This project is a continuation of earlier research work by the Principal Investigator in support of the Earthquake Engineering Research Program, under the direction of the USAE Waterways Experiment Station at Vicksburg, Mississippi. The program of experiments investigating the earthquake behavior and liquefaction of deep sand deposits has generated a large body of data for analysis. This Final Technical Report describes the database that has been developed to date and presents the analysis and the initial conclusions of the study. Data of excess pore pressures at different depths is used to deduce the onset of liquefaction under different initial effective overburden stresses. The object of the research is to compute the factor K(sigma), widely used in design calculations to relate the liquefaction resistance at high effective confining stresses to the strength deduced from laboratory experiments at 1 tsf. By comparing the data obtained from the centrifuge experiments with standard design approaches for the prediction of liquefaction, an assessment of the relationship between K(sigma) and depth can be made. This is discussed and areas where further experimental work is required are highlighted. The results are also presented in the form of log-log (stress focus) plots and compared with laboratory element test data. Preliminary conclusions indicate that the centrifuge data more closely match relationships based on field experience than laboratory data.

This project is a continuation of earlier research work by the Principal Investigator in support of the Earthquake Engineering Research Program, under the direction of the USAE Waterways Experiment Station at Vicksburg, Mississippi. The program of experiments investigating the earthquake behavior and liquefaction of deep sand deposits has generated a large body of data for analysis. This Final Technical Report describes the database that has been developed to date and presents the analysis and the initial conclusions of the study. Data of excess pore pressures at different depths is used to deduce the onset of liquefaction under different initial effective overburden stresses. The object of the research is to compute the factor K(sigma), widely used in design calculations to relate the liquefaction resistance at high effective confining stresses to the strength deduced from laboratory experiments at 1 tsf. By comparing the data obtained from the centrifuge experiments with standard design approaches for the prediction of liquefaction, an assessment of the relationship between K(sigma) and depth can be made. This is discussed and areas where further experimental work is required are highlighted. The results are also presented in the form of log-log (stress focus) plots and compared with laboratory element test data. Preliminary conclusions indicate that the centrifuge data more closely match relationships based on field experience than laboratory data.

Earthquake engineering is the ultimate challenge for structural engineers. Even if natural phenomena such as earthquakes involve great uncertainties, structural engineers need to design buildings, bridges, and dams capable of resisting the destructive forces produced by earthquakes. However, structural engineers must rely on the expertise of other specialists to realize these projects. Thus, this book not only focuses on structural analysis and design, but also discusses other disciplines, such as geology, seismology, and soil dynamics, providing basic knowledge in these areas so that structural engineers can better interact with different specialists when working on earthquake engineering projects."

The book Earthquake Engineering - From Engineering Seismology to Optimal Seismic Design of Engineering Structures contains fifteen chapters written by researchers and experts in the fields of earthquake and structural engineering. This book provides the state-of-the-art on recent progress in the field of seimology, earthquake engineering and structural engineering. The book should be useful to graduate students, researchers and practicing structural engineers. It deals with seismicity, seismic hazard assessment and system oriented emergency response for abrupt earthquake disaster, the nature and the components of strong ground motions and several other interesting topics, such as dam-induced earthquakes, seismic stability of slopes and landslides. The book also tackles the dynamic response of underground pipes to blast loads, the optimal seismic design of RC multi-storey buildings, the finite-element analysis of cable-stayed bridges under strong ground motions and the acute psychiatric trauma intervention due to earthquakes.

This report describes the initial findings of an experimental study supported by the U.S. Army Centrifuge Research Center and Engineer Earthquake Engineering Research Program (EQEN) into the behavior of saturated sands under high initial effective confining stresses subjected to strong ground shaking. The research was conducted using the Army Centrifuge at the U.S. Army Engineering Research and Development Center (ERDC), located in Vicksburg MS, formerly known as the Waterways Experiment Station (WES). The centrifuge studies have shown that the generation of excess pore pressure is limited to a level less than 100 percent for vertical effective confining stresses exceeding around 3 atmospheres (atm, or 300 KPa). This limit reduces at higher confining stresses. It is likely that this limit is a function of a range of variables, including amplitude of shaking. A second key finding indicates that dense layers overlying loose layers may still be readily liquefied as a consequence of the high excess pore pressures generated below. If verified, the potential benefits from these findings for the design of remediation works for large earth dams could be substantial. The report describes the equipment used for the experiments, the research program, and presents the initial results, contrasting the development of excess pore pressure at low confining stress with that at high confining stress. Possible consequences for a hypothetical dam are discussed.

