Stability Analysis of Landslides using Catastrophe Theory

Abstract

Most of the landslides are catastrophic, discontinuous and complex in nature to realize. It is a challenging aspect to reduce the risk of landslides, which is one of the common natural hazards during monsoon season. Limit equilibrium methods depend on shear strength parameters and for soil kinematics is not admissible in stability analysis of slopes. But, in case of landslide failures, it would be more appropriate if displacement of the soil mass along the shear plane is incorporated in stability analysis. In the present study, a displacement-based model is proposed and analyzed using cusp catastrophe theory, which is a mathematical theory deals better with geomorphic processes, such as landslides. The constitutive behavior of soil is characterized along the planar shear plane and comprised of two different soil medium i.e., elasto-brittle medium and strain softening medium. Therefore, the slope instability mechanism, is based on the soil stiffness along the shear plane, unlike based on the shear parameters. The stiffness of the soil on shear plane depends on shear modulus, length of the soil medium and displacement ratio. The factor of safety of the slope is determined and differentiates whether the landslide is a rapid moving landslide or slow-moving landslide. By varying different variables, the parametric analysis is done to determine the factor of safety.