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Title |
Lessons form Case Studies of Incidents Associated with Seepage for Embankment Dams
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Authors |
박동순(DongSoon Park) ; 신동훈(Dong-Hoon Shin) |
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DOI |
https://doi.org/10.11112/jksmi.2025.29.2.33 |
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Keywords |
댐 안전; 침투류; 댐 누수; 필댐; 재해 경감 Dam safety; Seepage; Dam leakage; Embankment dam; Hazard mitigation |
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Abstract |
This study investigates five major earth-cored embankment dam incidents in Korea, focusing on core material degradation and seepage-related issues. Each dam exhibited unique symptoms?sinkholes, fluidized cores, wet downstream surfaces, and slope failures?yet shared a common issue: compromised impermeability of the clay core. Geotechnical and geophysical investigations revealed that this degradation was largely inhomogeneous and anisotropic, primarily due to insufficient compaction, material deficiencies, and complex geotechnical interactions. Electrical resistivity surveys identified significant heterogeneity, with critically low resistivity values indicating potential seepage paths. A key finding is that the severity of consequences varied depending on the extent and distribution of core material defects. When critical indicators of seepage failures emerged, swift and multi-tiered investigations were essential. Electrical resistivity surveys provided an effective preliminary assessment, necessitating targeted drilling for further verification. Older dams, often lacking design records, required proactive and direct investigations to preempt potential failures.
The study underscores the necessity of a government-led Incident Management System (IMS) for dam safety, integrating real-time data collection, predictive analytics, and structured response protocols. For remediation, a low-pressure permeation grouting method was implemented to restore the core layer's water barrier function. The study proposes a tiered response framework based on incident severity: preventive drainage and localized grouting for minor anomalies, targeted low-pressure grouting for moderate seepage zones, and emergency measures?such as controlled reservoir drawdowns and rapid embankment reinforcements?for severe cases. The empirical case studies and insights presented in this study serve as critical references for hazard mitigation in aging dam rehabilitation projects.
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