Table 4: Material Properties used for Sliding Stability Analyses

* For silt, we adopted a total unit weight in the vertical direction of 120 pcf and an equivalent fluid pressure in the horizontal direction of 85 pcf in general accordance with recommendations in Ref. 3. The resulting Ka for 85pcf/120pcf is 0.71.

Material Total Unit Weight (pcf) Friction Angle (?, degrees) Earth Pressure Coefficients Friction Factor
Active (Ka) Passive (Kp) (tanδ)
Sand 115 29° 0.3 3.25 0.55
Silt 120* 28° 0.71* n/a n/a
Water 62.5 n/a n/a n/a n/a
RCC 150 n/a n/a n/a n/a