Starting from the unloading and reloading hysteretic curves of the Hardin-Drnevich model

different expressions of dissipation function are formulated in order to reconsider the energy dissipation mechanism of H-D model based on the thermodynamics principle. Two kinds of different translation rules of the back stress are assumed: one is the straight line; the other is the skeleton curve; and then the yield function expressions in the dissipative stress space are obtained by using of Ziegler’s orthogonality condition. Moreover

adding the shift stresses to the dissipative stresses

the form of the yield condition in the true stress space is deduced. The plotting of yield curve in true stress space indicates that the form of the shear yield curve is straight line for the two different shift rules when the shear strain is below the threshold value. However

when the shear strain is above the threshold value

the shear yield curves appear bending.