Over the past few decades, engineering research has increasingly focused on the reliability assessment of transport infrastructures and their critical components when faced with multiple natural hazards. This trend stems from recognizing the substantial direct and indirect economic losses associated with infrastructure damage and the resulting downtime. The increasing frequency of intense hazard occurrences, as a consequence of climate change, coupled with the time-intensive nature of post-event bridge inspections, highlights the need for an efficient approach to assess bridge fragility to hazards that occur either as single abrupt events or in compounds, i.e., multiple hazard perturbations or combined incremental deterioration. This approach should account for the order of hazards and the accumulation of damage to bridge components. Within this context, we introduce an analytical method for evaluating the fragility of bridges affected by independent or multiple successive and independent natural hazards. The proposed method is demonstrated through a case study in which a riverine bridge is evaluated considering different sequences of hazards. Initially, the fragility of the bridge under individual hazards, such as earthquakes or floods, is calculated. Subsequently, multi-hazard fragility curves are constructed to capture the combined effects of these events. This approach is a comprehensive method for generating fragility curves for bridges, considering all structural components involved in the resisting system of the structure. These curves are based on a detailed estimation of thresholds for different limit states, encompassing multiple failure modes and accounting for soil-structure interaction (SSI) effects. The method employs a probabilistic framework to manage uncertainties in both the demand on the structure and its capacity to withstand single hazards. The framework is extended to include scenarios involving multiple hazards that occur separately or in series, emphasizing how cumulative damage influences the overall bridge fragility. The findings indicate a significant increase in the probability of damage for all the limit states examined, underscoring the importance of considering the cumulative effect of multiple hazards in the fragility analysis of bridges. The fragility models can be used in life-cycle risk assessment of aging bridges exposed to multiple hazards to inform decision-making and prioritization of investments for risk mitigation and climate adaptation.

Geohazards such as slope failures and retaining wall collapses have been observed during thawing season, typically in early spring. These geohazards are often attributed to changes in the engineering properties of soil through changes in soil phase with moisture condition. This study investigates the impact of freezing and thawing on soil stiffness by addressing shear wave velocity (Vs) and compressional wave velocity (Vp). An experimental testing program with a temperature control system for freezing and thawing was prepared, and a series of bender and piezo disk element tests were conducted. The changes in Vs and Vp were evaluated across different phases: unfrozen to frozen; frozen to thawed; and unfrozen to thawed. Results indicated different patterns of changes in Vs and Vp during these transitions. Vs showed an 8% to 19% decrease for fully saturated soil after thawing, suggesting higher vulnerability to shear failure-related geohazards in thawing condition. Vp showed no notable change after thawing compared to initial unfrozen condition. Based on the test results in this study, correlation models for Vs and Vp with changes in soil phase of unfrozen, frozen, and thawed conditions were established. From computed tomography (CT) image analysis, it was shown that the decrease in Vs was attributed to changes in bulk volume and microscopic soil structure.

The Pernote landslide event in the Ramban area on April 25, 2024, caused significant damage and displaced many residents. Preliminary investigations identified the landslide as a massive, complex debris slide and flow, primarily involving overburden materials such as mud, silt, clay, and rock fragments. The slide was characterized by several rotational slip planes and debris flow channels. The severity of the event was attributed to explicit geological conditions, including fault and thrust zones, loose consolidated and deformed rocks from the Murree Formation, and thick deposits of Quaternary sediments exceeding similar to 20 m. Heavy antecedent rainfall (100-175 mm) from April 20th to 24th saturated the debris and soil cover, triggering the landslide on the steep slopes (angle > 45 degrees). The total displacement was approximately 40 m, with a depth of about similar to 12 m. The slide zone extended from the crown to the toe, reaching up to the River Chenab, covering approximately 1250 m. The Pernote landslide was not entirely unexpected, as early signs of movement-such as deep fissures, ground cracks, and bulges-were observed as early as 2021. Temporal analysis of high-resolution Google Earth images from 2012 to 2022 supports these observations, revealing signs like old landslide scars, ground cracks, and ongoing landslide activity. Additionally, during the past decade, significant changes in vegetation cover and a 19.2% increase in built-up areas were noted. These findings highlight the importance of monitoring early surface indications as warning signs for effective landslide mitigation, preparedness, and public awareness to prevent loss of life and infrastructure in future events.

