Soil Parameters Research Articles

Research on diffusion mechanism of grouting slurry in slope gravel soil

Grouting reinforcement method is one of the effective methods commonly used in slope reinforcement. At present, grouting reinforcement technology is mostly aimed at sandy soil and clay, and the research on gravel soil is still relatively few. At the same time, because of the strong concealment of slurry diffusion in grouting reinforcement, the process and law of slurry diffusion in grouting process has always been a difficult problem. In this paper, through numerical simulation analysis and indoor simulation grouting test, the law of slurry diffusion flow in slope gravel soil grouting is analyzed, and compared with the law of slurry diffusion in sand. At the same time, the pressure distribution along the slurry diffusion process and the changes of soil parameters before and after grouting are also analyzed. The results show that the final diffusion radius of slurry is proportional to the water-cement ratio and grouting pressure of cement slurry, and the diffusion radius of slurry in slope gravel soil is much larger than that in sand. In slurry diffusion, the pressure along the road gradually attenuates with slurry diffusion, and its attenuation rate is inversely proportional to the water-cement ratio of cement slurry. The attenuation rate in slope gravel soil layer is much slower than that in sand layer. After the slope gravel soil layer and sand soil layer are strengthened by grouting, the porosity of the soil layer decreases and the compressive strength increases. The research results indicate the diffusion law of grouting slurry in slope gravel soil and provide reference for similar engineering designs.

Enhancing soil quality in intensive rice cultivation through short-term growth of green manure and its incorporation combined with rice husk or its ash: a laboratory incubation study

ABSTRACT A novel approach, i.e. mung bean was grown in paddy soil for 1 month as a pre-rice crop, which is a short but a feasible period applicable to the current intensive rice monoculture cropping system in the Vietnamese Mekong Delta. This study aimed to assess how short-term growth of green manure and its incorporation combined with rice husk or its ash impact the soil quality of sandy loam soil and silty clay soil. Four treatments, viz. soil without mung bean (control), soil plus mung bean incorporation, soil plus mung bean and rice husk of 10 Mg ha−1, and soil plus mung bean and rice husk ash of 5 Mg ha−1, were established. Different soil parameters were determined to evaluate their initial effects after incubating for 60 days. In both soils, the incorporation of mung bean significantly increased β-glucosidase, acid phosphatase, and urease activities, as well as C mineralization compared with control. Soil labile C was increased by 15–50% by incorporation of mung bean, irrespective of the application of rice husk or its ash, compared to that in control. The highest total C and available N were found in mung bean combined with rice husk followed by mung bean with rice husk ash, only mung bean, and control. Sandy loam soil with a lower exchangeable K level showed significant improvements in the exchangeable K content with rice husk and its ash amendments. Therefore, these practices, short-term green manure planting, could offer benefits to farmers for enhancing soil quality such as enzyme activities in the intensive paddy cultivation.

Evaluation of Soil Quality in Different Bletilla striata Agroforestry Systems in Eastern China

Agroforestry is being promoted as a feasible land use management to improve understory economic benefits. However, there are few studies on species selection and the comprehensive evaluation of soil quality change in rhizoma bletillae (Bletilla striata) agroforestry systems. The soil quality index (SQI) and minimum dataset (MDS) methods can reflect the overall condition and were effective tools for understanding different cultivation systems. In this study, we evaluated the soil quality of four cultivation models (including three agroforestry systems: PeB, moso bamboo (Phyllostachys edulis)–rhizoma bletillae; PoB, plane trees (Platanus orientali)–rhizoma bletillae; CcB, pecan trees (Carya cathayensis)–rhizoma bletillae; and CK, rhizoma bletillae monoculture. The total dataset (TDS) consisted of 15 soil parameters containing physical, chemical, and biological characteristics. The results showed that soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) were finally selected and established as the MDS. Agroforestry could significantly influence soil quality. Compared with CK, the SQI in CcB significantly increased and decreased in PeB and PoB. Soil water content (SWC), nitrate nitrogen (NO3−-N), dissolved organic carbon (DOC), SOC, TN, and TP contents were higher in CcB than in the other cultivation models. Based on various soil indicators and SQI analysis, the CcB was the best in improving soil quality. These findings showed that the soil quality index based on the MDS can be used as an effective indicator for agroforestry systems selection. It provides theoretical guidance for the practice of bionic cultivation and the sustainable management of rhizoma bletillae.

