Heavy metal ions, such as Cd, Hg, Pb, and As, tend to persist in soil without natural degradation and can be absorbed by crops, leading to the accumulation of agricultural products that pose a significant threat to human health. However, the development of a rapid and efficient technique for identifying heavy metals in agricultural products is essential to ensure health and safety. With the knowledge of the extent of damage caused by heavy metals, it becomes imperative to detect the presence of cadmium in the soil, water, and the environment. This study introduces a novel plate approach for quick and precise colorimetric detection of cadmium ions using the Cd(II)-Chrome Azurol S CAS-2,2 '-dipyridyl dipy-Cetylpyridinium Bromide CPB quaternary complex. Our innovative method has shown that at a reaction solution pH of 11, the optimal concentration ratio is CAS (5 x 10-3 M): dipy (0.1 M): CPB (1.0 x 10-3 M) = 4 mL: 1 mL: 1 mL. The most significant fading alert was observed when the ethylenediaminetetraacetic acid (EDTA) chelator was added dropwise to the CAS detection plate, indicating strong chelation of Cd by EDTA. This laboratory-based study established a foundation for future applications in real environmental sample analysis.

The laboratory experiment is an effective tool for the rapid assessment of the unsaturated soil slopes instability induced by extreme weather events. However, traditional experimental methods for unsaturated soils, including the measurement of the soil-water characteristic curve (SWCC), soil hydraulic conductivity function (SHCF), shear strength envelope, etc., are time-consuming. To overcome this limitation, a rapid testing strategy is proposed. In the experimental design, the water saturation level is selected as the control variable instead of the suction level. In the suction measurement, the suction monitoring method is adopted instead of the suction control method, allowing for simultaneous testing of multiple soil samples. The proposed rapid testing strategy is applied to measure the soil hydro-mechanical properties over a wide suction/saturation range. The results demonstrate that: (1) only 3-4 samples and 2-5 days are in need in the measurement of SWCC; (2) 7 days is enough to determine a complete permeability function; (3) only 3 samples and 3-7 days are in need in the measurement of the shear strength envelope; (4) pore size/water distribution measurement technique is fast and recommended as a beneficial supplement to traditional test methods for unsaturated soils. Our findings suggest that by employing these proposed rapid testing methods, the measurement of pivotal properties for unsaturated soils can be accomplished within one week, thus significantly reducing the temporal and financial costs associated with experiments. The findings provide a reliable experimental approach for the rapid risk assessment of geological disasters induced by extreme climatic events.

Recent earthquakes have highlighted the importance of earthquake ground motion recordings and rapid visual inspections (RVSs) of damaged buildings to assess the earthquake impact on the building inventory, prepare recovery plans, and provide valuable findings that could contribute to the preparedness ahead of future earthquake events. The effect of strong earthquake ground motions on the building stock is controlled by a range of interconnected factors. These include the intensity of ground motion, the effects of local soil conditions, the structural design, reinforcement and material properties, as well as the quality control during construction, among others. However, it is important to acknowledge that the earthquake ground motions recorded are dependent on local variables, such as the soil type and potential operational issues. Such an example is the major M6.4 earthquake in Durr & euml;s, Albania, in November 2019, the most significant in the region in the past four decades. The strong ground motion recorded at the sole Durr & euml;s accelerometric station was interrupted due to a power outage. As a result, the recorded accelerograms (with a PGA of 0.192 g) require thorough analysis and evaluation before they can be reliably used in assessing damage of existing structures. The current paper presents a framework for evaluating the incomplete record to ensure that the strong ground motion pulse is captured in the acceleration series. The latter is achieved by analyzing and comparing the amplitude and frequency contents of the recorded motion against ground motion accelerograms from areas with similar seismotectonic features. Ground motion recordings from stations that have soil conditions resembling those of the Durr & euml;s region are used, ensuring that the analysis is relevant to the specific study area. Next, the disrupted ground motion recording is evaluated by comparing the damage of post-earthquake inspected buildings with the results of advanced numerical analysis for the case of a typical 12-storey and a 5-storey building. The effects of pounding, the presence of infills, soil-structure interaction (SSI), and multiple failure modes are taken into consideration. Results indicate that despite the incomplete data, the seismic record retains the essential strong ground motion features and can be used for further studies. The numerical simulations aligned well with observed damage from rapid visual inspections, verifying the record's integrity. The findings show that factors such as soil-structure interaction, infill panels, and pounding effects significantly influenced building performance. The study concludes that the Durr & euml;s record, though incomplete, is reliable for seismic assessment and can aid future risk studies in the region.

