A Rational Approach to Damage Mitigation in Existing Structures Exposed to Earthquakes.

摘要

This study examined the feasibility of developing a rational decision analysis methodology to be used by building owners and managers as well as the financial and insurance industries in the evaluation of possible modification schemes for existing buildings exposed to a predicted earthquake. Available procedures to determine the expected earthquake hazard at a given site were studied,and a methodology to apply the results of these procedures to the decision-making process is presented. A procedure to calculate the damages to various components of a building due to different levels of ground shaking was developed. To provide flexibility for future development,the indirect damages related to events like fire and substructure failure and their respective probabilities were also included. A computer program, DAMSTAT,was developed to automate the calculation steps for this proposed methodology. A description,listing,and application of this computer program is presented. The usefulness of the methodology greatly depends on the ability to estimate the damages to a building due to a given earthquake intensity. Therefore, a method to generate damage matrices from historical damage data was developed to successfully estimate the expected damage. This method was applied to masonry buildings,and a number of damage statistics curves were generated for four classes of masonry buildings. Results of an extensive literature search,performed to gather information on the performance of the older masonry Type III low-rise building during previous seismic events,are reported.