简介：BasedongoverningequationsofsaturatedporousmediaandLiapunov'sstabilityhere,onsetconditionsmatrixofporousmediausedbysolidstressandTerzaghi'seffectivestressconstitutivedescriptionunderseepageflowstate,arepresented,whichhavedifferentformswithdifferentrepresentationofthesolidphase,matrixorskeleton,constitutivemodelofporousmedia.Themaindifferencerelateswithhowtodescribetheinteractionbetweensolidphaseandliquidphaseinconstitutivemodel.ThederivedonsetconditionofstrainlocalizationunderTerzaghi'seffectivestressdescriptioncanbeusedtointerpretdifferentfailuretypes,pipingeffect,landslidesandmudflows,bymeansofthetypeandthemagnituderatioofrelativemovementbetweensolidphaseandliquidphase.Exampleshereilluminatetheonsetconditionofhowtowork.