The　simulation　of　shear　band　evolution　path　is　of　vital　importance　in　prevention　of　geotechnical　disaster.　During　shear　band　evolution,　the　strain　localization　condition　at　all　the　shear　band　tips　as　well　as　the　force　equilibrium　should　be　obeyed,　which　is　proposed　to　be　treated　as　the　nonlinear　complementarity　problem　(NCP).　Since　the　partial　derivative　of　this　NCP　is　hard　to　solve,　instead　of　the　Newton　method,　the　projection　contraction　algorithm　(PCA)　is　invoked　to　solve　the　NCP　to　yield　the　shear　band　evolution　step　length.　To　reduce　the　computational　expense,　the　meshes　of　improved　numerical　manifold　(INMM)　are　used　to　discretize　the　domain　of　the　soil-rock　mixture　(SRM).　Based　on　the　displacement-controlled　method　(DCM),　the　plasticity　and　contact　nonlinearities　are　solved　in　a　unified　way.　The　proposed　procedure　could　naturally　simulate　the　growth　of　shear　band,　allowing　the　shear　band　tip　to　stop　anywhere,　alleviating　the　mesh　dependence.　Some　types　of　slope　examples　are　solved　to　test　the　performance　of　the　proposed　approach.