Landslides are one of the most hazardous geological processes due to their difficult-to-predict nature and destructive effects, often leading to significant loss of life, infrastructure damage, and environmental disruption. In the Southern Andes of Chile, landslides are particularly frequent and destructive due to a combination of factors, including high seismic activity, steep topography, and the presence of weak, unconsolidated pyroclastic soils. Unfortunately, the geomechanical control of landslide initiation in the Southern Andes is still poorly understood, creating a significant source of uncertainty in developing accurate landslide susceptibility or risk models. This study evaluates the geological and geotechnical factors that control the generation of landslides in pyroclastic soils using in situ data, laboratory analysis and remote sensing approaches. The study area covers the surroundings of the Mocho-Choshuenco Volcanic Complex (MCVC), one of the most explosive volcanoes in the Southern Andes. The results show that the landslides are placed on slopes covered by multiple explosive eruptions that include a period of more than 12 ka. Landslide activity is related to pyroclastic soils with significant weathering and halloysite content. In addition, the geotechnical characteristics show very light soils, with highwater retention capacity, which is vital to induce mechanical instability. The detected deformation may be associated with seasonal precipitation that would increase the pore water pressure and reduce the shear strength of the soil, promoting slow-moving landslides. The geological and geotechnical characteristics of the soils suggests that slow-moving landslides would be extended to a large part of the Southern Andes. Finally, this study contributes to improving hazard assessment to mitigate the impact of landslides on the population, infrastructures and natural resources in the Southern Andes.

Recycling paper sludge waste (PSW) into inexpensive sheets for applications in household interiors, construction, and footwear is a sustainable approach to resource utilisation and pollution reduction. A flexible recycled sheet (FRS) in board form was developed using cellulosic-based PSW from the paper industry and a styrene-butadiene rubber (SBR) binder. Various SBR concentrations were tested to determine the optimal amount for superior mechanical properties. The produced FRS was characterised using Fourier transform infrared spectroscopy, thermogravimetric analysis, high-resolution scanning electron microscopy, and energy-dispersive X-ray spectroscopy. FRS made with 1000 g of PSW:300 ml of SBR exhibited enhanced mechanical properties, including tensile strength (62.32 +/- 0.51 MPa), elongation at break (51.99 +/- 0.94%), tearing strength (17.76 +/- 0.45 N/mm), and flexibility (6.98 +/- 0.24%). A biodegradation study, conducted per ASTM D 5988-03, assessed environmental impact by measuring carbon-to-CO2 conversion in soil over 90 days. All FRS samples showed similar degradation within the first 30 days, with FRS 5 degrading significantly faster thereafter due to its higher cellulose and hemicellulose content. This highlights the potential of PSW-based FRS as an environmentally friendly and mechanically robust material for diverse applications.

This study presents a novel investigation into the seismic response of micropiles through shaking table tests, diverging from the predominant reliance on numerical analyses in assessing micropiles in liquefiable sites. Three models of shaking table tests were conducted using Iai scaling rules for physical modelling in 1-g conditions. The investigation reveals a significant dependency of micropile efficiency on the frequency of input motions. During the 2 Hz test, the entire model experienced liquefaction; however, in the 3 Hz test, there was a remarkable 29% reduction in excess pore water pressure. Additionally, the study explores the impacts of varying distances between micropiles and examines how liquefaction influences the induced peak accelerations at different depths within the soil media. Notably, recorded accelerations on the surface decreased by up to 76% in the free field tests during liquefaction. This comprehensive exploration advances our understanding of micropile behaviour under seismic conditions, offering valuable insights for soil improvement projects.

