Centrifugal loading method of RFPA for the failure process analysis of rock and soil structure

The fundamental principle of centrifugal tests usually applied in geotechnical engineering was introduced into rock failure process analysis(RFPA) system,so RFPA–Centrifuge was proposed.Stress analysis of RFPA-Centrifuge adopted the FEM basic arithmetic,so it was satisfied for the force equilibrium,strain consistency and nonlinear constitutive relation of rock and soil materials.RFPA-Centrifuge took the analytical function of RFPA for failure,also took into account the heterogeneous characteristics of materials at micro-and macro-scopical levels.As the proposed method was used to conduct the stability analysis of slopes of tunnel engineering which was the difficult point of geotechnical engineering,failure surface as well as the safety factor could be achieved directly without any artificial assumption on the failure surface.Based on the numerical simulation of centrifugal tests on vertical soil slopes,declining soil slopes,rock slopes with two group joints and tunnels with different shapes of sections.It was proved that RFPA-Centrifuge might obtain the failure area or slip face intuitively and realistically,and at the same time,the safety factor could be obtained.The results were close to those of physical tests and strength-reduction method with FEM.The present method could not only slide over the complex reduction rules about mechanical parameters in strength-reduction method with FEM,but also tide over the scarcity of evidence to be difficult to validate with physical tests in strength-reduction method with FEM.Therefore it is a valid numerical method for slopes in geotechnical engineering.