Fig. 1. Study area (Sindun-myeon, Icheon-si, Gyeonggi-do) with landslide location.
Fig. 2. Geological map of the study area (source: KIGAM).
Fig. 3. Modified infinite slope model (Chae te al., 2012) considering saturation depth ratio.
Fig. 4. Soil test results and soil database development.
Fig. 5. Thematic maps for the physical properties from the analysis result of the soil in the study area.
Fig. 6. Thematic maps for predicting soil thickness in the study area.
Fig. 7. Distribution of the FS evaluated using the return period. The geographical features of the graded areas have between 20 - 50° slope; those not in compliance with this feature are excluded as a null.)
Fig. 8. Landslide risk grade ratio evaluated for each return period.
Fig. 9. Comparison of the relationship between soil depth and saturated depth ratio.
Fig. 10. Comparison of the relationship between slope and saturated depth ratio.
Fig. 11. Landslide risk index grade of the specific area (Inhu-ri) for the return period.
Table 1. Range of FS for each grade.
Table 2. Classification and evaluation of FS with the grade for each return period
Table 3. Landslide risk index (LRI) of the specific area (Inhu-ri).
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