In this study, a large-scale model test was performed to investigate the effect of the single-row and double-row micropiles on the landside stabilization. For two different testing configuration settings, the bending moment along the micropiles, failure mode, and force condition were captured and compared. It is found that the landslide thrust on piles was distributed in a triangular shape. The piles in the front row carried greater pressure than the piles in the rear row. The resistance of the sliding body behind the pile was distributed in a parabolic shape, and mainly concentrated on the middle of the pile. The piles were destroyed due to the combined shearing and bending impact applied near the slipping surface. The boundary of the failure zone was from the position of two times the pile diameter under the slipping surface to the position of two and a half times the pile diameter above the slipping surface. Under the action of the landslide, each row of piles deformed at the same time. The capability of landslide stabilization for double-row piles was better than that of a single-row pile. The sections of the pile above slide surface were mainly subjected to negative bending moments and were distributed mainly within the pile length range of one-third of the anti-sliding section above the sliding surface. The pile body of the embedded section located in the range of ten times the pile diameter below the sliding surface was subjected to a positive bending moment.

Loess landslides represent a prevalent and severe type of geological disaster in the Loess Plateau and its surrounding regions. Their frequency and intensity are notably exacerbated under rainfall conditions. This study focuses on investigating the destabilization mechanism of loess landslides induced by rainfall preferential infiltration on the northern slope of the Xining Haihu Bridge. A combination of on-site monitoring, soil property testing, and numerical simulations was employed. The findings reveal that during rainfall events, water rapidly infiltrates into the deep soil layer through pre-existing preferential pathways, such as cracks. This alters the internal water distribution within the soil, leading to localized slope saturation. The subsequent increase in pore water pressure and substantial reduction in soil shear strength emerge as critical factors in triggering loess landslides. Additionally, numerical simulation models were utilized to analyze slope stability under varying rainfall scenarios. The analysis identifies key factors influencing the stability of loess landslides, namely rainfall intensity, duration, and the position and depth of cracks. Furthermore, this study innovatively integrates quantitative analysis of rainfall-induced preferential infiltration with dynamic simulations of landslide stability. This approach offers a more robust theoretical foundation for predicting, assessing, and mitigating loess landslides. By quantifying the relationship between landslide stability and rainfall infiltration patterns, the study provides vital technical support for early warning systems, disaster prevention strategies, and the optimization of engineering measures aimed at addressing loess landslide hazards.

Vacuum preloading is one of the popular methods improving the engineering properties of slurry ground with high water content. Commonly, the efficiency of vacuum preloading gradually decreased due to the clogging of prefabricated vertical drains (PVDs) and the low‐vacuum transmission rate inside slurry. Thus, the calcium‐based flocculants were used to accelerate the dewater capacity and enhance the soil strength during vacuum preloading. This paper performed a series of model tests to investigate the effect of calcium‐based flocculants on the efficiency of vacuum preloading. It is found that the vacuum transmission rate was significantly improved by flocculants in comparison with raw slurry. Accordingly, the after‐treatment undrained shear strength increased with the vacuum pressure, while the after‐treatment water showed a decrease trend. This suggests that the increase of vacuum transmission rate inside the slurry due to the calcium‐based flocculants was the main reason for the improvement of efficiency of vacuum preloading. In addition, there existed an optimal flocculants amount, where the vacuum pressure increased with flocculants’ amount up to this threshold value, followed by a decrease in vacuum pressure. This means that, at lower flocculants amount, the increase in soil flocs due to flocculation effect tended to refine the net‐frame structure and water flow path, leading to an increase in the efficiency of vacuum preloading. When exceeding the optimal amount, overdosage of flocculants resulted in the clogging of PVDs due to large cemented soil particles, reducing the vacuum transmission rate inside the slurry. Hence, the after‐treatment soil strength decreased with flocculants’ amount when it is higher than the optimal value.

A large‐scale model test on the interaction between a micropile group and a landslide was conducted, to investigate the effect of micropiles on the landsides prevention. The bearing mechanism, force condition, and failure mode of a micropile group for reinforcing landslide were analyzed in detail. The results showed that the thrust force over micropiles induced by landslide showed a trapezoidal distribution, with a higher Earth pressure near the sliding surface. The resistance from the sliding body behind the pile behaved in a parabolically trend. Meanwhile, the resistance force from the sliding bed was distributed unevenly along the height direction, with a higher resistance force near the sliding surface behind the pile. When a landslide occurred, micropiles were subjected to an increase in loading and displacement, eventually to the failure state. The load‐bearing sections of the micropiles were all subjected to negative bending moments, with larger bending moments within the half length of pile range near the sliding surface. The maximum negative bending moment occurred at the height of seven times the diameter of the pile above the sliding surface. The damage mode along each row of micropiles was almost the same, showing a damage area within the range of three times the diameter of the pile above and below the sliding surface. The failure of micropile induced by landslides was mainly due to a combination effect of bending and shearing near the sliding surface.

This paper presents a case history of observed performance of highway embankment over soft marine clay in Wenzhou, China. During the embankment construction, the changes of ground settlement, ground displacement, and lateral displacement of subsoil with the construction time were monitored and analyzed. The monitoring results indicate that the ground settlement and lateral displacement of subsoil account for about 75% in the process of embankment construction. The measured maximum values of ground settlement, ground displacement, and lateral displacement of subsoil are 37.88 mm, 21.50 mm, and 23.56 mm, respectively. After the completion of the embankment construction, the settlement gradually tended to be stable. It is suggested that the monitoring data of settlement and displacement of embankment are smaller than the design requirements, and the embankment stability is also ensured.