This article performs groups of shaking table tests to study the dynamic damage characteristics of the slope that is composed with inclined bedrock, upper overburden soil layer, and weak soil interlayer. The prototype is of the entrance slope of the Mount Zheduo tunnel, which is located in the mountains of the western Sichuan Plateau in China. The test model is designed based on the similarity theory. The peak ground acceleration (PGA) amplification coefficient, Fourier transform, and transfer function theory are employed to analyze the test results. The results before slope failure indicate that the PGA amplification coefficient of both the overburden layer and the weak interlayer increases as the excitation intensity increases. At the same time, the dynamic response of weak interlayer is amplified on low-frequency wave excitation while that is impaired when high-frequency seismic waves dominate. When the slope is damaged, the slope undergoes large shear deformation: the whole overburden layer slides along the weak interlayer, and the PGA amplification coefficient of the weak interlayer sharply decreases. The frequency response function indicates that the vibration relationship between the upper part of the weak interlayer and the slope surface is very close, and the slope surface vibration may be mainly affected by the vibration in the upper part of the weak interlayer, which reflects the early predictability in the failure symptoms of the slope.

Grouting reinforcement technology gradually has been widely used to repair the subgrade settlement diseases, but the current single application of discrete element software or finite element software cannot effectively simulate the grouting process. Therefore, one new method is put forward in the research of grouting based on the CFD-DEM coupling principle. And then, one typical subgrade section in the ShanghaiNanjing intercity railway is used to simulate the grouting process and diffusion mechanism of slurry from microlevel. Based on the results of site survey, some findings are shown as follows: First, the new method is feasible which integrates the favorable aspects of discrete elements, finite elements, and boundary elements. Second, the greater the grouting pressure, the greater the influence range of grouting, and it shows six petals shape. When the grouting pressure is small, the grouting generally shows penetration or extrusion grouting, and its influence range is small. When the grouting pressure is large enough, it is characterized by splitting grouting, and the influence range of grouting is getting larger and larger. Third, the growth rates of influence range gradually increase with the increasement of grouting pressures, and the reasonable selection of grouting pressures is very important.