Estimation of dynamic soil properties for geotechnical analysis in the Niger Delta using index testing and empirical correlations

This study investigated geotechnical properties of subsurface soils from Mbiama town in Rivers State, Niger Delta region through laboratory index testing and development of empirical correlations to estimate dynamic soil parameters. Grain size analyses revealed heterogeneous stratigraphy transitioning from upper clayey sands to lower gravelly sands deposited under changing fluvio-deltaic conditions. Atterberg limits exhibited decreasing plasticity trends with depth confirming the textural variations. Laboratory data conforms to layering architecture inferred from depositional facies analyses. Predictive models were developed relating Standard Penetration Test blow counts (SPT-N) and shear wave velocity (Vs) to depth, moisture content and percentage sand. High regression coefficients validated models' accuracy in reproducing over 90% of field measurements. Factor of safety against liquefaction was correlated to SPT-N, accounting for density-dependent properties. Index-based characterizations aligned well with trends predicted by the empirical correlations. This research demonstrated robust indirect estimation of dynamic geotechnical indices for foundation design and seismic risk analysis in data-scarce Niger Delta through standardized field and laboratory index testing integrated with depositionally-linked predictive models.

Soil Parameters at Critical State for Ho Chi Minh Clay

Soil Parameters at Critical State for Ho Chi Minh Clay

Physical, chemical, and microbiological parameters of soil under different tillage types.

Objective: To determine the effect on the chemical, physical and biological properties of soils under minimum tillage and conservation tillage in different locations in Sinaloa. Design/methodology/approach: The treatments were evaluated using a completely randomized experimental design, with a total of eight treatments or sampling sites, where five samples per site were collected at a depth of 30 cm. A total of 40 samples were obtained, which were preserved in a thermal box and were transferred to the microbiology laboratory of the Faculty of Agronomy (UAS). The variables evaluated included the quantification of bacteria on plates, where the number of total bacterial colonies (TB), phosphate solubilizing bacteria (PSB), nitrogen-fixing bacteria (NF) and indole-promoting bacteria (IPB) were determined. In addition, organic matter, electrical conductivity and pH were determined. Results: Soils under minimum tillage modality significantly promoted higher percentage of organic matter, a greater number of bacterial colonies and higher electrical conductivity compared to soils with conventional tillage modality. Limitations on study/implications: Findings/conclusions: Agricultural tillage intervenes in the physical, chemical and microbiological properties of soils, as the sampling sites where minimum tillage is practiced show a higher concentration of organic matter and therefore leads to greater microbiology and electrical conductivity in those evaluated soils.

Sodium aluminosilicate synthesised from rice straw as a sorption barrier to protect soil from antimony contamination

ABSTRACT A novel effective sorbent for the extraction of antimony(III) from rice straw has been generated, having a specific surface area of 470 m²/g. The material was subjected to a series of analyses, including scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction analysis, and FT-IR spectroscopy. The sorption properties relative to Sb(III) ions were characterised in dynamic conditions in a column experiment. The total dynamic exchange sorption capacity of 113.92 mg/g renders this material suitable for use as a permeable reactive barrier (sorption barrier) with the objective of protecting soils from antimony contamination. To identify the optimal conditions for soil protection, the chemical composition, acid-base properties, and sorption parameters of soils of varying types were characterised. The sorption properties of the soils were determined in static conditions to obtain the sorption isotherm. The maximal sorption capacity was identified for the soil sample with low base saturation and a high organic component content, a finding that was corroborated by DTA analysis. The results of the column experiment with layers of soil and aluminosilicate sorbent indicate the promising use of the new sorbent as a sorption barrier for the effective protection of soils from antimony contamination.

