Stability Analysis of a 90 m Super-High Disturbed Open-Pit Slope in Nepal Under Strong Earthquakes and Continuous Rainfall

A large number of earthquake disaster sites have shown that earthquakes are only one of the causes of landslides on high slopes. Sometimes a landslide is caused by a combination of multiple factors. Taking a 90 m super-high disturbed open-pit slope on a mountain highway in Nepal as an example， this study used Slide software to analyze the stability of the slope under different working conditions （dry， rainfall， and earthquake）. The main research focused on the evolution of the seepage field， the dynamic variation of pore water pressure， and the influence of rainfall infiltration of different durations on slope stability. The results showed that： 1） Both earthquakes and rainstorms were detrimental to slope stability， among which the simulation results under the “slope surface water” working condition were conservative， which could easily lead to design redundancy. 2） Continuous rainfall caused the infiltrated rainwater to migrate to the adjacent slope surface， which easily formed surface runoff， resulting in a linear downward trend in slope stability. 3） After the application of systematic anchors combined with drainage measures， the slope stability was significantly improved， verifying the support concept of “solid feet and strong waist， drainage first”. Based on on-site conditions， construction suggestions suitable for high slopes in Nepal’s mountainous areas were proposed.