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Pile penetration in soft ground involves complex mechanisms, including significant alterations in the soil state surrounding the pile, which influence the pile negative skin friction (NSF) over time. However, the pile penetration process is often excluded from finite element analysis. This paper investigates the impact of pile penetration on the generation of NSF and dragload. A stable node-based smoothed particle finite element method (SNS-PFEM) framework is introduced for two-dimensional axisymmetric conditions and coupled consolidation, incorporating the ANICREEP model of soft soil with a modified cutting-plane algorithm. A field case study with penetration process is simulated to verify the numerical model's performance, followed by a parametric analysis on the effect of penetration rate on NSF during consolidation. Results indicate that without the pile penetration process in NSF analysis can result in an unsafely low estimation of NSF and dragload magnitudes. The penetration rate affects dragload only at the initial consolidation stage. As consolidation progresses, dragload converges to nearly the same magnitude across different rates. Additionally, current design methods inadequately predict the beta value (where beta is an empirical factor correlating vertical effective stress of soil with the pile skin friction) and its time dependency, for which a new empirical formula for the time-dependent beta value is proposed and successfully applied to other field cases.

期刊论文 2025-09-01 DOI: 10.1016/j.compgeo.2025.107315 ISSN: 0266-352X

The brick walls of ancient buildings have got a lot of tiny and closely connected pores inside, so they can soak up water really well. This can easily cause problems like getting powdery and having efflorescence. To stop water from spoiling the grey bricks, this paper focuses on the brick walls of historical buildings in Kaifeng City. Based on our investigation, we study the distribution features of the problems. This paper tells about using the method of negative pressure infiltration to change the grey bricks. We measure all kinds of basic indicators and analyze how different ratios of modifiers affect the water properties and dry-wet cycle tests of the grey bricks. We look at the changes in the inside shape through SEM to show how it changes the grey bricks of ancient buildings. Second, we improve the wet walls by using a way that combines blocking and drainage. The main things we studied and the conclusions are like this: We use sodium methyl silicate and acrylamide polymer as modifiers to soak the historical grey bricks under negative pressure. We figure out the best ratio through orthogonal experiments. We analyze things like the water vapor permeability, how long it takes for a water drop to go through, the compressive strength, the water absorption rate, and the height of water absorption of the modified bricks. The results show that the crosslinking agent and acrylamide monomer have a big influence on how high the capillary water goes up in the modified bricks. The air permeability of the modified grey bricks with acrylamide polymer goes down a bit, but it's still okay. The surface of the modified grey bricks is very hydrophobic and there are fewer pores inside. The mechanical properties of the modified grey bricks get better in different degrees. The water absorption rate and the height of capillary water absorption go down. The modified grey bricks can really cut down the erosion of water on the wall when used in real life. They can reduce salt crystallization and efflorescence caused by rising water, and so make the brick walls of historical buildings last longer. This is super important for protecting historical buildings in Kaifeng City and taking care of other similar structures. Also, by using a way that combines blocking and drainage, and putting polymer infiltration reinforcement and the ventilation of the moisture drainage pipe together, the results show that this combination can really lower the height that capillary water goes up in the brick wall. So we get a way to control how wet the wall is.

期刊论文 2025-07-01 DOI: 10.1016/j.cscm.2025.e04422 ISSN: 2214-5095

This study investigates the pore water pressure (PWP) behavior of soil around large-diameter open-ended thin- walled piles (LOTPs) during impact driving using a large deformation finite-element method. A comparative analysis of the PWP accumulation curves of the soil inside, outside, and below the LOTP tips with different diameters and wall thicknesses during impact driving is conducted under the same hammering solution. The PWP development is dependent on the absolute distance from the pile surface to the location of the soil and the dimensions of the LOTP. The excess pore water pressure (EPWP) accumulates and gradually dissipates, and its level decreases with increasing pile diameter. However, a negative excess pore water pressure (Ne-EPWP) is identified during hammering. Based on the above findings and analyses, a PWP prediction equation for LOTP during driving is proposed, and the predicted curves are compared with the numerical results. The influence of PWP accumulation after penetration of 2d (d is the LOTP internal diameter) does not increase significantly. This equation can provide the initial distribution field of PWP in saturated clay for LOTPs, thereby facilitating pile drivability analyses.

期刊论文 2025-04-01 DOI: 10.1016/j.compgeo.2025.107065 ISSN: 0266-352X

Winter extreme low temperature events have been occurring frequently both before and after the winter season. The freezing resistance temperature of wheat is far lower than the intensity of low temperatures during the mid-winter period. Therefore, it is necessary to further quantify and evaluate the impact of low-temperature periods and durations during the early winter and the green-up period on the freezing resistance of wheat, based on different evaluation indicators. Through conducting experiments in an artificial low-temperature control chamber, this study investigates the critical temperature thresholds for the impact of different low-temperature periods and durations on the tiller and yield of winter wheat, as well as the critical temperature thresholds for soil effective negative accumulated temperature. The results demonstrate that (1) the tiller mortality rate (RT) and yield reduction rate (RY) of winter wheat during the winter increase with the severity and duration of low temperatures, showing an S-shaped curve. The winter wheat mortality rate during the early winter is related to the soil effective negative accumulated temperature in an exponential function, while the mid-winter and green-up stages have a linear relationship. (2) The freezing threshold temperatures for the RT, RY and soil negative accumulated temperature (SENAT) in different low-temperature periods (early winter, mid-winter, and green-up periods) range from - 11.7 to -17.9 degrees C, -9.4 to -15.6 degrees C, and 15.9 to 131.7 degrees Ch (2.2 to 16.8 degrees Cd), respectively. (3) The freezing threshold temperatures for the RT and RY in different low-temperature durations (1 day, 2 days, and 3 days) range from - 2.8 to -17.9 degrees C and - 9.4 to -15.6 degrees C, respectively. The findings of this study provide technical support and scientific guidance for the global cultivation structure and variety layout of winter wheat under the background of climate warming, as well as for the prevention and reduction of freezing damage and yield losses.

