Stability Analysis Of Rock Slope Based On Failure Approach Index

Up until now, several kinds of methods have been developed to analyze the slope stability, including limit equilibrium method, limit analysis, strength reduction method, etc. The limit equilibrium method is used widely in slope stability analysis both in domestic and international. The strength reduction method, which is based on numerical calculation, has a rapid development with the development of the computer science. Based on the other researchers'achievements, with the rockmass damage fracture theory, a new variable called FAI(failure approach index) is attained. FAI is based on rockmass damage strain and stress at a certain seconds, it is used to evaluate the stability of rockmass slope. The main contents are as follows:(1) Three different rockmass constitutive equations in damage fracture theories are deduced. Linking with constitutive equations and rockmass characteristic points, basic characters of rockmass are analysed on macro and meso level. And the time-dependent characteristics of rockmass damage fracture are researched.(2) Based on the researching of rockmass characteristic points, a new variable called FAI is attained. FAI takes the strain and stress at a certain second as variable, it ranges between 0 and 1.When it is bigger, the rockmass is much near failure.(3) FLAC3D can be used to simulate large deformation, and it can accurately answer the computation of rock and soil materials. With the help of FLAC3D, two examples of FAI is showed in this article to solve the problems in experiment and project application. It is proved that FAI can be used to evaluate the rockmass stability state, through the graph drawing of the failure region units, we can determine the failure trend and the failure face, etc.(4) As FAI is advanced, this article detailed introduced the use of FAI in rockmass slope stability analysis. It contains slip surface searching and safety factor calculation. Result shows that the slip surface and the safety factor are coincide with the results calculated by FLAC3D. It proved that the FAI can be used in the slope stability analysis.