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This study establishes a theoretical framework for analyzing the lateral oscillation of marine pipe piles. The additional mass model is introduced herein to consider the inertial fluctuation effect of the soil plug. Analytical mathematical methods are used to determine the complex impedance variation of the pile over a range of frequency effects. An investigation is performed to determine how the presence of soil plugs changes the lateral complex stiffness and natural frequency of pipe piles. Additionally, comparisons of the applicability of the plane strain model and continuous medium model have been conducted to enable the easy use of the theoretical model. The main conclusions can be drawn as (1) if the fluctuation inertia effect of the soil plug is not taken into consideration, the dynamic active length and the dynamic stiffness of the pipe pile will be underestimated; (2) for the soft soil, the plane strain model may give rise to substantial calculation errors attributed to them regardless of the vertical continuity of the soil, nevertheless, the calculation error decreases rapidly with the increase of soil shear modulus and vibration frequency. [ABSTRACT FROM AUTHOR]

The soil–water characteristic curve (SWCC) describes the relationship between water content and soil suction, which is an important tool for determining the engineering properties of unsaturated soil. By measuring SWCC through vapor equilibrium technique, which could obtain soil suction up to 309 MPa, this paper explored the influences of the soil type and salt content on SWCC of saline soil. The experimental results illustrate that fine‐grained saline soil had a good water‐holding capacity, which had a higher air entry value and slower dehydrate rate. The study also brings out the observation that salt had negligible influence on soil suction and parameters effecting SWCC in low suction range; however, this effects was slight until it disappeared with the suction increasing. [ABSTRACT FROM AUTHOR]

Soil structure is a standard component of pedon descriptions collected to characterize the nature and function of soils as a natural body. Soil structure is an important indicator of soil development and a predictor of water, air, and root movement throughout the profile. However, inconsistencies exist within the current standardized methodologies used to describe soil structure in the field, making soil structure data difficult to use and often confusing to students encountering these concepts for the first time. Therefore, we propose an updated method of soil structure description to add an interpretive component that clearly distinguishes geogenic, pedogenic, and human‐induced structures. This method employs terminology that communicates both observable morphology and the mechanism of formation. The updated method herein differentiates three classes of structure: (a) geogenic structural formation (GS), (b) natural pedological structural formation (current nomenclature), and (c) significant human‐induced structure changes from natural pedological structure. This updated approach improves the documentation of scientifically relevant soil morphology and communicates the processes involved in the formation of all forms of soil structure. As a result, this change eases description challenges around soil structure and interpretations common in soil science classes, including soil judging. Core Ideas: Soil structure falls into three categories: (1) natural pedogenic; (2) geogenic; and (3) human‐induced.Soil education would be improved by distinguishing formation factors for soil unit breaks.Experienced field soil scientists easily recognize these differences, but those just learning do not. [ABSTRACT FROM AUTHOR]

One of the most popular soil conservation campaigns is based on the USDA Natural Resource Conservation Service's Soil Health Principles (NRCS‐SHPs). The NRCS‐SHP program identifies four principles—maximize presence of living roots, minimize disturbance, maximize soil cover, and maximize biodiversity—with the underlying assumption that the more principles one follows, the greater improvements in soil health. Despite the popularity of the NRCS‐SHPs, this underlying assumption has not been rigorously tested. To do so, we used nine long‐term experiments all located in central Iowa, but with varying degree of NRCS‐SHP adoption, to determine if greater adoption increases three slow‐changing (maximum water holding capacity, bulk density [BD], and soil organic carbon) and three dynamic (microbial biomass carbon [MBC], potentially mineralizable carbon [PMC], and permanganate oxidizable carbon [POXC]) soil health indicators. We regressed these indicators with a soil health principle score that can scale soil management based on adoption of the NRCS‐SHPs. Of the slow‐changing soil properties, increased adoption of NRCS‐SHPs only decreased soil BD (R2 = 0.22, p = 0.024). On the other hand, increased adoption of NRCS‐SHPs strongly predicted increases in both MBC and PMC and across two sampling dates (R2 > 0.23, p < 0.015); POXC, however, did not increase with greater adoption. The consistent increases in MBC and PMC with greater adoption of NRCS‐SHPs supports their usefulness as sensitive indicators of positive soil health change. Our study provides scientific evidence to support the NRCS‐SHPs concept, improving its usefulness as an extension campaign, and stands as a step toward evidence‐based soil conservation. Core Ideas: The NRCS Soil Health Principles (NRCS‐SHPs) combined effects stand untested.We used a novel metric and six soil health indicators across nine long‐term experiments in Iowa to test it.Soil organic carbon, permanganate oxidizable carbon, and water holding capacity did not relate to NRCS‐SHPs.Bulk density decreased with greater adoption of NRCS‐SHPs.Microbial biomass and potentially mineralizable carbon increased with NRCS‐SHPs adoption. [ABSTRACT FROM AUTHOR]

