Mathematical formulation of tools for assessment of fragility and vulnerability of damaged buildings.

摘要

Major earthquakes in the past decade have caused large damage and economic losses to civil infrastructure. This has led to a fundamental rethinking of the objectives of aseismic engineering design and construction. Performance-Based Engineering (PBE) is a new approach, in which the design criteria are devised to achieve stated performance objectives when the structure is subjected to different levels of seismic demands. A related development is Consequence-Based Engineering (CBE), which aims at mitigating regional loss to civil infrastructure through selective intervention to critical components of infrastructure system.; To support the practical application of PBE and CBE, the research reported in this dissertation developed two computational techniques: (1) Interval Point Estimate Sampling (IDES), an efficient sampling technique to reduce the effort required to perform reliability analysis of structural frames subjected to earthquake ground motions and (2) Enhanced Uncoupled Modal Response History Analysis (EUMRHA), an efficient structural seismic response analysis procedure to make the analysis of the structural response less time-consuming. These techniques were used to investigate the potential for aftershocks to cause additional damage to steel moment frame buildings, and to develop simple probabilistic tools for rapid structural evaluation and condition assessment of damaged buildings.; Finally, to assess the safety condition of existing buildings, an analysis-based inspection scheme based on an associated probability model of connection damage is proposed, and a procedure to assess the performance of un-repaired building during future earthquakes is developed.