Based on the results from a series of drained plane strain compression (PSC) tests along different stress path and isotropic loadingunloading triaxial tests on Shanghai fine sand,the modified plastic work shearvolumetric double hardening function is proposed,which is independent of stress history and stress path.Then an elastoplastic doublehardening constitutive model for Shanghai fine sand is formulated on the basis of the modified plastic work hardening function.The comparison between calculation results from the numerical method incorporating the proposed constitutive model and experimental data shows that the proposed constitutive model can reflect the deformation and strength behavior on Shanghai fine sand reasonably.