ABSTRACT
Analytical methods consist of three broad categories, which are lumped mass method, continuum mechanics model, and distinct element method respectively. Lumped mass method simplifies the motion of the sliding body as a single point with gravity. Then, particle kinematics and the principle of conversation of energy are adopted for investigating the post-failure motion. The lumped mass models (Perla et al. 1980, Hutchinson 1986) shared the same restriction that the internal deformation has not been considered. Despite the reasonable approximations to the motion of the center of gravity that provided, Evans et al. (1994) pointed
1 INTRODUCTION
Landslides which defined as the movement of a mass of rock, debris or soil down a slope are characterized by long-runout displacements and high velocity (Cruden 1991). Even far away from the origin location of the slope, significant destruction still can be brought by rapid landslides through the sliding path. However, sometimes their potential for destruction can’t be practically reduced by reinforcement of the source area (Hungr 1995). Prediction of post-failure motion is needed in the hazard assessment as an important part in case that a potential source of a landslide is detected. Therefore, engineering risk analysis emerged, especially the runout analysis which is applied to estimate the potential hazard area (Hungr 1995). In order to design protective measures, runout parameters such as the maximum displacement reached, the landslide velocity, and the distribution of the deposits should be determined through quantitative method during the runout analysis.