Pb-contaminated soil poses inherent risks for the spread of antibiotic resistance genes (ARGs). However, few reports have investigated the distribution of lead resistance genes (LRGs), particularly their role in ARGs dynamics during Pb-contaminated soil remediation. This study explored the mechanisms driving ARGs variation under different remediation strategies. The results indicated that an increase in the total abundance of ARGs after applying montmorillonite (Imvite), the composite remediation agents of MgO and Ca(H2PO4)2 (MgO-Ca(H2PO4)2), and the composite remediation agents of montmorillonite, MgO, and Ca(H2PO4)2 (Imvite-MgO-Ca(H2PO4)2). Bioelectrochemical systems (BES) effectively reduced ARGs abundance, and when combined with Imvite-MgO-Ca(H2PO4)2, lowered the risk of ARGs proliferation linked to antibiotic deactivation. Changes in Pb concentration and pH reshaped microbial communities, impacting both LRGs and ARGs. To reduce the risk of ARGs proliferation and transmission during, various control strategies, such as modifying Pb stress, adjusting pH, and manipulating microbial community structure, have been proposed. The study provided theoretical foundation and practical strategies for controlling ARGs dissemination during the remediation of heavy metal-contaminated soil. [ABSTRACT FROM AUTHOR]

In order to explore the frost heave and thaw settlement characteristics of soil layers in the Sanya Estuary Channel Project, the frost heave rate and thaw settlement coefficient of gravel sand, fine sand, silty clay, and clay are obtained. The most unfavorable soil layers are then compared and analyzed. The variation law of frost heave and thaw settlement performance of the most unfavorable soil layer under different water content is studied. The results are as follows: (1) The freezing stage of the passage through the typical soil layer is divided into four stages: frost shrinkage, rapid frost heave, slow frost heave, and frost heave stability. The melting stage is divided into three stages: slow thaw settlement, rapid thaw settlement, and thaw settlement stability. (2) The most unfavorable soil layer in the typical soil layer of the Sanya Estuary Channel Project is silty clay, with a frost heave rate and thaw settlement coefficient of 4.51% and 5.88% at −28 °C. (3) The frost heave and thaw settlement performance of the most unfavorable soil layer is linearly related to water content. The larger the water content, the greater the frost heave rate and thaw settlement coefficient, and the more prone to damage. [ABSTRACT FROM AUTHOR]

Pollution from organic molecules is a major environmental issue that needs to be addressed because of the negative impacts of both the harmfulness of the molecule structures and the toxicity that can spread through natural media. This is mainly due to their unavoidable partial oxidation under exposure to air and solar radiation into diverse derivatives. Even when insoluble, the latter can be dispersed in aqueous media through solvatation and/or complexation with soluble species. Coagulation–flocculation, biological water treatments or adsorption on solids cannot result in a total elimination of organic pollutants. Chemical degradation by chlorine and/or oxygen-based oxidizing agents is not a viable approach due to incomplete mineralization into carbon dioxide and other oxides. A more judicious strategy resides in mimicking natural oxidation under ambient conditions. Soils and aqueous clay suspensions are known to display adsorptive and catalytic properties, and slow and complete self-regeneration can be achieved in an optimum time frame with a much slower pollution throughput. A deep knowledge of the behavior of aluminosilicates and of oxidizing species in soils and aquatic media allows us to gain an understanding of their roles in natural oxidative processes. Their individual and combined contributions will be discussed in the present critical analysis of the reported literature. [ABSTRACT FROM AUTHOR]

The effect of breakable particle corners is often overlooked in research on pile–soil interaction, which hinders the understanding of the uplift pile behaviors in calcareous sand. This research examines the breakable corner effects on uplift pile–soil interaction in calcareous sand from macro to micro, through model tests and coupled discrete element method–finite difference method. Results revealed that compared to that in silica sand, the higher bearing capacity and relatively abrupt failure behavior of uplift piles in calcareous sands were attributed to the corner interlocking effect and corner breakage effect, respectively. The unstable load transmission along piles in calcareous sand was thoroughly explained by a coupled effect of corner interlocking and breakage. Furthermore, the reduction in effective contacts and alterations in soil skeletons were identified as critical factors contributing to the distinctive soil behaviors in calcareous sand. Moreover, the relative sliding distance of particles was found to be the key factor in determining the amount of corner breakages due to stress concentration at corners. Lastly, a positive feedback loop involving corner breakage effects was proposed, successfully explaining the distinctive phenomenon of uplift piles in calcareous sand. This study provides new perspectives to clarify distinctive pile–soil interaction behaviors in calcareous sand. [ABSTRACT FROM AUTHOR]

This paper presents a consolidation model for stone column-reinforced soft ground subjected to time-dependent loading under free strain condition. Smear effects and three types of loadings, namely, constant loading, ramp loading, and sinusoidal loading, are considered in the developed consolidation model, which is solved by a numerical method based on a partial differential equation solver. The applicability of the proposed consolidation model and the reliability of the numerical method are demonstrated and verified by well-predicting the consolidation behaviors of two practical engineering cases and one laboratory experiment. The verified model and the numerical method are then employed to investigate the effects of smear zone and time-dependent loading on consolidation characteristics of stone column-improved soft ground. The results indicate that the excess pore water pressure undergoes a sharp change at the interface between the smear zone and the undisturbed zone due to smear effects. The smaller the range of the smear zone, the faster the settlement of the composite foundation develops. The faster the loading rate, the faster the dissipation of excess pore water pressure and the faster the settlement develops. In addition, for the foundation subjected to sinusoidal loading, the higher loading frequency results in a larger amplitude corresponding to the excess pore water pressure and a smaller amplitude corresponding to the settlement of the soil. [ABSTRACT FROM AUTHOR]