The composite rapid soil stabilizer (CRSS) is a newly developed material for rapid curing of sludge with fast setting, fast hardening, and high strength properties. CRSS was used to solidify the sludge, and the durability test of the solidified sludge under the action of sulfate erosion was carried out to analyze the influence of erosion time and Na2SO4 and MgSO4 concentration on the physical and mechanical properties of the solidified sludge. The research results showed that as the erosion time increased, the mass of soaked samples increased gradually. Additionally, the strength of samples soaked in clear water continued to rise, while the strength of samples soaked in sulfate increased first and then decreased. After 112 days of erosion, the higher the concentration of SO42-, the greater the mass of the soaked sample and the lower the strength. At the same concentration, the mass of the soaked sample with MgSO4 was the largest, but the strength was the lowest. Under the action of sulfate attack, the soaked samples produced a large number of expansive products, and the cumulative pore volume first decreased and then increased. The microstructure of the MgSO4-soaked samples suffered the most damage due to the double corrosion of Mg2+ and SO42-. Based on the macroscopic and microscopic test results, the microscopic evolution mechanism of the durability of solidified sludge under Na2SO4 and MgSO4 erosion environments was revealed. The solidified sludge with CRSS has good sulfate resistance durability, which lays a theoretical foundation for the engineering application of CRSS.

Rapid and long-runout landslides characterized by their high speed, long distance mobility, and huge capacity and volume would pose significant threats to infrastructure and life safety. In this study, a rapid and long-runout landslide that occurred in the Bingda village of the northeastern Tibetan Plateau, which was triggered by heavy rainfall in June 2017, was preliminarily investigated. On the basis of detailed field surveys, high-resolution satellite imagery analysis, and laboratory tests, the morphological and sedimentological features of the landslide were described, and the formation mechanism of hummocky landforms and its insight into the extraordinary movement of the Bingda landslide was deduced. The field investigation and satellite imagery analysis showed that there were nearly 200 hummocks, mostly with normal circular bases and with a height of similar to 0.1 m-7.5 m, distributed in the transfer and accumulation areas of the landslide. The height and number density of the hummocks decreased away from the transfer area to the accumulation area and displayed higher heights at the outer bends of the gully channel than that at the inner bends of it. The characteristics of the spatial distribution and the composition of hummocks indicated that significant generation and dissipation of pore-water pressure within the loose and saturated silty clay layer in the runout path was the most probable reason for the formation of hummocky landforms. This study also provided insights into the hypermobility mechanisms of the Bingda landslide, suggesting that this landslide began with the sliding failure of the weathered colluvium in the source area, and then the landslide debris traveled into the channel and impacted sudden undrained loading and rapid shearing to the underlying silty clay layers in the gully. These processes generated pore-water pressure and reduced the effective stress within the soil particles, resulting in a decrease in the frictional resistance in the substrate, finally facilitating the rapid and long-runout movement of the landslide.

Seabed foundations consisting of interbedded layers of saturated soft clay and sand deposited during the Quaternary period are widely distributed in the coastal areas of Southeastern China. These soil foundations are prone to significant settlement under seismic loading. The study of the seismic dynamic response characteristics of saturated foundations with interbedded soft clay-sand and the development of rapid prediction models are essential for controlling settlement and ensuring the service safety of marine structures. A total of 4000 sets of seabed foundation models are randomly generated, with layers of saturated soft clay and sand and with a random distribution of layer thickness and burial depth. The mechanical behavior of saturated soft clay is described using the Soft Clay model based on the boundary surface theory, and the generalized elastoplastic constitutive model PZIII is used to characterize the mechanical behavior of sandy soil. The finite element platform FssiCAS is employed for a computational analysis to study the characteristics of seismic subsidence in saturated seabed foundations with interbedded soft clay-sand. A machine learning model is implemented based on the Random Forest algorithm, in which 3200 sets of numerical simulation results are used for model training, and 800 sets are used for validating the model's reliability. The results show that under seismic excitation, the pore water pressure within the saturated seabed foundation with interbedded soft clay-sand accumulates, effective stress decreases, and the seabed foundation softens, to a certain extent. During the post-seismic consolidation phase, significant settlement of the seabed foundation occurs. The fast prediction model based on the Random Forest algorithm could reliably predict the settlement characteristics of submarine foundations. This research provides a new technological avenue for the rapid prediction of the seismic settlement of submarine foundations, which could be of use in engineering design, assessment, and prediction.

