Abstract
Earthquake response observation and vibration tests were examined for evaluating dynamic characteristics of soil-structure system of existing buildings. Approximately 150 buildings have been tested and observed in the past 15 years. Based on the results, new strategic response observation program is proposed, which reveals appropriate combination of limited observation in systematic way. Detailed discussion is made for some important points concerning planning of observation, new equipments and operation, data analysis and database, and future aspects of earthquake response observation.