Loess structure is more important mechanical properties of loess besides its particle size

density and humidity. Based on the theory of comprehensive structure potential

we made a synthesis of the existing structural parameters and their evolution

and structural parameter can be of two types: initial structural parameter and the process of structural parameter. Structural parameter tends to satisfy both the basic physical property of soil and its evolution under the condition of stress and moisture. Based on existing problem of structural parameters and their evolution

structure index is used to describe initial structure

and stress ratio structure parameter is used to describe the process of structure. The relationship between stress ratio structural parameter and comprehensive strain is studied. Finally

a mathematical model that can reflect the attenuation evolution of soil structure under the condition of initial stress and moisture is established. Theoretical analysis and triaxial test show that the model can avoid the influence of confining pressure under the condition of triaxial tests on initial structure

and it can consider the influence of body strain and shear strain under the process of stress and moisture. The model can more accurately reflect the damage evolution of loess.