Fusarium crown rot (FCR) is a significant global issue in wheat production. Planting resistant cultivars is the most effective strategy for mitigating FCR damage. However, breeding for FCR resistance is challenged by the lack of a reliable and high-throughput method for rapid and accurate assessment of numerous genotypes. This study evaluated FCR resistance in 50 wheat genotypes using the common soil-based method. None of the genotypes were immune or highly resistant and only 6.0% (three genotypes) showed moderate resistance at the seedling stage. Resistant and susceptible genotypes were then selected for preliminary experiments. A rapid water-culture method for assessing FCR resistance in wheat seedlings was developed. Seedlings were planted in petri dishes and inoculated by spraying conidial suspensions. This new method, which takes 15 days (about 50% of the time required for soil-based methods), requires minimal space and eliminates variability associated with soil or potting mixes. The disease index correlation between water-culture and soil-based methods was significant (p < 0.01) with a correlation coefficient of 0.901. The resistance evaluation consistency among 50 genotypes using both methods was 94.0%, indicating high reproducibility and strong agreement with soil-based results. Therefore, this new method should be a valuable tool for initial screening of FCR-resistant germplasms from numerous genotypes in breeding programs.

The present study proposes a rapid visual screening methodology for multi-hazard vulnerability assessment (termed as MH-RVS) of reinforced concrete (RC) buildings in the Indian Himalayan region considering earthquakes, debris flow, debris flood, and soil subsidence. An extensive field survey of 1200 buildings was conducted in three hill towns situated in the Northwestern Indian Himalayan region to identify prevalent multi-hazard vulnerability attributes. The presented MH-RVS methodology is statistically developed based on the information obtained from the current field survey and existing post-hazard reconnaissance studies. The proposed methodology effectively addresses the concern of underpredicting the expected damage states of RC buildings situated in hilly regions subjected to multi-hazard scenarios when they are assessed using RVS methodologies of seismic vulnerability assessment. Further, a simplified MH-RVS form is developed to collect field data and conveniently segregate the RC buildings based on their expected damage state under multi-hazard scenarios involving earthquakes, debris flow, debris flood, and soil subsidence. Stakeholders and decision-makers can use the proposed MH-RVS methodology to assess the perceived vulnerability of RC buildings in the Indian Himalayan region and devise timely strategies for structural strengthening and risk mitigation.

Debris flows are a dynamic and hazardous geological phenomenon, as by definition, debris flows are rapid, gravity-driven flows of saturated materials that often contain a mixture of water, rock, soil, and organic matter. They are highly destructive and occur in steep channels, posing a significant threat to infrastructure and human life. The dynamics of debris flows are complex due to their non-Newtonian behaviour and varying sediment-water interactions, making accurate modelling essential for risk mitigation and emergency planning. This paper reports and discusses the results of numerical simulations of back analyses aimed at studying the reconstruction of a real rapid debris flow. The selected test case is the event that occurred on 12 and 16 March 2021 along the Rio Sonno channel, a tributary of the Liri River, following the landslide event of Rendinara (Municipality of Morino, Abruzzo Region, Italy). There are significant flow sources in the area, fed by a highly fractured carbonaceous aquifer that extends immediately upslope of the detachment zone. The continuous flow influences the saturation level in the fine-grained sediments and favours the triggering of the debris flow. This phenomenon was simulated using the commercial RAMMS code, and the rheological model selected was Voellmy fluid friction. The modelling approaches used in this research are valid tools to estimate the volumes of materials involved in the flow-feeding process and for the purpose of possible mitigation works (debris flow-type dams, weirs, flow diversion, etc.).

This study focused on applying numerical simulations to assess damaged areas caused by debris flows, employing the LS-RAPID program while emphasizing the importance of terrain information. Terrain information used in the numerical simulation included a 1:5000 digital terrain map and a digital surface model using an unmanned aerial vehicle. Quantification of the amount of soil that collapsed from the road embankment slope, which is the source of the debris flow, facilitated the computation of the debris flow that closely resembled real-world conditions. In particular, incorporating the high-resolution digital surface model (DSM) with 3-cm topographic information resulted in an interpretation of the actual soil flow damage range that is similar to actual observations of the digital elevation model (DEM), which had 1-m grid topographic information. This difference arises from DSM as it reflects the information of low hills downstream. The range of damage changed as the direction of the debris flow changed because of the low hill. Many variables need adjustment for the accuracy of debris flow numerical simulation. However, the direction and range of flow vary greatly depending on topographic information, highlighting the necessity of applying high-resolution terrain information. The results of debris flow simulations with high-resolution terrain information are expected to improve accuracy and help prepare risk or damage maps.