MCEER Special Report on Multiple Hazard Bridge Design: Design of Highway Bridges Against Extreme Hazard Events - Issues, Principles and Approaches; Special rept

摘要

After visiting areas affected by major natural and manmade disasters during the past several years in the U.S. and abroad, the authors of this report identified a need to consider the development of multi-hazard design principles and guidelines for highway bridges. They began by reviewing existing information with the aim to expand the methods and approaches established in earthquake engineering. During the past two years, a number of exploratory studies have been carried out to define a potential research project that may be accomplished within a period of several years with a moderate but reasonable budget. These pilot studies included the following: (1) Understand the physical conditions of existing bridges and current methods of bridge design, retrofit and inspection; (2) Identify current philosophical approaches to handle multi-hazard (extreme events) load effects on highway bridges; (3) Perform scenario studies of possible damage in a typical highway bridge model due to various extreme hazard loadings; (4) Explore various means to compare some extreme hazards and their load effects; (5) Examine the suitability of using the return period as the basis for comparing different hazards; and (6) Conduct uncertainty analysis of extreme hazard models. The studies revealed the complex nature of establishing multi-hazard design principles and guidelines for highway bridges, since there are so many interrelated parameters to be examined within many different contexts for consideration of importance and priorities. Furthermore, there is insufficient information on hazard occurrences and their load effects on the capacity of bridges, such as damage data, etc. In order to begin to establish a research agenda, the authors organized a special workshop attended by a variety of experts including experienced designers, stakeholders, code authors and researchers. The participants offered their views and opinions on key issues and principles in the multi-hazard design of highway bridges from their unique perspectives. Their papers comprise this report.