The design of column-supported embankments requires a comprehensive evaluation of overall stability and failure mechanisms. Previous research has investigated stress characteristics and failure modes of deep mixing (DM) columns under embankment loads. Depending on column configurations, those near the embankment toe experience flexural potential bending or tilting failure, while those closer to the centre are prone to shear failure. As column spacing decreases, a shift from bending to tilting failure occurs. Inadequate column bending capacity increases the risk of tilting-induced embankment collapse. This study initially showcases the efficacy of geosynthetics in mitigating tilting failure in columns with smaller spacings. The interaction between geosynthetics and diverse configurations on the failure mechanisms of DM columns is meticulously examined. A crucial shift in the failure mechanism from tilting to bending is facilitated by the application of conventional geosynthetics with tensile stiffness, particularly in scenarios with restricted spacing. Geosynthetics effectively mitigate lateral soil displacement, enhance column bending capacity, and intricately redistribute lateral pressures exerted on the columns. Ultimate load, shear strain, and stress are analysed both with and without geosynthetics. Lastly, the influence of geosynthetics on soil reaction distribution and internal forces within columns is deliberated. [ABSTRACT FROM AUTHOR]

Mechanical response of soils under simple shear conditions has long been a subject of significant interest in the field of geomechanics. When subjected to simple shear loading, soils experience rotations of the principal stress directions. To provide a unified description for the simple shear behavior of clay and sand, this paper proposes a novel critical state model that accounts for the influence of principal stress rotation (PSR), based on the unified critical state model for overconsolidated clay and sand with subloading surface (CASM-S). The novelty of the newly proposed model, which is named as CASM-SP, lies in its ability to consider the influence of direction of the stress increment when establishing the plastic flow rule that is suitable for both clay and sand. Therefore, the model can capture the mechanical response of soils resulting from the PSR loading mechanism, such as noncoaxial behaviors. Then, the newly proposed model is validated through the comparisons with a series of experimental data of clay and sand under both drained and undrained simple shear conditions. Results predicted by the CASM-SP model agree well with those from the experiments, demonstrating that CASM-SP can reasonably describe the simple shear behavior of both clay and sand. [ABSTRACT FROM AUTHOR]

Clarifying the response relationship between soil radon gas anomalies and active fault tectonic geomorphology, and to explore a rapid prediction method for concealed fractures, soil radon gas measurements and unmanned aerial vehicle micro-geomorphic scanning were carried out in the basin section of the Aba South Fault in western Sichuan. The areas of radon gas anomalies and tectonic features formed by fracture activities are highly consistent with the distribution areas of hidden fractures. It is concluded that the combination of soil radon gas measurements and tectonic geomorphologic analysis can rapidly and accurately predict hidden fractures covered by Quaternary sediments. [ABSTRACT FROM AUTHOR]

Radioactive cesium rich microparticles (CsMPs) could partially increase 137Cs concentration of the samples collected from the environment after the Fukushima Daiichi Nuclear Power Plant accident. In this study, we investigated the vertical distribution of CsMPs in soils collected from Fukushima Prefecture, Japan. The distribution of CsMPs was relatively large in the soil surface layer. However, the proportion of CsMPs in the RCs concentration at each soil depth was not large, less than 10%. [ABSTRACT FROM AUTHOR]

The activity concentrations of 238U, 232Th, and 40K were determined at 56 sites along the East Coast of India, near the Bay of Bengal, with 31 sites in Odisha and 25 in Andhra Pradesh. In Odisha, average concentrations were 109 ± 13 Bq kg−1 for 238U, 296 ± 27 Bq kg−1 for 232Th, and 450 ± 33 Bq kg−1 for 40K, while in Andhra Pradesh, they were 51 ± 13 Bq kg−1, 149 ± 16 Bq kg−1, and 236 ± 21 Bq kg−1, respectively. Absorbed dose rates and annual effective doses were higher outdoors and indoors in Odisha compared to Andhra Pradesh. The calculated radiological parameters exhibited elevated values at certain sampling locations; however, overall, the values generally complied with regulatory standards. [ABSTRACT FROM AUTHOR]

Rammed earth techniques have a long history and are widely used in the Mediterranean and China. These traditional techniques developed independently in the two regions, producing differences and similarities. Tools and materials as two essential aspects are compared in this paper. For ease of movement and secure fixing, formworks comprise forms, end-stops, and retaining devices. The latter determines how the formwork is used. The formwork size represents the main difference and influences various aspects. Although the choice of the earth for construction is similar, the different local soil components and materials constitute essential differences in reinforcing rammed earth in the two areas. [ABSTRACT FROM AUTHOR]

Landslide susceptibility maps can provide important information for managing regional landslide risks. Traditionally, data-driven and physically-based models are widely used for rainfall-induced landslide susceptibility mapping, but each method has limitations. In this study, a hybrid method that integrates a data-driven model and a physically-based model is proposed for rainfall-induced landslide susceptibility mapping, where the uncertainty in the soil properties can be explicitly considered. The proposed method is illustrated with landslide susceptibility mapping in Shengzhou County, Zhejiang Province, China. Logistic regression is used as the data-driven model, and the regional assessment of rainfall-induced landslides model (RARIL) is used as the physically-based model. Three hybrid models are developed. Hybrid model I, which considers soil parameters uncertainty, is compared with hybrid models II and III, which do not consider it. Results indicate that all the three hybrid models outperform the conventional logistic regression and RARIL models. Notably, hybrid model I, which considers the soil parameters uncertainty, outperforms hybrid models II and III, which do not consider it. [ABSTRACT FROM AUTHOR]

