Stability Assessment of Cut Slopes Along Kasara Ghat on National Highway 3

The Western Ghats are a highly intricate and diverse terrain located within the Indian subcontinent. The region's unique topography, characterized by steep rock slopes, poses inherent challenges, including the risk of slope destabilization. The excavation made during the construction of the National Highway has been predominantly responsible for the future destabilization. A field-intensive study was conducted for the selected area with laboratory testing. Different vulnerable location-based samples of rocks and soils were tested in the laboratory to check their properties and strength. Out of 11 slopes, 7 slopes were considered for evaluation, and 1 slope (Location 6) had already failed (FoS was 0.86) in the last rainy season (in the month of September 2025). 2 slopes (Location 1 Slope 1, Location 2 Slope 2) were severely fractured (FoS less than 1) and thus need immediate attention. The remaining 4 slopes are highly weathered (expected to fail in the next few years). Rock sample results are compared with the minimum unconfined compressive strength requirement of the rock mass for stability of cut slopes. The calculated FoS by numerical analysis indicates high susceptibility to failure of rock slopes in the selected area. The analysis highlights the risk of rock fall in the future at different locations along the highway.