Static and dynamic analysis of a landslide

Abstract

Slope failure is a recurrent phenomenon in hilly regions. It is hazardous because of the accompanying rapid mass movement of soil and rock mass. To alleviate the damage caused by landslide, slope-stability analyses and stabilization techniques require in-depth understanding and appraisal of the process that govern the failure behaviour of slopes. Once the instability behaviour is understood, remedial measures such as retaining walls, rock bolts, anchoring, etc., can be recommended to stabilize the slope. This article deals with a comparative study used for the analysis of the stability of slopes of Amiyan area, near Kathgodam, Nainital, Uttarakhand assuming that the rock mass follow the Mohr–Coulomb failure criterion under static and dynamic loading conditions. The area constantly experiences local as well as regional slides along the river bank. A field study was carried out in the landslide area to collect the representative samples to determine the various physio-mechanical properties of rock as well as debris samples. These properties have been used as input parameters after converting it into the rockmass properties using a joint weakening coefficient for the numerical simulation. The computed deformations and the stress distributions, along the failure surface, have been compared with the field measurements/observation and found to be in good agreement. The global factor of safety (FOS) calculated by finite difference, finite element and dynamic analysis was found to be 1.57, 1.144 and 0.84, respectively. This indicates that the slope is critically stable in case of any small local/global disturbance which may further reduce the FOS and cause failure.