To evaluate the seismic performance of a prestressed concrete-steel hybrid (PCSH) wind turbine tower, the seismic fragility curves based on incremental dynamic analysis (IDA) and multiple stripe analysis (MSA) on a two-scale model are presented and compared. The peak ground acceleration (PGA) and peak lateral drift on the top of the tower are adopted as the intensity measure (IM) and engineering demand parameter (EDP) of analysis, respectively. Finally, the seismic performance of the PCSH tower subjected to seismic action at different soil is investigated. The fragility curves obtained by IDA and MSA methods are compared. [ABSTRACT FROM AUTHOR]

The soil moisture (SM) balance is affected by afforestation. In this study, the CiteSpace software was used to review the literature on the impact of afforestation on SM, and we further present research findings on the Loess Plateau (LP) as follows: (1) the spatio-temporal heterogeneity of SM varies depending on the research scale; (2) the presence of a dried soil layer significantly hinders deep SM recharge; (3) the accumulation of net primary productivity (NPP) may be occurring at the expense of SM. The following research topics are discussed: (1) the recharge and consumption of deep SM in LP; (2) the green water footprint and its shortage of non-crop greenery for evaluating SM allocation and use; (3) the development of inclusive models encompassing different spatial scales to assess the limits of soil water carrying capacity for vegetation (SWCCV). [ABSTRACT FROM AUTHOR]

The relationship between humanity and the soil is an increasingly important topic in social theory. However, conceptualisations of the soil developed by anticolonial thinkers at the high point of the movement for self-determination between the 1940s and the 1970s have remained largely ignored. This is a shame, not least because theorists like Eric Williams, Walter Rodney, Suzanne Césaire and Amílcar Cabral were concerned with the soil. Building on recent work on human-soil relations and decolonial ecology, we argue that these four thinkers conceptualised the connection between soil, empire, and anticolonial revolt. Williams and Rodney ground understanding of soil degradation in global relations of economic power, while Césaire and Cabral reconceptualise postcolonial nationhood in terms of the mutability and diversity of the soil. The article concludes by suggesting that these two anticolonial counterpoints, global connectivity and more-than-human identification, anticipate and deepen contemporary attempts to decolonise ecological thinking. [ABSTRACT FROM AUTHOR]

This study establishes a theoretical framework for analyzing the lateral oscillation of marine pipe piles. The additional mass model is introduced herein to consider the inertial fluctuation effect of the soil plug. Analytical mathematical methods are used to determine the complex impedance variation of the pile over a range of frequency effects. An investigation is performed to determine how the presence of soil plugs changes the lateral complex stiffness and natural frequency of pipe piles. Additionally, comparisons of the applicability of the plane strain model and continuous medium model have been conducted to enable the easy use of the theoretical model. The main conclusions can be drawn as (1) if the fluctuation inertia effect of the soil plug is not taken into consideration, the dynamic active length and the dynamic stiffness of the pipe pile will be underestimated; (2) for the soft soil, the plane strain model may give rise to substantial calculation errors attributed to them regardless of the vertical continuity of the soil, nevertheless, the calculation error decreases rapidly with the increase of soil shear modulus and vibration frequency. [ABSTRACT FROM AUTHOR]

This study presents the effects of moisture variation and the influence of matric suction on the permanent deformation (PD) of three tropical soils with different geological-geotechnical characteristics used in road subgrades in southern Brazil. The experimental programme consisted in determining the soil-water characteristic curves and in dynamic triaxial tests to obtain the PD in different compaction and post-compaction moisture contents. The variation of compaction moisture content caused microstructural changes, influencing the plastic behaviour of soils: the higher the initial moisture content, the greater their accumulated permanent deformations. As expected, the post-compaction moisture variation (wetting process) tended to increase the plastic deformation of materials, evidencing the influence of the suction variation on the performance of the soils studied. In addition, matric suction proved to be the best variable to represent the effects of moisture variation on the plastic behaviour of soils subjected to cyclic loading. Thus, a PD prediction model for tropical soils with the inclusion of this parameter was proposed. The model proved to be highly predictive and may become an important tool to be incorporated into current mechanistic-empirical design methods. [ABSTRACT FROM AUTHOR]

The impact of non-linear soil behaviour on seismic hazard in low-to-moderate seismicity areas is often neglected; however, it may become relevant for long return periods. In this study, we used fully non-linear 1-D simulations to estimate the site-specific non-linear soil response in the low seismicity area, using the city of Lucerne in Switzerland as an example. The constitutive model considers the development of pore pressure excess and requires calibration of complex soil models, including the soil dilatancy parameters. In the absence of laboratory measurements, we mainly used the cone penetration test data to estimate the model variables and perform inversion for the dilatancy parameters. Our findings, using Swiss building code-compatible input ground motions, suggest a high probability of strong non-linear behaviour and the possibility of liquefaction at high ground motion levels in the case study area. While the non-linearity observations from strong-motion recordings are not available in Lucerne, the comparison with empirical data from other sites and other methods shows similarity with our predictions. Moreover, we show that the site response modelled is largely influenced by the strong pore pressure effects produced in thin sandy water-saturated layers. In addition, we demonstrate that the variability of the results due to the input motion and the soil parameters is significant, but within reasonable bounds. [ABSTRACT FROM AUTHOR]

