Analysis of the stability of slopes in fractured rock masses is not trivial and is fraught with uncertainty and risk. A DFN-DEC model (Discrete Fracture Network-Distinct Element Code) based on the MATLAB platform is developed to evaluate the stability of rock slopes with random fractures. Then, the influences of mean values of geometric characteristics (i.e., the trace length T, the dip D, and the spacing S) for both the horizontal (denoted with 1) and inclined (denoted with 2) fractures on the mean slope stability are investigated. The results indicate that the proposed DFN-DEC model based on the MATLAB platform is adequate, robust, and can generate more realistic fracture networks. By means of probabilistic analysis (i.e., Monte Carlo simulation), we can obtain a more accurate stability assessment result of fractured rock slopes. In addition, it is found that the ${\mu }_{Fs}$ (the mean of Fs) of slopes decreases with the increase in ${\mu }_{T_1}$, ${\mu }_{T_2}$ (the mean trace length of horizontal and inclined fractures, respectively) and ${\mu }_{D_1}$ (the mean dip of horizontal fractures), and increases gradually with the increase in ${\mu }_{D_2}$ (the mean dip of inclined fractures), ${\mu }_{S_1}$ and ${\mu }_{S_2}$ (the mean spacing of horizontal and inclined fractures, respectively). Furthermore, the geometric characteristics related to inclined fractures have a much greater influence on ${\mu }_{FS}$ than that related to horizontal fractures. This study can be well applied in engineering practice, e.g., preliminary evaluation of the slope stability according to the statistics of fracture geometric characteristics.

Exploring a pipeline’s response to blast vibration during tunnel excavation is critical for ensuring the safety of the pipeline. In this paper, the vibration monitoring and numerical simulation methods are used to evaluate the dynamic response of ground soil and pipelines to blasts. The attenuation law of peak particle velocity (PPV) and the distribution characteristics of peak effective stress (PES) in pipe sections under different working conditions are studied. The following findings are recorded: (1) A three-dimensional model considering in situ stress is established, and it is found the triangular equivalent load simulation blast effect method used in this paper can effectively reflect the impact of blasting on pipelines. The simulation error is controlled at 7.69%. (2) The ground PPV of each monitoring point decays continuously with the increase in horizontal and axial distance, and the cavity enlargement effect is exhibited above the excavation area. The oncoming blast side PPV of the pipe section is more significant than that behind the blast side. (3) When the blast vibration is transmitted to the pipe, there are differences in the PPV and PES distribution characteristics across the pipe cross-section. The PPV is greater in the lower part of the pipe section, while the PES value is greater in the upper part of the pipe section. The maximum PES of 1.53 MPa is significantly lower than the safety threshold (≤4.6 MPa) at the hazardous-section-monitoring point. (4) A pipeline PPV prediction model is proposed to guide subsequent blasting program development. An empirical formula for the safety criterion applicable to this study is proposed for the scientific implementation of safety assessments for subsequent construction. This safety evaluation framework can be used as a reference for similar projects.

Due to the spatial variability of hydraulic properties, probabilistic slope seepage analysis becomes necessary. This study conducts a probabilistic analysis of slope seepage under rainfall, considering the spatial variability of saturated hydraulic conductivity. Through this, both the commonly used Monte Carlo simulation method and the proposed first-order stochastic moment approach are tested and compared. The results indicate that the first-order analysis approach is effective and applicable to the study of flow processes in a slope scenario. It is also capable of obtaining statistics such as mean and variance with a high enough accuracy. Using this approach, higher variabilities in the pressure head and the fluctuation of the phreatic surface in the slope are found with a higher value of the correlation length of the saturated hydraulic conductivity. The Monte Carlo simulation is found to be time-consuming: at least 10,000 realizations are required to reach convergence, and the number of realizations needed is sensitive to the grid density. A coarser grid case requires more realizations for convergence. If the number of realizations is not enough, the results are unreliable. Compared with Monte Carlo simulation, the accuracy of the first-order stochastic moment analysis is generally satisfied when the variance and the correlation length of the saturated hydraulic conductivity are not too large. This study highlights the applicability of the proposed first-order stochastic moment analysis approach in the slope scenario.

Rainfall and fluctuations in reservoir water levels are critical external factors influencing the stability of landslides along reservoir banks. This study investigates the Yetan Primary School landslide, which serves as a representative example of a metamorphic rock landslide influenced by reservoir conditions in Shiyan City. We quantitatively investigate the evolutionary characteristics of slope seepage and stress responses by integrating GNSS field monitoring data (2021–2025) with FLAC3D numerical simulations. The analysis encompasses five distinct working conditions, including groundwater level rises of 1 m, 3 m, and 5 m, as well as periodic fluctuations in reservoir water levels ranging from 236 m to 242 m. The results indicate that rainfall is the dominant triggering factor for the landslide, with monitoring data revealing two stages of stepwise deformation that are synchronized with heavy rainfall, and a maximum average displacement rate of 0.302 mm/d. Simulation results show that when the groundwater table rises by 1 m, 3 m, and 5 m, the maximum displacement at the landslide front is 0.51 m, 1.26 m, and 2.63 m, respectively, with the plastic zone extending from the front to the rear, exhibiting a composite failure mode characterized by front traction and rear thrust. The drawdown of the reservoir water level (from 242 m to 236 m) generates outward hydrodynamic pressure, resulting in a displacement of 12.8 cm at the front, which is greater than the 2.7 cm observed during the rise. However, the impact of reservoir water alone on overall stability is limited. Landslide instability can be attributed to a coupling mechanism of ‘easily sliding metamorphic rock—hydraulic driving (water-rock softening + hydrodynamic pressure)’: rainfall triggers the composite failure of front traction and rear thrust, while fluctuations in reservoir water level primarily exacerbate deformation at the front. This study provides theoretical guidance for the early warning and prevention of similar landslides in the metamorphic rock region of northwestern Hubei Province.