The finite element method (FEM) and discrete element method (DEM) have been widely applied to analyze the deformation and failure processes of embankment slopes. Although both methods can produce promising results, the choice between them has long remained unresolved. In this study, a failure case of a granite residual soil (GRS) embankment was analyzed. FEM and DEM models were established to simulate the instability process of this embankment slope, and the applicability of both methods to GRS embankments was then evaluated. The main conclusions are as follows: (1) Geotechnical parameters of GRS were determined through laboratory testing, and FEM and DEM models were developed to reproduce the deformation and failure behavior of the embankment slope subjected to rainfall and vehicle loading. (2) Similar rainfall infiltration patterns were obtained from both FEM and DEM simulations; however, significant differences in deformation were observed. The FEM-predicted deformation was 0.075 m after rainfall, indicating that the embankment remained stable. In contrast, the DEM-predicted deformation reached 1.4 m, indicating that the embankment slope had already become unstable. (3) The DEM simulation closely reproduced the failure of the GRS embankment slope observed in the field. It realistically captures the process of particle disintegration in GRS caused by rainfall infiltration, as well as the subsequent slope collapse. Therefore, DEM can be regarded as the most appropriate approach for modeling the instability of GRS embankment slopes.

This paper presents an analytical solution for near-field cylindrical P-wave scattering by a circular tunnel. A comprehensive elastic–slip interface model is incorporated to capture localized discontinuous deformations and frictional sliding. Employing the wave function expansion method and Graf’s addition theorem, the dynamic stress concentration factor (DSCF) of both soft and stiff linings is systematically investigated. The results reveal that near-field wavefront curvature severely amplifies stress concentration on the illuminated side, degenerating into a plane-wave response only when the dimensionless source distance exceeds 50. Furthermore, within the parameter range considered, the imperfect interface exhibits a dual “flexible barrier” effect heavily influenced by impedance matching: it tends to act as a seismic isolator that reduces the DSCF for stiff linings, but can weaken boundary confinement and exacerbate stress concentration for soft linings. These findings provide crucial theoretical insights for the blast-resistant design of underground structures.

Few studies have focused on the deformation of ultra-deep circular foundation pits under the combined effects of dewatering and recharge. Therefore, a case of an ultra-deep circular foundation pit in a soft soil area was selected to investigate the mechanisms of groundwater variation induced by dewatering and recharge during excavation, and the resulting ground surface and diaphragm wall deformation. The main conclusions are as follows: (1) The model was validated against field measurements, showing good agreement in magnitude and variation trends for both ground settlement and diaphragm wall deformation. (2) With increasing dewatering rate, pore water pressure at the dewatering wells gradually decreased, forming more pronounced drawdown funnels. The reduction in pore water pressure increased soil effective stress, expanded the high-stress zone, and induced ground settlement and lateral displacement of the diaphragm wall, intensifying overall pit deformation. (3) With increasing recharge rate, pore water pressure around the recharge wells gradually increased, forming localized high-pressure zones. Ground surface heave occurred due to buoyancy from the expanded saturated soil zone, while lateral displacement of the diaphragm wall was simultaneously amplified. The affected zone expanded with higher recharge rates, enhancing overall soil deformation around the pit.