in the short term and to develop improved methods to assess liquefaction and its consequences in the long term. This report represents a first attempt within the geotechnical earthquake engineering community to consider, in such a manner, the various methods to assess liquefaction consequences.