A Study on Seismic Behaviors of Earth-Filled Embankment with Intact and Deteriorated Core Using Centrifuge Model Tests

摘要

Janghyeon dam, located at Gangneung-si with 6.9 m height and constructed in 1947, is modeled at a scale of 1:60 to analyze the seismic behaviors of the dam during seismic loading through dynamic centrifuge model tests. The centrifuge model tests are performed by simulating the field stress conditions and seismic loads. The results of dynamic centrifuge model tests show that the dam with an intact core satisfies the stability criteria against crest settlement. In contrast, a settlement of 1.2% of the dam height suggests that the dam with a deteriorated core does not satisfy the stability criteria. The acceleration amplification ratio from the core base to crest is 1.1-1.6 in the case of the intact dam and is 1.15-2.32 in the case of the deteriorated dam. Thus, it is inferred that the acceleration and settlement responses rely not only on seismic loads but also on the condition of the dam (i.e., intact or deteriorated). The acceleration amplification and settlement in the deteriorated dam are observed to be apparent. This is due to the weakening phenomenon of the dam by water that seeps through the deteriorated core, which increases pore water pressure and saturation level. Thus, the dynamic behaviors of the earth-filled dam, obtained through this study, can be used as primary data for seismic design and reinforcement of dam.