Theory　and　experiments　show　that　the　general　twin-shear　stress　criterion　can　represent　the　shear　strength　of　soil　and　rock　more　accurately　than　the　conventional　Mohr-Coulomb　criterion.　However,　there　is　no　constitutive　model　based　on　the　general　twin-shear　stress　criterion　in　the　existing　large-scale　finite　element　software.　The　smoothed　function　proposed　by　Gudehus-Argyr　is　essentially　a　corner　model　of　the　general　twin-shear　stress　criterion　for　removing　the　sharp　edges　of　the　Mohr-Coulomb　criterion.　On　the　basis　of　studying　the　corner　model,　a　plastic　potential　function　was　established,　and　the　expressions　of　all　flow　vectors　were　deduced.　In　line　with　the　complete　implicit　backward　Euler　integration　algorithm,　the　corresponding　user　material　subroutine　UMAT　was　programed　using　the　Fortran　language　in　ABAQUS.　The　UMAT　was　applied　in　numerically　modeling　the　conventional　triaxial　compression　test,　the　uniaxial　tension　test　and　true　axial　test　as　well　as　in　analyzing　the　stability　of　an　embankment,　and　the　modeling　results　were　compared　with　those　by　the　embedded　Mohr-Coulomb　model　in　ABAQUS.　It　is　shown　that　the　numerical　implementation　approach　of　the　corner　model　is　completely　correct　and　reliable,　and　is　beneficial　to　the　practical　application　of　the　general　twin-　shear　stress　criterion　to　overcome　the　conservative　flaw　that　the　conventional　Mohr-Coulomb　model　is　prone　to.　©　2021,　Science　Press.　All　right　reserved.