The analytical solution of the steady-state seepage field of a circular cofferdam in nonhomogeneous layered soil of finite depth is derived, including the head function, exit hydraulic gradient formula, and seepage flow formula. The head function is obtained by dividing the circular cofferdam seepage field into regions and then using the separated variable method combined with the Sturm–Liouville theory, and the unknown coefficients in the head function are determined by constructing a system of equations through the integral transformation of the Bessel function. Based on the head function, an analytical equation is also given for the exit hydraulic gradient and seepage flow. The accuracy of the proposed analytical solution is verified by a comparison with numerical results as well as with the results of other methods. The proposed analytical solution is a display analytical solution without singularities and can be used as an effective tool for the analysis of circular cofferdam seepage problems. [ABSTRACT FROM AUTHOR]

The large particle sizes of railway ballast and rock fill have meant that conventional techniques used to measure the small-strain stiffness of finer geomaterials have not been adopted, with the consequence that their stiffnesses are poorly defined. In a series of tests on a UK railway ballast, simple adaptations were made to existing local strain measuring systems to account for the larger particle sizes. The study showed that the small-strain stiffnesses are different in second loading compared to virgin loading, but multiple cycles had little further effect on the stiffness. The large particle size was found rarely to have any detrimental effect on the quality of the strain measurements and the two independent measurements of axial strain taken at diametrically opposite locations were generally as consistent as for finer grained soils. As for other soils, the 'external' measurements of strain across the apparatus platens were of little use in determining stiffness. The presence of water did not have a significant effect on the behaviour, and this was confirmed by inter-particle loading tests on single particle contacts. Despite the use of lubricated end platens, there was a significant barrelling of the sample at large shear strains so that the internal measurement of the volumetric change diverged from the external measurement at large strains. The very small volumetric strains that occurred during isotropic loading meant that each sample could only be used to obtain one measurement of the virgin loading stiffness. [ABSTRACT FROM AUTHOR]

This paper forms part of the SINEW (sinkhole early warning) project and continues the work conducted by Möller and co-workers in 2022, where 1g experiments demonstrated the feasibility of using distributed fibre-optic sensing (DFOS) for sinkhole early warning. Their experimental campaign highlighted an order of magnitude difference in the strain between the soil and the cable that remains unexplained and weakens confidence in the technology and/or the experimental method. This paper uses three-dimensional finite-element analyses to examine further this discrepancy and the soil–cable interface. The results support the experimental findings and demonstrate that the DFOS signature strain profile is induced by the horizontal movement of the ground, and enhanced when sufficient coupling at the soil–cable interface is achieved. This result holds when modelling is scaled to realistic confining pressure, and its significance is twofold. First, this needs to be accounted for in the DFOS laying technique. Second, particles of cohesionless soils undergo relatively high horizontal displacement away from the centre of the sinkhole, and this means that DFOS cables are able to detect subsidence away from the centre of the sinkhole. The paper illustrates this result and the signature strain profile expected in this case. [ABSTRACT FROM AUTHOR]

Quantifying the process of particle breakage is essential whenever a macroscopic investigation into the phenomenon is addressed. Some authors relate an indicator of the evolution of particle breakage, usually the surface created, to a measure of the mechanical loading. Others refer to the evolution of the particle size distribution (PSD) to better understand the problem. In this study, a shape factor of the PSD curve is used as a breakage parameter. The slope of the linear trendline of the PSD in a log-log plot was found to be reasonably representative of the shape of the PSD, for engineering granular materials. It was shown that the new breakage parameter is adapted to both well graded and uniformly graded materials, but cannot be used to describe gap-graded soils. This parameter is first studied from a micromechanical point of view, before being compared to three widely used breakage parameters: Hardin, Marsal and Einav's breakage parameters. The transition between these three parameters and the proposed parameter is provided. The main objective of this study is to allow the operation and utilisation of experimental results, which are reported in the literature through one of the available breakage parameters, or through PSD plots. [ABSTRACT FROM AUTHOR]

Since Artificial ground Freezing (AGF) appeared in the 1880s in the mining sector in Europe, it has been used for various construction applications worldwide. In recent years, it has been increasingly popular in urban projects due to its versatility and applicability to complicated site conditions. So far, it has been used to stabilize substrata to nearly 1,000 m below the ground surface, which is considered not possible for many other ground improvement technologies. Due to the growth in field applications, the practice and theories related to AGF have become more mature in the most recent two decades. The improvement in understanding of this topic is a result of lessons that have been learned through numerous projects, as well as a variety of comprehensive studies that have been completed. This paper reviews the existing practice, the recent development on AGF and the challenges of AGF. [ABSTRACT FROM AUTHOR]