Fundamentals of Earthquake Engineering combines aspects of engineering seismology, structural and geotechnical earthquake engineering to assemble the vital components required for a deep understanding of response of structures to earthquake ground motion, from the seismic source to the evaluation of actions and deformation required for design. The nature of earthquake risk assessment is inherently multi-disciplinary. Whereas Fundamentals of Earthquake Engineering addresses only structural safety assessment and design, the problem is cast in its appropriate context by relating structural damage states to societal consequences and expectations, through the fundamental response quantities of stiffness, strength and ductility. The book is designed to support graduate teaching and learning, introduce practicing structural and geotechnical engineers to earthquake analysis and design problems, as well as being a reference book for further studies. Fundamentals of Earthquake Engineering includes material on the nature of earthquake sources and mechanisms, various methods for the characterization of earthquake input motion, damage observed in reconnaissance missions, modeling of structures for the purposes of response simulation, definition of performance limit states, structural and architectural systems for optimal seismic response, and action and deformation quantities suitable for design. The accompanying website at www.wiley.com/go/elnashai contains a comprehensive set of slides illustrating the chapters and appendices. A set of problems with solutions and worked-through examples is available from the Wley Editorial team. The book, slides and problem set constitute a tried and tested system for a single-semester graduate course. The approach taken avoids tying the book to a specific regional seismic design code of practice and ensures its global appeal to graduate students and practicing engineers.

Fundamentals of Earthquake Engineering: From Source to Fragility, Second Edition combines aspects of engineering seismology, structural and geotechnical earthquake engineering to assemble the vital components required for a deep understanding of response of structures to earthquake ground motion, from the seismic source to the evaluation of actions and deformation required for design, and culminating with probabilistic fragility analysis that applies to individual as well as groups of buildings. Basic concepts for accounting for the effects of soil-structure interaction effects in seismic design and assessment are also provided in this second edition. The nature of earthquake risk assessment is inherently multi-disciplinary. Whereas this book addresses only structural safety assessment and design, the problem is cast in its appropriate context by relating structural damage states to societal consequences and expectations, through the fundamental response quantities of stiffness, strength and ductility. This new edition includes material on the nature of earthquake sources and mechanisms, various methods for the characterization of earthquake input motion, effects of soil-structure interaction, damage observed in reconnaissance missions, modeling of structures for the purposes of response simulation, definition of performance limit states, fragility relationships derivation, features and effects of underlying soil, structural and architectural systems for optimal seismic response, and action and deformation quantities suitable for design. Key features: Unified and novel approach: from source to fragility Clear conceptual framework for structural response analysis, earthquake input characterization, modelling of soil-structure interaction and derivation of fragility functions Theory and relevant practical applications are merged within each chapter Contains a new chapter on the derivation of fragility Accompanied by a website containing illustrative slides, problems with solutions and worked-through examples Fundamentals of Earthquake Engineering: From Source to Fragility, Second Edition is designed to support graduate teaching and learning, introduce practising structural and geotechnical engineers to earthquake analysis and design problems, as well as being a reference book for further studies.

The Network for Earthquake Engineering Simulation (NEES), administered by the National Science Foundation (NSF), is scheduled to become operational in 2004. These network sites will perform a range of experiments to test and validate complex computer models being developed to simulate the behavior of structures subjected to earthquakes. To assist in this effort, the NSF requested the National Research Council(NRC) to frame the major questions to be addressed by and to develop a long-term research agenda for NEES. Preventing Earthquake Disasters presents an overview of the grand challenge including six critical research problems making up that challenge. The report also provides an assessment of earthquake engineering research issues and the role of information technology in that research effort, and a research plan for NEES.

This book has been brought out in remembrance of Prof. DK Paul who has contributed immensely to the domain of Earthquake Engineering and Earthquake Disaster Mitigation. Prof. Paul was a leading authority in this field and has made significant contributions in Earthquake Resistant Analysis as well as Design of various special structures, which resulted in earthquake disaster reduction in India. This book comprises recent diverse topics on earthquake engineering and disaster mitigation. The chapters are of interest to readers, as the different chapters will elaborate popular topics on various aspects of earthquake engineering and disaster management. Substantial research work has been carried out in the domain of earthquake engineering for understanding the underlying phenomena as well as to attain relevance in mitigating disaster. Under overarching umbrella of earthquake engineering and technology, systematic categorization of various ongoing research details pertaining to earthquake engineering and disaster management has been introduced in this book. The chapters appended in this book not only comprise detailed understanding of the responses of soil and structure under the implications of seismic loading but also address some of the innovative ways to cater the implications of severe loading conditions. Further, this book also introduces specific case studies pertaining to various regions of India, which will aid the readers to attain a detailed idea about the seismic aspects of those regions in order to undergo further research. This also aids in mitigating potential hazards due to future earthquakes in terms of taking proper remedial measures. The appended chapters comprise in-depth knowledge about several aspects on earthquake engineering such as nonlinear seismic response of both superstructures and embedded structures, design spectrum, amplification prediction, simulation with the aid of stochastic approaches, seismic performance of structures as well as earthquake induced disasters. The aforementioned wide-ranging topics pertaining to earthquake engineering and disaster management aid in substantial development in futuristic research and employ innovative ways to cater the needs of mitigating disasters. All the chapters consist of proper illustrations and tables which makes it easy to comprehend the vital concepts for the readers as well as aids in implementing new aspects in the field in addition to classroom learning.