A Numerical Study on Controlling Parameters for Runout Distance of Landslides

Abstract

AbstractNumbers of uncertainties are involved in slope stability analysis. In particular, when a slope fails, uncertainty of parameters of the slope will cause the variability of runout distance of sliding mass which decides the consequence triggered by landslides. In general, slope geometry parameters and residual strengths parameters are highly close to the runout distance of landslides. This paper aims to investigate the effect of residual strength parameters and initial geometry parameters on runout distance of landslides via material point method. To clearly indicate relation of runout distance and these parameters for different soil slopes, three kinds of slopes, i.e., slopes in single soil layer, slopes in weaker upper soil layer and stronger lower soil layer and slopes in stronger upper soil layer and weaker lower soil layer are studied. For the first and third kinds of slopes, it is found that runout distance has a good negative exponential law with residual strength parameters and has a significant linear increase trend with geometry parameters. For the second kind of slope, the decrease trend of runout distance with residual strength parameters is faster; The increase trend of the runout distance with slope gradient can be indicated well via sigmoid curve; There is also a good linear increase relation of the runout distance and slope elevation. Additionally, the relation between runout distance and slope elevation obtained via MPM in this paper is consistent with that based on the empirical method. The conclusions can provide reference for assessment and management of landslides risk.KeywordsLandslidesControlling parametersRunout distanceRelationMaterial point method