Research on the SSI effect on flat sites has yielded many valuable conclusions. However, current research on the impacts of various special local terrains on structural dynamics remains limited. For mountainous areas, it is common to construct houses in a multi-step, climbing, and laterally staggered architectural form that follows the mountain terrain. Only through the analysis of the combined action of the upper and lower parts can the seismic performance of this type of structural form be better revealed; considering the influence of SSI effects will be closer to the actual seismic effects. Therefore, to identify the damage factors of the mid-story isolated stilted structures under earthquakes and provide optimized design plans for the structures, six models are established considering three slopes and two types of foundations based on the engineering case in Chongqing, China. Through the elastic-plastic time-history analysis under earthquakes in the down and transverse-slope directions, concludes, compared with not considering SSI, the seismic response of the mid-story isolated stilted structures considering SSI in mountainous areas is amplified. With the increase of the mountain slope, the seismic response of the structures considering SSI increases, and the amplification coefficients are between 1–1.8. The amplification coefficients of the structures without SSI are concentrated around 1, which is less influenced by the slope. The damage to the stilted isolated layer is mainly concentrated in the column and the beam end, and the maximum seismic response appears in the short columns. The foundation soil stress increases with the increase of the mountain slope. [ABSTRACT FROM AUTHOR]

Background: Tetanus is a clinical rarity due to the successful globally adopted childhood vaccination programme. The rising elderly population in the United Kingdom creates a subset of individuals whom are prone to develop Tetanus as they preceded this vaccination drive. Case summary: A 76 year old Caucasian lady presented with a soil contaminated laceration injury on her knee following a fall. Though she received urgent assessment and wound care, the relevance of the injury in the backdrop of her age was not appreciated and her tetanus post exposure prophylaxis was overlooked. She readmitted seeking further management 1 week later with an infected wound with Trismus and clinical features favoring Generalized tetanus. During her stay she developed Takotsubo-cardiomyopathy with congestive cardiac failure and required prolonged care in the intensive unit with mechanical ventilation and rehabilitation before being discharged home. Conclusion: First contact physicians should have a greater appreciation of the types of injuries and at-risk individuals who are more prone to develop tetanus upon exposure to ensure early and appropriate identification. There should be greater situational awareness with regard to the elderly in view of their heightened risk of development of tetanus specially those born before the vaccination drive. Knowledge regarding post exposure prophylaxis measures for tetanus should be regularly updated using local guidance to ensure awareness, so as to despite its rarity Tetanus remains an adequately appreciated disease. [ABSTRACT FROM AUTHOR]

Background: Tetanus is a clinical rarity due to the successful globally adopted childhood vaccination programme. The rising elderly population in the United Kingdom creates a subset of individuals whom are prone to develop Tetanus as they preceded this vaccination drive. Case summary: A 76 year old Caucasian lady presented with a soil contaminated laceration injury on her knee following a fall. Though she received urgent assessment and wound care, the relevance of the injury in the backdrop of her age was not appreciated and her tetanus post exposure prophylaxis was overlooked. She readmitted seeking further management 1 week later with an infected wound with Trismus and clinical features favoring Generalized tetanus. During her stay she developed Takotsubo-cardiomyopathy with congestive cardiac failure and required prolonged care in the intensive unit with mechanical ventilation and rehabilitation before being discharged home. Conclusion: First contact physicians should have a greater appreciation of the types of injuries and at-risk individuals who are more prone to develop tetanus upon exposure to ensure early and appropriate identification. There should be greater situational awareness with regard to the elderly in view of their heightened risk of development of tetanus specially those born before the vaccination drive. Knowledge regarding post exposure prophylaxis measures for tetanus should be regularly updated using local guidance to ensure awareness, so as to despite its rarity Tetanus remains an adequately appreciated disease. [ABSTRACT FROM AUTHOR]

This paper presents a new type of large-diameter multi-disc soil anchor and its cavity-forming tool. The large-diameter multi-disc soil anchor is obtained by adopting a toothed chain, centrifuging holes to form cavities, forming multiple cavities, placing a steel strand with centering support, injecting cement mortar, and curing. In order to study the uplift bearing characteristics and creep property of the large-diameter multi-plate soil anchor, the equal-diameter soil anchor was taken as the control group. The ultimate pull-out bearing capacity, vertical displacement, axial force, anchor plate bearing load, and side friction resistance were simulated and analyzed by FLAC3D 5.0 64-bit software, and the creep property test of the anchor bolt was carried out. The results show that under the same conditions, the ultimate pulling capacity of the large-diameter multi-disc soil anchor is 125% higher than that of the same-diameter soil anchor. The vertical displacement of the large-diameter multi-disc soil anchor decreases by 51.74% compared with that of the equal-diameter soil anchor when the ultimate uplift capacity is reached. The side friction resistance of the large-diameter multi-disc soil anchor is small and its growth rate is slow. When the ultimate pulling capacity is reached, the load sharing of the anchor disc accounts for 76.54% of the total load applied. The creep rate of the large-diameter multi-plate soil anchor bolt is 0.91 mm, and the creep rate of the equal-diameter soil anchor bolt is 1.69 mm. By fitting the data, it is found that the large-diameter multi-disc soil anchor provides a method to increase the anchorage force of the soil anchor, and the research on its bearing characteristics and creep property provides a theoretical basis for the application of the soil anchor. [ABSTRACT FROM AUTHOR]

