New Challenges For Seismic Risk Mitigation In Urban Areas

Urban seismic risk is growing worldwide and is, increasingly, a problem of developing countries. In 1950, one in four of the people living in the world's fifty largest cities was earthquake-threatened, while in the year 2000, about one in two will be. Further, ofthose people living in earthquake-threatened cities in 1950, about two in three were located in developing countries, while in the year 2000, about nine in ten will be. Unless urban seismic safety is improved, particularly in developing countries, future earthquakes will have ever more disastrous social and economic consequences. In July 1992, an international meeting was organized with the purpose of examining one means ofimproving worldwide urban safety. Entitled "Uses ofEarthquake Damage Scenarios for Cities of the 21st Century," this meeting was held in conjunction with the Tenth World Conference ofEarthquake Engineering, in Madrid, Spain. An earthquake damage scenario (EDS) is adescription of the consequences to an urban area of a large, but expectable earthquake on the critical facilities of that area. In Californian and Japanese cities, EDSes have been used for several decades, mainly for the needs of emergency response officials. The Madrid meeting examined uses of this technique for other purposes and in other, less developed countries. As a result of this meeting, it appeared that EDSes bad significant potential to improve urban seismic safety worldwide.

Earthquakes affecting urban areas can lead to catastrophic situations and hazard mitigation requires preparatory measures at all levels. Structural assessment is the diagnosis of the seismic health of buildings. Assessment is the prelude to decisions about rehabilitation or even demolition. The scale of the problem in dense urban settings brings about a need for macro seismic appraisal procedures because large numbers of existing buildings do not conform to the increased requirements of new earthquake codes and specifications or have other deficiencies. It is the vulnerable buildings - liable to cause damage and loss of life - that need immediate attention and urgent appraisal in order to decide if structural rehabilitation and upgrading are feasible. Current economic, efficient and occupant-friendly rehabilitation techniques vary widely and include the application either of precast concrete panels or layers, strips and patches of fiber reinforced polymers (FRP) in strategic locations. The papers in this book, many by renowned authorities in earthquake engineering, chart new and vital directions of research and application in the assessment and rehabilitation of buildings in seismic regions. While several papers discuss the probabilistic prediction and quantification of structural damage, others present approaches related with the in-situ and occupant friendly upgrading of buildings and propose both economical and practical techniques to address the problem.

​The classical field dealing with earthquakes is called “earthquake engineering” and considered to be a branch of structural engineering. In projects dealing with strategies for earthquake risk mitigation, urban planning approaches are often neglected. Today interventions are needed on a city, rather than a building, scale. This work deals with the impact of earthquakes, including also a broader view on multihazards in urban areas. Uniquely among other works in the field, particular importance is given to urban planning issues, in conservation of heritage and emergency management. Multicriteria decision making and broad participation of those affected by disasters are included.

This book presents practical guidelines and recommendations for the design in seismic-prone regions. It is based on extensive research and it includes original drawings and sketches at the macro and micro levels. It is the first time that an attempt has been made to publish a book on urban design in the seismic-prone regions, covering the needs of government officials, planners, economists, architects, engineers and scientists, with the purpose of planning for seismic risk reduction and the practical implementation of methodologies and findings in earthquake affected regions. The guidelines presented are expected to be immensely beneficial to all countries in the earthquake prone regions, particularly in the developing world.

This book brings together a series of theory and practice essays on risk management and adaptation in urban contexts within a resilient and multidimensional perspective. The book proposes a transversal approach with regard to the role of spatial planning in promoting and fostering risk management as well as institutions’ challenges for governing risk, particularly in relation to new forms of multi-level governance that may include stakeholders and citizen engagement. The different contributions focus on approaches, policies, and practices able to contrast risks in urban systems generating social inclusion, equity and participation through bottom-up governance forms and co-evolution principles. Case studies focus on lessons learned, as well as the potential and means for their replication and upscaling, also through capacity building and knowledge transfer. Among many other topics, the book explores difficulties encountered in, and creative solutions found, community and local experiences and capacities, organizational processes and integrative institutional, technical approaches to risk issue in cities.

This collection focuses on the development of novel approaches to address one of the most pressing challenges of civil engineering, namely the mitigation of natural hazards. Numerous engineering books to date have focused on, and illustrate considerable progress toward, mitigation of individual hazards (earthquakes, wind, and so forth.). The current volume addresses concerns related to overall safety, sustainability and resilience of the built environment when subject to multiple hazards: natural disaster events that are concurrent and either correlated (e.g., wind and surge); uncorrelated (e.g., earthquake and flood); cascading (e.g., fire following earthquake); or uncorrelated and occurring at different times (e.g., wind and earthquake). The authors examine a range of specific topics including methodologies for vulnerability assessment of structures, new techniques to reduce the system demands through control systems; instrumentation, monitoring and condition assessment of structures and foundations; new techniques for repairing structures that have suffered damage during past events, or for structures that have been found in need of strengthening; development of new design provisions that consider multiple hazards, as well as questions from law and the humanities relevant to the management of natural and human-made hazards.

Great loss of human life, structural damage, and social and economic upheaval occur repeatedly due to such natural hazards as earthquakes, typhoons, hurricanes, landslides, floods and tsunamis. Both the US and Taiwan, along with many other countries, have a history of such occurrences and a common need to reduce their effects. This volume includes papers from the fourth symposium workshop, held jointly between the US and Taiwan to discuss research and its application to multiple hazard mitigation. The workshop, Urban Disaster Mitigation, The Role of Engineering and Technology, discussed lessons learned from recent natural disasters; assessed results of Taiwan's multiple hazards research program and potential application to the US; and proposed further studies on subjects of mutual concern. Topics include recent scientific findings obtained in various natural hazard areas and assessment of actual and potential damage from earthquakes, floods and landslides. Of particular importance are measures that can be taken to mitigate these hazards ranging from use of new algorithms for structural engineering to warning systems for a given region. At a time when natural disasters are widespread, engineers play a key role. Construction methods and building codes are changing; current knowledge shapes the direction of these changes. The research results presented in these proceedings will benefit both the academic and practicing communities around the world, strengthening the relationship between these two important parties.