This study aims to extend the scope of cutting plane algorithm for calculating the constitutive equations in the bounding surface model. Moreover

a new algorithm should inherit the simple and efficient framework in the classical elastoplasticity model. The maximum limit of incremental step was employed to propose a modified cutting plane method by using an adaptive sub-stepping algorithm. This method was also applied to an improved bounding surface model for structured clay. Experiments were conducted on Shanghai clay to validate the bounding surface model using the modified method. The validation of the modified method was proven through obtained results. According to parameters of Shanghai clay

numerical studies were also carried out to simulate undrained triaxial tests

undrained simple shear tests

undrained triaxial cyclic tests and oedometer test

respectively. The maximum limit of the incremental step was further determined. Finally

an undrained single shear test was simulated under the large strain step condition by using the modified method. As a result

the accuracy and stability of the modified cutting plane method were verified.