Ground deformation behavior and stability prediction under static and dynamic loading conditions are of important topics in geotechnical engineering. The stress-strain relation is usually nonlinear and stiffness valies as stress increasing. In this paper, firstly introducing elasto-plastic stress-strain constitutive relation, then a elasto-plastic bilinear hardening model was verified to understand three types nonlinear calculation methods (explicit incremental method, explicit return mapping method and implicit return mapping method) under strain or stress controlled condition. Then the each algorism was applied to computer program. The calculation results were agreed well with each other. The programming process also helped students to understand the nonlinear calculation method.