Different slope geohazards have different causal mechanisms. This study aims to propose a method to investigate the decision-making mechanisms for the susceptibility of different slope geohazards. The study includes a geospatial dataset consisting of 1203 historical slope geohazard units, including slope creeps, shallow slides, rockfalls and debris flows, and 584 non-geohazard units, and 22 initial condition factors. Following a 7:3 ratio, the data were randomly divided into a test set and a training set, and an ensemble SMOTE-RF-SHAP model was constructed. The performance and generalization ability of the model were evaluated by confusion matrix and the receiver operating characteristic (ROC) for the four types of geohazards. The decision-making mechanism of different geohazards was then identified and investigated using the Shapley additive explanations (SHAP) model. The results show that the hybrid optimization improves the overall accuracy of the model from 0.486 to 0.831, with significant improvements in the prediction accuracy for all four types of slope geohazards, as well as reductions in misclassification and omission rates. Furthermore, this study reveals that the main influencing factors and spatiotemporal distribution of different slope geohazards exhibit high similarity, while the impacts of individual factors and different factor values on different slope geohazards demonstrate significant differences. For example, prolonged continuous rainfall can erode rock masses and lead to slope creep, increased rainfall may trigger shallow mountain landslides, and sudden surface runoff can even cause debris flows. These findings have important practical implications for slope geohazards risk management. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

On 18 December 2023, a Ms 6.2 earthquake struck the Jishishan area in Northwest China, located at the border of the Qinghai-Tibet and Loess Plateau. The earthquake triggered shallow loess landslides, small rock failures, and soil cracks, mainly along hilly gullies and cut slopes at the edges of terraced fields. A rare large-scale flowslide also occurred in irrigated farmland. These seismic landslides and collapses blocked roads, buried farmland, damaged houses, and resulted in many casualties. Field investigations revealed that these geological hazards were concentrated around cultivated land. Consequently, cultivated land was introduced as an engineering geological zoning factor into the seismic geological hazard risk assessment for Jishishan area. The Newmark cumulative displacement model was refined by incorporating lithological uncertainties via the Monte Carlo method. Comparative analysis of coseismic geohazards with and without considering cultivated land suggests that, in loess-covered areas with cultivation activities, the consideration of the disturbed characteristics of soils provides a more accurate probabilistic risk assessment of seismic geohazards. Human cultivation and irrigation activities affect the physical properties of surface soil, the terraced fields around earthquake prone areas have a risk of earthquake-induced geological hazards. This study may offer valuable insights for hazard prevention and mitigation in high fortification intensity loess covered areas.

Hydrologically-induced landslides are ubiquitous natural hazards in the Himalayas, posing severe threat to human life and infrastructure. Yet, landslide assessment in the Himalayas is extremely challenging partly due to complex and drastically changing climate conditions. Here we establish a mechanistic hydromechanical landslide modeling framework that incorporates the impacts of key water fluxes and stocks on landslide triggering and risk evolution in mountain systems, accounting for potential climate change conditions for the period 1991-2100. In the drainage basin of the largest river in the northern Himalayas- the Yarlung Zangbo River Basin (YZRB), we estimate that rainfall, glacier/snow melt and permafrost thaw contribute similar to 38.4%, 28.8%, and 32.8% to landslides, respectively, for the period 1991-2019. Future climate change will likely exacerbate landslide triggering primarily due to increasing rainfall, whereas the contribution of glacier/snow melt decreases owing to deglaciation and snow cover loss. The total Gross Domestic Productivity risk is projected to increase continuously throughout the 21st century, while the risk to population shows a general declining trend. The results yield novel insights into the climatic controls on landslide evolution and provide useful guidance for disaster risk management and resilience building under future climate change in the Himalayas.

Bisphenols (BPs) are ubiquitous environmental endocrine disruptors that cause various human health hazards and pollute water, soil, and the atmosphere to varying degrees. Although various studies have investigated the pollution characteristics and health hazards of BPs in different media, a systematic review of BPs in the broader environmental context is still lacking. This study highlights the pollution characteristics, detection methods, and risk assessment status of BPs by combining relevant studies from both domestic and international sources, and their environmental distribution characteristics are summarized. The results show that BP pollution is a widespread and complex global phenomenon. Bisphenol A (BPA) remains the predominant component of BPs, which can damage the nervous and reproductive systems. At present, high-performance liquid chromatography-tandem mass spectrometry, high-performance liquid chromatography, and liquid chromatography-tandem mass spectrometry are the main detection methods used for BPs. BPs can also damage the reproductive system, leading to germ cell apoptosis and ovarian damage. Future research should focus on expanding the BP testing repertoire, advancing rapid detection techniques, elucidating toxic mechanisms, conducting comprehensive safety assessments, and developing systematic health risk assessment methods. These efforts will provide a scientific foundation for preventing and controlling emerging pollutants.