Algorithm Development and Application of Double-Yield-Surface Elastoplastic Constitutive Model for Earth-Rock Materials

To enrich the constitutive models of geotechnical materials in universal commercial finite-element analysis software suites, e.g. ADINA, ABAQUS, and ANSYS, and to improve the precise simulation ability for certain geotechnical structures, Shen's double-yield-surface elastoplastic model was chosen as an example to introduce in detail the secondary development process of a constitutive model in commercial finite-element software. The stress integration algorithms were modified, and the superiority of the algorithms was investigated by comparing the numerical simulation with triaxial test data for coarse-grained soil. Further, an ideal concrete-face rockfill dam was used to validate the accuracy of the secondary development process and the algorithms. Finally, the numerical simulation of a practical concrete-face rockfill dam was conducted. The results indicate that the stress integration algorithms and the secondary development process presented in this study are universal and can be employed for the secondary development of double or multi-yield-surface elastoplastic models in universal finite-element analysis software.