In the field of tunnels, the stability of tunnel faces is generally considered in dry, saturated and homogeneous soils. However, the actual condition of some soils has been found to be inhomogeneous, with unsaturated seepage. In this paper, an analytical method is applied to estimate the safety factor when the supporting force at the tunnel face is zero under steady unsaturated seepage and inhomogeneous conditions. This method combines kinematic limit analysis techniques with strength reduction techniques; an efficient stress formulation utilizing suction stress is employed to determine the apparent cohesive force to obtain the solution of the steady unsaturated seepage problem, and indicators of soil inhomogeneity are attributed to the effect on cohesion. A 3D log-spiral collapse mechanism is used to find the zero supporting pressure and determine the safety factor through an iterative method. This paper analyzes the effect of variations in the unsaturated parameters, inhomogeneity parameters and tunnel dimensional parameters on the stability of the tunnel face. [ABSTRACT FROM AUTHOR]

Due to its simple design and cost-effectiveness, Bromhead ring shear apparatus is widely used to assess the drained residual strength through various testing procedures such as single stage, preshearing, and multistage. However, when compared to back-calculated case histories, values obtained through these testing procedures were found to be higher due to wall friction. To address this, Stark and Vettel (Geotech Test J 15:24–32, 1992) have introduced the "Flush testing procedure" which involves adding remolded soil to the specimen and reconsolidate it, in order to minimize the wall friction. Although the procedure yielded satisfactory results, it is more time-consuming. This paper presents a comparison between a proposed preconsolidated presheared flush (P.P.F) and flush testing procedures. The test results showed that this procedure has successfully minimized the effect of wall friction, providing values lower than those obtained using the flush procedure in shorter time. [ABSTRACT FROM AUTHOR]

Rayleigh wave isolation using metamaterials is a research hotspot in the engineering community, yet the development of relevant mitigation methods remains an open and challenging problem. Herein, we propose a new type of metasurface, known as an engineered metagrating, which is a special metasurface buried in soil and plays a role in shielding surface Rayleigh waves. Moreover, the total omnidirectional reflection characteristics and subwavelength properties exhibited by the proposed metasurface provide a more flexible reference for surface Rayleigh wave mitigation measures in practical engineering applications. This work can open new avenues for controlling the propagation of seismic surface waves. [ABSTRACT FROM AUTHOR]

This paper records six species and five genera of mites in the family Laelapidae from soil in Punjab, Pakistan. Five species are recorded from Pakistan for the first time – Euandrolaelaps karawaiewi (Berlese, 1904), Gaeolaelaps minor (Costa, 1968), Gymnolaelaps kabitae Bhattacharyya, 1968, Ololaelaps translineatus (Barilo, 1991), and Stratiolaelaps scimitus (Womersley, 1956). Cosmolaelaps lutosus sp. nov. is described as a new species. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The design of large-scale pile foundation systems is routinely assisted by finite element simulations. To a large extent, both the modeling and the computational effort of such analyses are governed by the adopted pile modeling technique. The traditional approach to this problem fully resolves the pile and soil domain employing solid elements, resulting in considerable meshing constraints and high simulation runtimes that may be regarded as unbearable for many practical purposes. As an attractive alternative to circumvent these obstacles, embedded FE models have become increasingly popular in solving this modeling task, mainly due to their flexible meshing procedure and significantly enhanced runtime efficiency. In a preceding contribution, the authors have proposed an extended formulation that provides a rigorous framework to capture soilstructure interaction effects at the physical soil-pile contacts. As a key feature, the implemented combined soil-pile coupling scheme explicitly accounts for endpoint interaction. However, validation studies have been constrained to single pile analyses to date. The present work expands this validation scope to largescale boundary value problems involving multiple piles and investigates the model performance based on three different case studies. The results are compared to both, measurements and numerical benchmark solutions and provide exclusive insight into the numerical fidelity of the developed embedded FE model, with a view to increasing its potential for take-up in engineering practice. [ABSTRACT FROM AUTHOR]

The main chemical, ecotoxicological, and environmental fate characteristics of cyanide, along with its treatment methods for cyanide-contaminated wastewater, were thoroughly examined. A global biogeochemical cycle of cyanide is proposed, covering the key physicochemical processes occurring in aqueous, soil, and atmospheric environments. The principles, advantages, and disadvantages of various treatment methods—including chemical, physicochemical, electrochemical, photochemical, and biological approaches—are evaluated. Finally, the feasibility of reusing cyanide waste is explored. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bond–slip behavior of concrete pile–cemented soil interface is crucial for load transfer analysis of stiffened deep cement mixing piles, which is greatly influenced by ground temperature and age during long-term curing. However, the thermal–temporal effect on the frictional characteristics of this interface remains unclear. In this paper, an element-scale specimen of concrete pile–cemented soil interface was first designed. Then interfacial shear tests were performed on batches of samples subjected to varied curing temperatures (T) and ages (t) to obtain interfacial bond–slip (τ‒s) curves. The test results showed that the interfacial peak shear strength (τu) increased with the growth of T and t. Based on the experimental observations, a strength development model for τu considering the thermal effect was established. Subsequently, a disturbed state concept (DSC)-based constitutive model incorporating the thermal–temporal effect was proposed for the investigated interface. Both prepeak and postpeak stages of the τ‒s curves can be effectively described by the developed DSC model, exhibiting robust performance in fitting and predicting experimental results. Finally, the DSC model was cross-validated by the interfacial τ‒s data sets collected from reported experimental publications. Across all data sets, the coefficient of determination (R2) exceeded 0.9, and the mean absolute percentage error of τu remained below 10% when comparing predictions with measurements, which strongly highlights the generalization capability of the DSC model. [ABSTRACT FROM AUTHOR]

