Tool NameSAFETYFACTOR
Tool ID0
Library IDta_slope_stability
Version1.0
Author(s)A. Günther (c) 2012

Description

This tool computes a slope stability (expressed as a factor-of-safety) raster according to the traditional infinite slope model theory (see cf Selby, 1993) The resulting raster represents the ratio of resisting forces/driving forces (fs) on a potential shear plane with fs lesser 1 unstable, fs greater 1 stable. Except for a slope raster (in radians), all input variables can be specified either globally or distributed (through grids). The tool creates a continuous fs raster (values above 10 are truncated), and a binary stability grid with nodata = stable, 1 = unstable (optional).

Parameters

NameTypeIdentifierDescriptionConstraints
Input
Slope grid (rad)grid, inputAA slope angle grid (in radíans)
Min thickness grid (m) grid, input, optionalBminA grid representing minimum cell layer thicknesses to potential shear plane (in meters)
Max thickness grid (m) grid, input, optionalBmaxA grid representing maximum cell layer thicknesses to potential shear plane (in meters)
Min saturation grid (-) grid, input, optionalCminA grid representing minimum cell relative water saturation of layer (dimensionless)
Max saturation grid (-) grid, input, optionalCmaxA grid representing maximum cell relative water saturation of layer (dimensionless)
Min friction grid (degree) grid, input, optionalDminA grid representing minimum cell frictional shear strength of layer (in degrees)
Max friction grid (degree) grid, input, optionalDmaxA grid representing maximum cell frictional shear strength of layer (in degrees)
Min density grid (g/cm3)grid, input, optionalEminA grid representing minimum cell bulk density of layer (in grams per cubiccentimeters)
Max density grid (g/cm3)grid, input, optionalEmaxA grid representing maximum cell bulk density of layer (in grams per cubiccentimeters)
Min cohesion grid (MPa) grid, input, optionalFminA grid representing minimum cell layer cohesion (in Megapascals)
Max cohesion grid (MPa) grid, input, optionalFmaxA grid representing maximum cell layer cohesion (in Megapascals)
Output
FS valuesgrid, outputGResulting factor-of-safety (-) grid
FS classesgrid, output, optionalHResulting stability (0/1) grid
Options
Min global thickness (m)floating point numberfBminConstant value if no raster setDefault: 1.000000
Max global thickness (m)floating point numberfBmaxConstant value if no raster setDefault: 1.000000
Min global saturation (-)floating point numberfCminConstant value if no raster setDefault: 0.000000
Max global saturation (-)floating point numberfCmaxConstant value if no raster setDefault: 0.000000
Min global friction (degree)floating point numberfDminConstant value if no raster setDefault: 33.000000
Max global friction (degree)floating point numberfDmaxConstant value if no raster setDefault: 33.000000
Min global density (g/cm3)floating point numberfEminConstant value if no raster setDefault: 1.600000
Max global density (g/cm3)floating point numberfEmaxConstant value if no raster setDefault: 1.600000
Min global cohesion (MPa)floating point numberfFminConstant value if no raster setDefault: 0.000000
Max global cohesion (MPa)floating point numberfFmaxConstant value if no raster setDefault: 0.000000
Parameter sampling runsinteger numberfINumber of sampling cyclesDefault: 1