Investigation into the geological radiation levels and evaluation of hazard parameters in soil and rock specimens taken from mining sites across North-Eastern Nigeria

This research quantitatively evaluates the natural radioactivity levels and geological radiation hazard parameters of soil and rock specimens obtained from mining locations in North-Eastern Nigeria, by means of grammar-ray spectroscopy. There have been potential public health risks associated with the use of soil and rock from mining locations in North-Eastern Nigeria, specifically the study areas. A total of twenty-eight samples were systematically gathered from Nahuta and Kashere locations. Through gamma spectrometry employing a NaI (TI) detector, the natural radioactivity levels of 238U, 232Th and 40 K were determined for each and every sample. The findings indicated that the mean activity concentrations of 226Ra, 232Th, and 40 K in Nahuta are 46.13 ± 4.78 Bq/Kg, 34.10 ± 3.02 Bq/Kg and 473.94 ± 5.41 Bq/Kg for the soil samples respectively, and 32.91 ± 0.49 Bq/Kg, 40.70 ± 0.41 Bq/Kg, and 578.18 ± 4.28 Bq/Kg for the rock samples respectively. The corresponding mean activity concentrations of 226Ra, 232Th, and 40 K in kashere are 17.99 ± 4.18 Bq/Kg, 23.73 ± 1.78 Bq/Kg, and 191.65 ± 3.15 Bq/Kg, for the soil samples, and 20.24 ± 3.72 Bq/Kg, 29.09 ± 1.78 Bq/Kg, and 148.36 ± 3.15 Bq/Kg, for the rock samples respectively. An analysis of radiation risk parameters (D, AEDE, Raeq, Hex, Hin, AGDE and ELCR) has been conducted and findings explored. While the samples from the kashere region fall within the international recommended levels, elevated readings of certain radiation health parameters are observed in the Nahuta region, posing serious public health risk due to utilization of the soil and rock from this area in construction activities.

Ground response during of EPB shield shutdown in gravel ground based on coupled CEL-FEM analysis

Ground response during of EPB shield shutdown in gravel ground based on coupled CEL-FEM analysis

Analysis of physico –chemical Parameters of soils collected from Brahmaputra river of Dhubri district, Assam, India

Analysis of physico –chemical Parameters of soils collected from Brahmaputra river of Dhubri district, Assam, India

EFFECTS OF POULTRY LITTER ON SOIL PHYSICO-CHEMICAL PROPERTIES FOR CROP PRODUCTION IN KAURU LOCAL GOVERNMENT AREA, KADUNA STATE, NIGERIA

Poultry litter is an important source of soil nutrients that supports beneficial soil bacteria by serving as a substrate, however, its excessive have adverse effects that lead to soil pollution, contamination and acidification of soil and groundwater. This study analyzed the effects of poultry litter on soil physico-chemical properties for crop production in Kauru Local Government Area, Kaduna State, Nigeria. Data on soil properties at the control and poultry littered sites were collected by sampling four farmlands in Barwa, Ungwan Noma, Kurmin-Shado and Dan-Daura and analyzed in the laboratory. Results were subjected to ANOVA and Correlation analyses tools. The findings revealed significant changes in soil physico-chemical properties due to excessive poultry litter application. Compared to the control site, treated soil showed increased pH (6.26 to 6.89), decreased organic carbon (4.29 to 3.63), increased organic matter (5.92 to 6.99), increased total nitrogen (0.49 to 0.58), altered particle size distribution (clay, silt, sand), reduced aggregate, stability (0.818 to 0.715) and increased CO2 (64.8 to 65.88%). Also, Correlation analysis revealed a significant relationship between poultry litter application and soil physico-chemical properties (Sig. value >0.05), indicating that poultry manure significantly alters soil parameters. The study concludes that while some of the soil properties identified were within safe limits, application of poultry manure altered other properties of the soil. Thus, the study recommends that farmers should use poultry litter in conjunction with other fertilizers and soil amendments to balance nutrient inputs.

