Directions in Strong Motion Instrumentation


Book Description

Strong ground motion measuring and recording instruments play a major role in mitigation of seismic risk. The strong ground motion near the source of an earthquake describes the effects that endanger our built environment, and is also the most detailed clue concerning the source mechanism of the earthquake. The range of complexity that engulfs our understanding of the source parameters of a major earthquake (extent of the source mechanism, stress drop, wave propagation patterns) and how buildings and other works of construction respond to ground-transmitted dynamic effects may be overpowered by improved direct observations. Strong motion seismographs provide the information that enables scientists and engineers to resolve the many issues that are intertwined with practical problems of building safe communities worldwide. They may be installed as arrays close to major fault zones, consisting of many instruments arranged in some geometrical pattern, or in the vicinity and mounted on buildings. This book, which contains papers by invited authorities, represents a unique interaction between seismologists and earthquake engineers who examine issues of mutual concern in an overlapping area of major interest. The papers have been grouped around three major areas. -Seismic Hazard and Extreme Motions -Engineering Uses of Strong Motion Seismograms -Arrays and Observations.




Seismic Risk Assessment and Retrofitting


Book Description

Many more people are coming to live in earthquake-prone areas, especially urban ones. Many such areas contain low-rise, low-cost housing, while little money is available to retrofit the buildings to avoid total collapse and thus potentially save lives. The lack of money, especially in developing countries, is exacerbated by difficulties with administration, implementation and public awareness. The future of modern earthquake engineering will come to be dominated by new kinds of measuring technologies, new materials developed especially for low-rise, low-cost buildings, simpler and thus lower cost options for retrofitting, cost cutting and raising public awareness. The book covers all the areas involved in this complex issue, from the prevention of total building collapse, through improvement techniques, to legal, financial, taxation and social issues. The contributors have all made valuable contributions in their own particular fields; all of them are or have been closely involved with the issues that can arise in seismic zones in any country. The recent research results published here offer invaluable pointers to practicing engineers and administrators, as well as other scientists whose work involves saving the lives and property of the many millions of people who live and work in hazardous buildings.




Earthquakes and Health Monitoring of Civil Structures


Book Description

Health monitoring of civil structures (HMS) is a new discipline, which contributes to successful and on time detection of damages to structures. This book is a collection of chapters on different topics written by leading scientists in the field. It is primarily focused on the latest achievements in monitoring the earthquake effect upon the health of civil structures. The first chapter of the book deals with the geotechnical and structural aspects of the 2010-2011 Christchurch earthquakes. Further chapters are dedicated to the latest HMS techniques of identification of damage to structures caused by earthquakes. Real time damage detection as well as sensors and acquisition systems used for that purpose are presented. The attention is focused on automated modal analysis, dynamic artificial neural networks and wavelet techniques used in HMS. Particular emphasis is put on wireless sensors and piezo-impendance transducers used for evaluation of seismically induced structural damage. The discussion is followed by presentation of case studies of application of health monitoring for buildings and other civil structures, including a super tall structure. The book ends with a presentation of shaking table tests on physical models for the purpose of monitoring their behaviour under earthquake excitation. Audience The book is primarily intended for engineers and scientists working in the field of application of the HMS technique in earthquake engineering. Considering that real time health monitoring of structures represents a sophisticated approach applying the latest techniques of monitoring of structures, many experts from other industries will also find this book useful.