Abstract:A general constitutive theoretical framework of saturated pore-fracture media need be formulated to guide constitutive modeling. Firstly,based on the mixture theory and nested way,the energy balance equation of saturated pore-fracture media is obtained. Secondly,according to the thermodynamic work conjugation behaviors,the strain and stress state variables of the constitutive equation for saturated pore-fracture media are determined. Thirdly, based on the assumption of local equilibrium of thermodynamics, the general free energy potential constitutive equations are obtained for saturated pore-fracture media. Finally,deriving from the general free energy potential constitutive equations,an isotropic linear elastic equation is obtained taking into account the coupling of pore and fracture skeleton deformations. When the pore and fracture skeleton deformations are uncoupled, the equation is degenerated into Khalili’s linear elastic equation. The researches show that,the solid phase strain can be decomposed into the sum of fracture skeleton strain, pore skeleton strain and volumetric strain of solid material in the case of small strain;When the mixture homogenous response principle is valid and the fluid material constitutive model is the same as the single fluid one, the fracture skeleton strain,pore skeleton strain,volumetric strain of solid material,volumetric strain of fluid material in fractures and volumetric strain of fluid material in pores uniquely determine the effective stress of fractured media, effective stress of pore media,real pressure of solid material,fracture pressure and pore pressure,respectively. A linear elastic constitutive relation can be achieved when the free energy function is a quadratic function of state variables.