Long-term geotechnical slope deterioration, influenced by weathering and meteorological factors, presents stability challenges to infrastructure. Wetting and drying cycles lead to pore water pressure variations, causing deformations and slope failure. Studies on glacial tills which investigate deterioration in geotechnical slopes focus on variables like pore water pressure, soil water retention, compaction, freeze-thaw cycles and cracking. This research conducts a preliminary assessment of an Irish glacial till-cut slope, establishing a data-driven foundation for long-term slope behaviour studies. Data analysis, geospatial modelling and numerical simulations were performed on a cut slope in Castleblayney (Ireland), considering short-term/undrained and long-term/drained conditions. FLAC/Slope and Scoops3D were used for 2D and 3D slope stability analyses, applying the First-Order Second Moment (FOSM) probabilistic approach to assess how minor soil property changes affect slope stability, including long-term deterioration scenarios. The study underscores the importance of precise instrument placement within Irish glacial till geotechnical cut slopes, particularly at the uppermost part where shallow and deep failures coincide under long-term and short-term scenarios. This informs strategic instrument positioning for accurate slope deterioration investigations. This research lays the groundwork for understanding mechanisms driving geotechnical slope deterioration and provides insights for future studies on geotechnical asset deterioration models in Irish glacial tills.

The rapid development of rural regions, the mountainous landscape, and frequent subtropical-typhoon-related rainfall have collectively contributed to a high incidence of cut slope-induced landslides in the coastal areas of eastern China. Despite the escalating risk, there has been a noticeable absence of comprehensive hazard assessments and targeted management measures for private housing and road construction in these rural environments. This paper introduces a novel approach for mitigating such risks by employing a susceptibility evaluation framework grounded in machine learning and uncertainty methods, combined with a double-index rainfall intensity-duration (I-D) threshold model. The proposed Intelligent Slope Prevention System operates through a sequential four-step process: (i) Site-specific landslide susceptibility is assessed through cut slope feature investigations and the use of three machine learning algorithms, namely, Support Vector Machine (SVM), Random Forest (RF), and Artificial Neural Network (ANN); (ii) the double-index model calculates rainfall thresholds, accounting for both prolonged continuous rainfall and short-term heavy rainfall events; (iii) the integration of rainfall thresholds with susceptibility assessments allows for the categorization of hazard levels; and (iv) tailored management strategies are deployed for data collection and early warning issuance. The study demonstrates that the SVM achieved the highest prediction accuracy across soil, rock-soil mixed, and rock slopes. The double-index model further enhanced the system's performance by predicting all 20 rainfall-induced landslides, with 15 of them falling under high or very high warning levels. An empirical evaluation during a heavy rainfall event on 29th June 2021 confirmed the system's effectiveness in identifying high-hazard areas and issuing timely warnings, thus significantly mitigating potential damage. Implemented in the coastal mountain basins of eastern China, the Intelligent Slope Prevention System leverages the gathered knowledge to manage and regulate slope hazards effectively, thereby enhancing the safety of both residential and infrastructural assets.

Icing in cut slopes is a serious risk to transportation safety in cold regions. Research on the occurrence process and mechanism of icing is a prerequisite for proposing effective management measures. We took the cut slopes of the K162 of the Beihei Highway as the research object. We used a combination of field investigation, geological exploration, monitoring, and simulation to study and analyze the power source, occurrence process, and triggering mechanism of icing in cut slopes. The results show that the geologic type of this cut slope is a mudstone-sandstone interaction stratum. Abundant shallow groundwater is the source of water for icing. The excavation of cut slopes extends the effect of negative temperatures on groundwater flow during the winter period. The process of ice formation in cut slopes can be described as follows: As the environmental temperature drops, the surface soil begins to freeze, resulting in a gradual narrowing of the water channel; then, the groundwater flow is blocked, so that the internal pressure begins to rise. When the internal pressure of the pressurized groundwater exceeds the strength of the frozen soil, groundwater overflows from the sandstone layer to the surface, forming icing. The high pore water pressure inside the cut slope is the precursor for the occurrence of icing. The dynamic pressure of the pore water pressure is the main driving force for the formation of icing in cut slopes. The obstruction of the water channel due to ground freezing is the triggering condition for ice formation in cut slopes.

PurposeThe ecological damage caused by cut slopes in mountainous areas is serious, and ecological restoration is urgently needed. In this context, outside soil spray seeding (OSSS) combined with a frame beam is often used in mountainous areas of southwestern China. The aims of this study were (1) to determine the differences in soil organic carbon (SOC) and its fractions of cut slopes under different restoration methods and (2) to explore the factors influencing SOC and its fractions of cut slopes in this study area.Materials and methodsTwo cut slopes restored by different restoration methods (framed slope, using OSSS combined with a frame beam, FS; rimless slope, unassisted restoration, RS) were selected, and a nearby naturally developed slope that had not been cut was used as a reference (NS). The SOC, SOC fractions, and related soil parameters were investigated.Results and discussionCompared with RS, the available phosphorus, urease activity, amylase activity, microbial biomass carbon (MBC), and light-fraction organic carbon (LFOC) levels of FS were significantly higher. However, there were no significant differences in pH, bulk density, available nitrogen, saccharase activity, SOC, particulate organic carbon (POC), and readily oxidizable organic carbon (ROC) between FS and RS. Notably, the MBC contents of FS and RS were higher compared to that of NS, which may be due to the fact that the deep soil was exposed to the air after stripping the surface soil of the cut slopes, which facilitated the growth of aerobic microorganisms. The dissolved organic carbon (DOC) content of FS was lower than that of RS, most likely because of the higher MBC content of FS compared with RS. The main soil parameters influencing soil SOC and its fractions were available nitrogen, available phosphorus, and bulk density.ConclusionsDespite the implementation of ecological restoration measures, the SOC and its fractions of the cut slope did not fully recover, and there was a gap between the soil quality of FS and NS. Further research is needed to determine whether OSSS combined with frame beams is an effective ecological restoration method for cut slopes in this area.