Shallow landslide prediction in the Serra do Mar, São Paulo, Brazil

Abstract

Abstract.Various methods are currently used in order to predict shallow landslides within the catchment scale. Among them, physically based models present advantages associated with the physical description of processes by means of mathematical equations. The main objective of this research is the prediction of shallow landslides using TRIGRS model, in a pilot catchment located at Serra do Mar mountain range, São Paulo State, southeastern Brazil. Susceptibility scenarios have been simulated taking into account different mechanical and hydrological values. These scenarios were analysed based on a landslide scars map from the January 1985 event, upon which two indexes were applied: Scars Concentration (SC -ratio between the number of cells with scars, in each class, and the total number of cells with scars within the catchment) and Landslide Potential (LP -ratio between the number of cells with scars, in each class, and the total number of cells in that same class). The results showed a significant agreement between the simulated scenarios and the scar's map. In unstable areas (SF≤1), the SC values exceeded 50% in all scenarios. Based on the results, the use of this model should be considered an important tool for shallow landslide prediction, especially in areas where mechanical and hydrological properties of the materials are not well known.

Sensitivity analysis and calibration of a dynamic physically based slope stability model

“…For the background infiltration rate describing a steady-state infiltration component, constant values (e.g. Kim et al, 2013;Vieira et al, 2010) or multiples of K s (e.g. Park et al, 2013) were used.…”

“…Regolith depth maps are prepared as a function of the slope angle (Salciarini et al, 2006), using a geomorphologically indexed model (Zizioli et al, 2013), using a spline interpolation of direct measurements (Kim et al, 2013) and with spatially constant values (Park et al, 2013;Vieira et al, 2010). The initial depth of the water table d wi (positive in downward direction) is assumed to be either at the regolith-bedrock interface (Kim et al, 2013;Park et al, 2013;Vieira et al, 2010) or at a depth relative to it (Salciarini et al, 2006;Zizioli et al, 2013). For the background infiltration rate describing a steady-state infiltration component, constant values (e.g.…”

Condicionantes Morfológicos e Geológicos dos Escorregamentos Rasos na Bacia do Rio Santo Antônio, Caraguatatuba/SP

“…Características morfológicas como curvatura e ângulo das encostas associadas aos parâmetros litológicos e estruturais podem contribuir para a identificação de classes mais propícias à ocorrência de processos morfodinâmicos como escorregamentos, permitindo inferir os fatores condicionantes dos mesmos (SIDLE et al;1985;PACHAURI E PANT, 1992;VIEIRA et al, 2010). Desta maneira, o objetivo deste trabalho foi analisar a influência dos parâmetros geológicos e morfológicos na ocorrência de escorregamentos na bacia do rio Santo Antônio no município de Caraguatatuba / SP.…”

Landslide and slope stability evaluation in the historical town of Kruja, Albania

“…These soils in arid seasons (summer-autumn) have better geotechnical properties than in wet seasons (winter-spring). From many authors (Guzzetti, et al, 2003;Vieira et al, 2010) and from our investigations carried out for the last 20 years (Muceku, 2008), the majority of slope movements occur during the wet seasons (heavy rain). For that is very important to emphasize that this area is much affected by rainfall.…”