Numerical simulation of the lateral load test on piles through a parametric analysis

Pile foundations are utilized to transfer load from the superstructure to the soil mass when the surface layer of the ground exhibits low load-bearing capacity. For an axially loaded pile, the load is transmitted to the soil through lateral friction at the soil-pile interface and via tip resistance. However, these elements are subject to significant lateral forces in addition to vertical ones. The resistance of piles to lateral loads depends on boundary conditions, stiffness, and concrete strength of the pile, as well as soil type, soil stiffness, and soil strength. Several models are employed to analyse laterally loaded piles, including soil modelling using nonlinear springs, commonly known as p-y curves. This article aims to investigate the impact of pile geometric properties, soil type, and the chosen model on simulating soil-pile interaction on the structural performance of a pile embedded in soil subjected to a transverse load. The study encompasses the variation of three pile diameters (60 cm, 80 cm, and 100 cm), three pile lengths (5.5 m, 10.5 m, and 15.5 m), and three soil types (soft clay, stiff clay, and moderately compacted sand). The effects of diameter (D), pile length (L), slenderness ratio (L/D), and soil type on the lateral response of the pile are examined. Additionally, an analysis is conducted regarding the influence of linear and nonlinear (p-y curves) Winkler models on simulating soil-pile interaction. The presented results indicate that the foundation behaviour, when considering soil-pile interaction, is contingent upon various factors and should be rigorously assessed by designers. It is noteworthy that, depending on the soil type, soil modelling using horizontal linear springs yields acceptable results, obviating the need for a nonlinear model. However, when soil particles exhibit friction or low cohesion, a careful analysis of soil parameters and the chosen model for simulating soil-pile interaction is warranted, with numerical simulation via FEM in conjunction with lateral load testing recommended to determine the optimal method.

Archetypal crop trait dynamics for enhanced retrieval of biophysical parameters from Sentinel-2 MSI

Archetypal crop trait dynamics for enhanced retrieval of biophysical parameters from Sentinel-2 MSI

Physicochemical properties of acid sulphate soil profoundly influence the composition of rhizobacterial community of rice (Oryza sativa L.)

Physicochemical properties of acid sulphate soil profoundly influence the composition of rhizobacterial community of rice (Oryza sativa L.)

Physico-chemical Assessment of Soil Quality of Selected Mango Orchards of Dehradun District (Uttarakhand), India

The present study is an attempt to analyze soil nutrition for farming suitability in the orchards of Dehradun. In this study, the physico-chemical analysis was carried out by analyzing important parameters namely pH, electrical conductivity (EC), available nitrogen, available phosphorous, available potassium, organic carbon (OC), and organic matter (OM). Soil samples were collected during the winter season (January-February) and summer (May-June) from selected orchards of Dehradun and compared with the standard value. The range of soil parameters recorded during winter season (pH: 6.2-7.76, EC: 0.08-0.68 ds/m, N: 178.75-413.95 kg/ha, P: 53.86-84.63 kg/ha, K: 98.74-157.5 kg/ha, OC: 1.23-3.78%, OM: 2.12-6.51%) and summer season (pH: 6.1-7.84, EC: 0.10-0.19 ds/m, N: 175.5-282.54 kg/ha, P: 46-65 kg/ha, K: 103.25-189.0 kg/ha, OC: 1.10-2.92%, OM: 1.89-4.96%) were observed. The parameters met soil quality standards except available P, OC, and OM. Available P, OC, and OM recorded higher than permissible limits. Reduction in selected soil parameters except available phosphorus was observed in the summer season, emphasizing the need for effective nutrition management to sustain soil quality. . KEYWORDS :Available nitrogen, Available phosphorous, Available potassium, Electrical conductivity, Organic carbon, Organic matter, pH

On the Significance of Parameter Uncertainties for Prediction of Leak Noise Wave Speed in Buried Pipes

