Landslide Susceptibility Mapping of Highway Slopes, Using Stability Analyses and GIS Methods
A.M.L. Craig, O. Augusto Filho
Soils and Rocks, São Paulo, 43(1): 71-84, January-March, 2020 | PDF
The study presented in this paper aims to map landslide susceptibility on highway slopes and adjacent areas, using an approach based on stability analysis with deterministic methods considering semi-regional and detail work scales. The infinite slope method in a Geographic Information System (GIS) environment and a 1:10,000 scale topographic base (elevation intervals of 5 m) were used in the stability analysis at the semi-regional scale. Geological-geotechnical sections surveyed in the field with measuring tape and inclinometer (1:100 scale with 0.5 m vertical slope intervals) and the Bishop Simplified method were used in the detail scale. The geological-geotechnical materials present in the studied area are residual soils (sandstones, basalt and diabase), alluvial deposits and landfills. The slopes and marginal areas of the highway more susceptible to landslides were mapped based on quantitative models of analysis, reducing the subjectivity of the mapping. Limitations of the infinite slope method related to its physical-mathematical model were identified and analyzed. The approach used was efficient even considering the limitations of the infinite slope analysis method and the representativeness of the geomechanical parameters used in the stability analyses.
Submitted on March 26, 2019; Final Acceptance on January 29, 2020; Discussion open until August 31, 2020.