Assessment of rainfall-induced landslide reactivation through hypo-plastic material model

Landslides are recognized as one of the major hazards, reflected through large material and human loss throughout the world. They can be triggered by anthropogenic, but also due to a natural and/or climatic factors. Rainfalls are noted as one of the most important natural triggers for landslides re-activation, while the positive trend in the climate change shown recently, implies that this type of weather-related hazards would be even more frequently prevalent in future. Thus, rainfall induced landslide arises large interest among the professionals that are working in this field recently, and is main concern of this research paper. The long-term stability, as well as the landslide reactivation susceptibility due to rainfall, of one well documented slope is going to be assessed in time, through FE analysis in program package PLAXIS. In the model two different hydrologic scenarios measured on the aforementioned location, are going to be analysed; average annual precipitation data for the period between 1961-1996 and average annual precipitation data for the most recent period between 2005-2014. The soil behaviour in time is represented with the non-linear hypoplastic material model, which is considered that will provide the most reliable results for the deformations, taking into account the strain-softening behaviour. One of the main interests of this paper is the slope failure mechanism in time, the spatial position of the failure plane due to the rainfall infiltration and pore water fluctuation, as a result of changes in the meteorologic data. Furthermore, this paper provides a comprehensive analysis of the laboratory tests needed for the hypo-plastic material model.