Abstract:

The deformation modulus of fault rock mass is an important parameter to denote its mechanical characteristic, and it is obviously related to the environment. A large scale hydropower project was taken as an example to analyze the influence of deformation modulus of fault rock masses on dam base stability based on site test and theory and 3D-numerical analysis. Result indicates that if the deformation modulus of fault rock mass increases from 0.6 Gpa to 4.0 GPa, the horizontal displacement at key point in the dam will decrease 0.544-0.846 mm, the vertical displacement at key point in the dam will decrease 1.190-2.232 mm and the maximal tensile stress at key point in the dam will decrease 0.06 MPa because of the increase in the deformation modulus of fault rock mass after impoundment of hydropower station and without influence of water infiltration, which is advantageous to stability of dam base.

Key words: engineering geology, rock mass of fault zone, deformation modulus, stability of dam base, three-dimensional FEM