tutorial-landslide-initiation

TutorialLandslidesInitiationModelling,UniSa-USGSTutorialactivity“Usingaphysically-basedmodelforslopestabilityanalysisoverlargeareas”SabatinoCuomoUniversityofSalerno,ItalyUNIVERSITÁDISALERNODIPARTIMENTODIINGEGNERIACIVILEincooperationwith:UNITEDSTATESGEOLOGICALSURVEYLARAMSchool2012-2ndAsiaCourse12–23November2012,Chengdu(CHINA):UncoupledInfiltration/StabilitymodelTutorialLandslidesInitiationModelling,UniSa-USGSTheoreticalBasis:Run-offModelTutorialLandslidesInitiationModelling,UniSa-USGSTheoreticalBasis:SlopeStabilityModelcossintan),(tantanZtZcFOSSWfZWNSfrsrwhere:S=depth-averagedsoilunitweighttoaccountforthelowerunitweightofpartiallysaturatedsoilabovethewatertable.FactorofSafetytanfwafafuuucExtentedMohr-CoulombCriterionuafctanfeRigid–perfectlyplasticconstitutivemodelInfiniteSlopeModelTutorialLandslidesInitiationModelling,UniSa-USGSProgramOperationsTutorialLandslidesInitiationModelling,UniSa-USGSPreviousapplicationsBaumR.,GodtJ.,SavageW.Z.(2010).Estimatingthetimingandlocationofshallowrainfall‐inducedlandslidesusingamodelfortransient,unsaturatedinfiltration.Journalofgeophysicalresearch,115,doi:10.1029/2009jf001321.Seattle,Washington(USA)TutorialLandslidesInitiationModelling,UniSa-USGSPreviousapplicationsSorbino,G.,Sica,C.,Cascini,L.,2009.Susceptibilityanalysisofshallowlandslidessourceareasusingphysicallybasedmodels.NaturalHazards,53,313-332.Sarno-Quindici(Italy)TutorialLandslidesInitiationModelling,UniSa-USGSTUTORIAL-UniSaInput-DTM(dem1.grid,dem1.asc)-Slopeangle(dem1_sl.grid,dem1_sl.asc)-Flowdirection(dem1_dir.grid,dem1_dir.asc)-Topoindexvalues-Rainfalldata(2scenarios)-MechanicalsoilpropertiesOutput-Slopesafetymap(foreachscenario)TutorialLandslidesInitiationModelling,UniSa-USGSRainfalldata:Intensity-durationvsT(returnperiod)tutorialTRIGRS-rainfalldataI(mm/h)T(years)d(hours)2510205010020050010000.15356.7075.6089.93106.88132.29153.80176.61206.59230.05129.0238.7046.0454.7167.7278.7390.41105.75117.77315.8121.0825.0829.8136.9042.8949.2657.6264.16610.3413.7816.4019.4824.1228.0432.2037.6641.94126.658.8610.5412.5315.5118.0320.7124.2226.97h(mm)244.245.656.727.999.8911.5013.2015.4517.20scen1191.8482.693.594.275.076.287.308.389.8110.92scen2402.4722.062.753.273.884.815.596.427.518.36961.702.272.703.213.984.625.316.216.921201.471.962.332.773.433.994.585.365.972400.931.241.481.752.172.522.903.393.783600.710.951.131.341.661.932.222.592.894800.590.780.931.111.371.601.832.142.397200.450.600.710.851.051.221.401.641.8310000.360.480.570.680.840.981.131.321.47I(m/s)d(s)scen12.22E-0686400scen22.33E-0617280011010010000.11101001000I(mm/h)d(h)251020501002005001000scen1scen2T(years)TutorialLandslidesInitiationModelling,UniSa-USGSFromfile“tr_in.txt”Nameofproject(upto255characters)TRIGRS,version2.0.07k,TutorialTRIGRS–LARAM-Asia-2011imax,row,col,nwf,tx,nmax(txsuddivisioneperiododipioggiaperilcalcolo,nmaxeq.6,pag.9)166582716490279796,1,30nzs,mmax,nper,zmin,uww,t,zones(nper,periodidipioggia,tfininsecondi)3,100,1,0.001,9.8e3,86400,1zmax,depth,rizero,Min_Slope_Angle(degrees)(conilsegno-leggeilrelativogrid)2.001,2.001,1.0e-9,0.zone,1Cohesion(Pa),phi(°),uws(Pa),diffus(m2/s),K-sat(m/s),Theta-sat,Theta-res,Alpha(conilsegno-adalphasaturated)mechproperties5e+0336.,1.6e+04,1.0e-05,5.0e-06,0.45,0.05,-0.5cri(1),cri(2),...,cri(nper)(m/s,402mmin48ore)rainfallintensity(m/s)2.22e-6capt(1),capt(2),...,capt(n),capt(n+1)(48ore)rainfallduration(s)0,86400….Numberoftimestosaveoutputgrids1Timesofoutputgrids86400TutorialLandslidesInitiationModelling,UniSa-USGSTutorialonLandslideinitiation•ConsiderScenario1andScenario2fortherainfallintensity–durationvalues•ComputethewaterpressureheadsandFactorofSafetyforeachscenario(runningtheTRIGRScode),•Contourtheresults(withILWISgiscode),•Discusstheresults.Somenotes:•toreadtheTRIGRSresults:•openILWIS,•MenuFile/Import/Map/Outputname“...”•MenuFile/Open“…”•Modifyscaleandcolours•adequatechoicetorepresentyourresults,EmptyScalebarNEWSFactorofSafety0-0.70.7-11-1.11.1-33-11NoDataWaterpressurehead(m)0-0.0860.086-0.1730.173-0.2590.259-0.3460.346-0.4320.432-0.5180.518-0.6050.605-0.6910.691-0.777NoData