SEASONAL VARIATION IN THE SHEAR STRENGTH BEHAVIORS OF LANDSLIDE SOIL FROM THE SIWALIK HILLS OF NEPAL
In the rainy season, shear strength values range from 16 to 27 kPa, while in the dry season, it ranges from 22 to 38 kPa. Between the two seasons, there is a large variation in shear strength. In the rainy season, the angle of internal friction of the soils ranges from 7o to 14o, whereas in the dry season, it ranges from 17o to 33o. The strain/stress curves of soils show considerable peaks in the dry season, while no peaks are visible in the wet season. The result demonstrates that during the wet season, the shear strength and shear strength parameters of slope soil decreased and became minimum. The decline in shear strength behaviors eventually results the landslide in the Siwalik Hills of Nepal.
Key words: seasonal variation, shear strength, Siwalik, Nepal