Abstract The modern world is facing the challenging issue of water wastage due to leaks, which is causing severe economic, environmental and social impacts. Consequently, the inspection and maintenance of buried water pipes is crucial and there is still a lack of investigations towards the uncertain parameters affecting the wave speed associated with the predominantly fluid-borne wave s=1, the main carrier of leak noise. This study investigates the effects of uncertainties present in the pipe and soil parameters which are affecting the speed of propagation of the leak noise wave. To achieve this, a sensitivity analysis is performed using Monte Carlo simulations and Sobol’ indices. Uncertainties are commonly associated with the material and geometrical properties of the pipe along with the surrounding soil characteristics. However, the significance of these parameters varies depending on the type of soil in which the water pipe is buried. In clay soil, the soil-related parameter plays a crucial role compared to sandy soil and this is verified through some experimental work carried out in two water pipe systems with very different properties, one in the UK and the other one in Brazil. This research is of fundamental importance for determining the most critical parameters affecting the leak noise wave, allowing to evaluate and integrate uncertainty information into decision-making of current technologies, such as loggers and leak noise correlators, aiming enhanced detection and location of water leakage in buried plastic water pipes.

Soil Nailing Application for Railways Track Safety on Slope Area

Abstract Railways track at KM 25+100 - KM 25+200 from Jember to Banyuwangi is constructed next to slope area with inclination angle 69°. As railways track mapping report, this area is categorized as a high-potential landslide area that can harm train travel. By using soil nailing method with threaded steel and embedded into the soil for grouting, slope stabilization be improved. Undisturbed soil sampling on 1.5 m depth was carried out and tested to determine soil parameters. Based on the USCS soil classification, the soil at the site is an organic clay with high plasticity. Soil parameters are used to calculate the slope safety factor before and after soil nailing application with the best reinforcement design. By utilizing Plaxis 2D CE V20 Bentley software and manual calculations with the bishop method for comparison, the potential landslide before reinforcement resulted a safety factor value of 1.198 by using Plaxis and 0.97 by calculated manually. Some soil nailing reinforcement planning design is obtained and resulted that soil nailing design with diameter 29 mm, slope angle application on 20° with distance between nail bar at 1m, and nail length 9m have best safety factor value at 1.548. With the best design and >1.5 SF value, the soil nailing design is safe against landslides risk.

Considering the changes in unsaturated soil saturation after pipeline leakage: A modified Terzaghi model

Pipeline leakage leads to the saturation and weakening of the surrounding soil, increasing the pressure exerted by the overlying soil on underground engineering structures and posing a serious threat. Therefore, it is necessary to thoroughly understand the influence of pipeline leakage on the overlying soil pressure. Based on the saturation distribution within different diffusion ranges, an analysis model for pressure in loose soil under the influence of pipeline leakage was presented. Considering the variation in the matric suction of the unsaturated soil, the soil pressure can be modeled based on the incomplete arch effect. The influence of the relevant parameters on the overlying soil pressure was analyzed, and the accuracy and rationality of the modified model were verified using a trapdoor test. These findings indicate that the modified model can accurately estimate the soil pressure caused by a pipeline leakage. The overlying soil pressure is directly proportional to the diffusion distance, tunnel width, and slip surface inclination angle and inversely proportional to the relative deformation. The rate of change was mainly influenced by the parameters affecting the soil arching effect. The modified model presented in this study can be used to directly calculate the overlying soil pressure affected by pipeline leakage. This calculation is based on the known physical and mechanical parameters of unsaturated soil, pipeline leakage range, and relative deformation of the tunnel, thus providing a theoretical basis for the design of structures under urban pipelines.

Dynamics of Physical Parameters of Soils of the Meadow Series in the Kamennaya Steppe

Dynamics of Physical Parameters of Soils of the Meadow Series in the Kamennaya Steppe

Litter decomposition and nutrient dynamics in a subtropical ecosystem: A comparison of natural and plantation forests (Duabanga grandiflora) in Nagaland, North-East India

Litter decomposition and nutrient dynamics in a subtropical ecosystem: A comparison of natural and plantation forests (Duabanga grandiflora) in Nagaland, North-East India