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.

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.

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.

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.

Throughout the past few years, there has been extensive research done on structural design in terms of optimization methods or problem formulation. But, much of this attention has been on the linear elastic structural behavior, under static loading condition. Such a focus has left researchers scratching their heads as it has led to vulnerable structural configurations. What researchers have left out of the equation is the element of seismic loading. It is essential for researchers to take this into account in order to develop earthquake resistant real-world structures. Structural Seismic Design Optimization and Earthquake Engineering: Formulations and Applications focuses on the research around earthquake engineering, in particular, the field of implementation of optimization algorithms in earthquake engineering problems. Topics discussed within this book include, but are not limited to, simulation issues for the accurate prediction of the seismic response of structures, design optimization procedures, soft computing applications, and other important advancements in seismic analysis and design where optimization algorithms can be implemented. Readers will discover that this book provides relevant theoretical frameworks in order to enhance their learning on earthquake engineering as it deals with the latest research findings and their practical implementations, as well as new formulations and solutions.

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 report summarizes the 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. A large dataset of the response of saturated sand to dynamic shaking under

This book is the expanded version of the earlier (first edition) text. It presents new comprehensive rational quantitative theories (utilizing fundamental energy concepts throughout) covering the entire earthquake event from the point of view of the engineer. It starts with a mathematical analysis of an underground mechanism (the earthquake), then proceeds to determinations of the timewise and spacewise variations of the fundamental engineering damage-design parameter, the ground energy. Finally, the new theories are applied to a number of typical (actual) structural and non-structural design problems. Each chapter of the first edition has now been improved and enlarged and new chapters have been added to include recent research by the author and his graduate students.

"This book summarizes the most essential concepts that every engineer designing a new building or evaluating an existing structure should consider to control the damage caused by drift (deformation) induced by earthquakes. It presents the work on earthquake engineering done by Dr. Mete Sozen and dozens of his collaborators and students over decades of experimentation, analysis, and reconnaissance. Many of the concepts produced through this work are integral part of earthquake engineering today. Nevertheless, the connection between the concepts in use today and the original sources is not always explained. Drift-Driven Design of Buildings summarizes Sozen's research, provides common language and notation from subject to subject, provides examples and supporting data, and adds historical context as well as class notes that were the result of Sozen's dedication to teaching. It distills reinforced concrete building design to resist earthquake demands to its essence in a way that no other available book does. The recommendations provided are not only essential but also of the utmost simplicity - which is not the result of uninformed neglect of relevant parameters but rather the result of careful consideration and selection of parameters to retain only those that are most critical. Features: Provides the reader with a clear understanding of the essential features that control the seismic response of RC buildings, describes a simple (perhaps the simplest) seismic design method available, includes the underlying hard data to support and explain the methods described, and presents decades of work by one of the most prolific and brilliant civil engineers in the United States in the second half of the 20th century. Drift-Driven Design of Buildings serves as a useful guide for civil and structural engineering students for self-study or in-class learning, as well as instructors and practicing engineers"--