Introduction: Intercropping and soil properties both affect soil diazotrophic communities. However, the specific effects that alfalfa-maize intercropping has on diazotrophic networks and community diversity under different soil properties remain unclear. Methods: In this study, we investigated the soil diazotrophic communities of two crop systems, alfalfa monoculture (AA) and alfalfa-maize intercropping (A/M), in two sites with similar climates but different soil properties (poor vs. average). Results and discussion: The diazotrophic network complexity and community diversity were higher at the site with poor soil than at the site with average soil (p < 0.05). Community structure also varied significantly between the sites with poor and average soil (p < 0.05). This divergence was mainly due to the differences in soil nitrogen, phosphorus, and organic carbon contents between the two sites. At the site with poor soil, the A/M system had lower diazotrophic diversity, lower network complexity and greater competition between diazotrophs than the AA system (p < 0.05) because intercropping intensified the soil phosphorus limitation under poor soil conditions. However, in the average soil, it was the A/Msystemthat had an altered diazotrophic structure, with an increased abundance of 11 bacterial genera and a decreased abundance of three bacterial genera (p < 0.05). Conclusion: Our results indicated that the effects of alfalfa-maize intercropping on diazotrophic communities were soil property-dependent. [ABSTRACT FROM AUTHOR]

The stubby root nematode, Paratrichodorus allius, is one of the most important plant-parasitic nematodes. Besides root feeding, P. allius also transmits the Tobacco rattle virus in potatoes, which causes corky ringspot disease. Rapid detection of P. allius is key for efficient management. This study was conducted to develop a real-time recombinase polymerase amplification (RPA) assay that is capable of detecting P. allius directly in DNA extracts from soil using a simple portable device in real time. A fluorophore-attached probe was designed to target the internal transcribed spacer (ITS)-rDNA of P. allius and was used along with primers designed previously. The real-time RPA assay had the ability to detect P. allius DNA extracted directly from infested soil with a sensitivity of one-sixteenth portion of a single nematode. This RPA assay was specific, as it did not produce positive signals from non-target nematodes tested. The real-time RPA was found to be rapid as it could even detect P. allius in as little as 7 min. Testing with 15 field soil samples validated the RPA assay developed in this study. This is the first report of P. allius detection directly from soil DNA using real-time RPA and is the fastest method for P. allius detection in soil to date. [ABSTRACT FROM AUTHOR]

The tapered pile is usually divided into finite segments along the vertical direction due to its variable cross-section when investigating its torsional dynamic characteristics. However, an annular projection would be formed at the contact surface of the adjacent pile segments due to the difference in radius, through which the surrounding soil will apply the circumferential support on the pile segment. In this study, the Voigt model is adopted to model the circumferential support of the surrounding soil acting on the annular projection. On this basis, an amended impedance function transfer method is established combined with the circumferential stress equilibrium equations and circumferential displacement continuity conditions at the contact surface of the adjacent pile segments. The shear complex stiffness transfer method is employed to consider the construction disturbance during pile installation. Then, an improved analytical solution for the torsional vibration of the tapered pile considering the circumferential support of the surrounding soil is established by solving the equations for the soil and pile. Based on the solution, the torsional vibration of the tapered pile is investigated and the influence of the circumferential support of the surrounding soil is revealed under different pile parameters and construction disturbance conditions. [ABSTRACT FROM AUTHOR]

Consolidation is the combined phenomenon of the compression and groundwater seepage of clay. Accurate evaluation of the consolidation characteristic is essential for the design, construction, and long-term stability of geotechnical structures. In this study, a strain-controlled non-linear finite strain model for constant rate-of-deformation (CRD) consolidation was developed for quickly and reliably predicting the consolidation behavior of clay soils. The model can account for any form of non-linear compression and permeability relationships, thus considering variations in the coefficient of consolidation. Being strain-controlled, it overcomes the limitations of stress-controlled models which require complex numerical iteration. The validity and accuracy of this model were verified through rigorous comparisons with both numerical simulations and experimental data. For normally consolidated soils, a non-linear e-lgσ′compression model was used instead of a linear compression model. For overconsolidated soils, the Harris function compression model was determined to be recommended to overcome the discontinuities in total stress and pore pressure caused by the traditional piecewise e-lgσ′ model. It was also found that determining the steady state of consolidation for normally consolidated soils should use the non-linear method, while the linear method is suggested to be adopted for overconsolidated soils. [ABSTRACT FROM AUTHOR]

Copyright of Research of Soil & Water Conservation is the property of Institute of Soil & Water Conservation, Chinese Academy of Sciences & Ministry of Water Resources and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although almost a third of the world's population is exposed to iodine deficiency (ID), and supplementation programs such as enriching table salt have been carried out or are being carried out at the global and national level, in many regions of the world, people are facing an increase in iodine intake, which is mainly due to the presence of large amounts of iodine in water, soil, agricultural products, or high consumption of seafood. Published articles were indexed in the Scopus database (from 2000 to 1 April 2023) were reviewed and analyzed by VOSviewer software. The results showed the growing interest of researchers over the last 20 years in environmental iodine intake. The results of this study can have a significant impact on the planning and policy-making of relevant officials and communities to supply the needed iodine. [ABSTRACT FROM AUTHOR]