期刊论文 2025-03-12 DOI: 10.1038/s41598-025-93019-z ISSN: 2045-2322

Non-point source pollution resulting from agricultural fertilization may enter neighboring water bodies, negatively impacting the environmental water quality. Therefore, this study aims to evaluate the efficiency of innovative fertilization strategies for agricultural non-point source pollution control and explore their benefit for carbon negativity. The results show that organic fertilizers are more likely to be washed out by rainfall or irrigation due to their higher soluble component content. The treatments using bamboo biochar, microbial agents, or both significantly reduced the nitrogen concentrations in infiltration and surface runoff. The washedaway phosphate demonstrated a different trend because adding microbial agents, including phosphorussolubilizing bacteria, converted fixed inorganic phosphorus in the soil into water-soluble phosphorus. In addition, the scouring and leaching in rainfall events mainly cause the farmland's nutrient loss after fertilizer application. The nutrient uptake by crops was increased by 15-30 %, and nutrient mass in infiltration and runoff waters was reduced by 5-10 %. By combining fertilizer reduction and innovative fertilization strategies, the crop yield remained similar to that with a full amount of fertilizer application. Over-dose application in fertilizer may not necessarily promote crop growth but may cause crop damage and fertilizer loss. The carbon negativity benefit of using innovative fertilization strategies was explored, and adding both microbial agents and bamboo biochar in half organic fertilization demonstrated the highest reduction (80.75 %) in carbon emission through synergistic interactions in the soil matrix. The innovative fertilization strategies employed in this study can (1) effectively reduce non-point source pollution from agricultural activities without impairing crops' overall growth and yield and (2) induce the synergistic effects in reducing nutrient loss, enhancing soil carbon sequestration, and mitigating greenhouse gas emissions.

期刊论文 2025-02-01 DOI: 10.1016/j.agwat.2024.109270 ISSN: 0378-3774

The bending and damage suffered by the pipelines during the upward movement depend largely on the displacement of the pipe and the damage degree of the surrounding soil. According to the failure mechanism of the surrounding soil caused by the upward movement of pipelines, this paper described the shear plane development of the uplifting load-displacement curve (LDC) across varying phases. However, the existing LDC model is not able to accurately calculate the change in overlying load during pipeline upward. Hence, to precisely determine the uplifting load of the pipeline, a composite power-exponential function (CPEF) is proposed. Additionally, modifications have been made to the calculation formula for the residual uplifting load. The proposed CPEF comprises four parameters: a , b , c , and d . To verify the validity of the proposed CPEF model, the experimental results are compared with the calculated results of the proposed CPEF, which show that the proposed CPEF model can well predict the entire process of uplifting load changes on the pipeline during the upward movement process. Finally, the influence of parameters on the LDC calculated by CPEF under the same conditions was analyzed by varying the parameters of CPEF.

期刊论文 2025-01-01 DOI: 10.1139/cgj-2024-0063 ISSN: 0008-3674

The article examines various aspects of establishing factual circumstances in cases related to the pollution of soil-origin objects (using the example of the use of livestock by-products as fertilizers). The results of the analysis of law enforcement practice in cases of this category are presented.

期刊论文 2025-01-01 ISSN: 2218-5194

Terrestrial enhanced rock weathering (ERW) is a promising carbon dioxide removal technology that consists in applying ground silicate rock such as basalt on agricultural soils. On top of carbon sequestration, ERW has the potential to raise the soil pH and release nutrients, thereby improving soil fertility. Despite these possible co-benefits, concerns such as heavy metal pollution or soil structure damage have also been raised. To our knowledge, these contrasted potential effects of ERW on soil fertility have not yet been simultaneously investigated. This field trial aimed at assessing the impact of ERW on biological, physical, and chemical soil properties in a temperate agricultural context. To do so, three vineyard fields in Switzerland were selected for their distinct geochemical properties and were amended with basaltic rock powder at a dose of 20 tons per hectare (2 kg.m(-2)). On each field, basaltic rock powder was either applied one year before the sampling campaign, one month before the sampling campaign, or not applied (control) for a total of 27 plots with 9 repetitions of each level. Overall, basaltic rock powder addition had a predominantly positive to neutral effect on soil fertility. Most soil properties showed no significant change either 1 month or 1 year post application. Nevertheless, our study highlighted a significant increase in earthworm abundance (+71 % on average), soil respiration (+50 %) and extractable sodium concentration (+23 %) as early as 1 month post application. The higher soil respiration raises the question of CO2 losses from organic matter mineralization that could limit ERW's efficiency. The increase in sodium raises concerns about a sodification risk potentially damaging soil fertility. These elements now require further investigation before enhanced rock weathering can be considered a viable and secure carbon dioxide removal technology.

期刊论文 2024-12-01 DOI: 10.1016/j.scitotenv.2024.176297 ISSN: 0048-9697

Local site effects play a vital role in determining the level of structural damage to the structures built on soil. Therefore, correctly determining the underground layer structure and its physical characteristics in the lateral and vertical directions is essential for the geotechnical model. More information and more accurate results will be obtained if the geotechnical model is evaluated multidisciplinary together with geophysical studies, not only based on drilling results. For this purpose, vertical electric sounding, seismic refraction, microtremor, and mechanical drilling techniques were applied within the scope of geotechnical studies in the & Idot;neg & ouml;l district of Bursa. The methods were evaluated together, and the geotechnical cross-sections of the underground were interpreted. In addition, microzonation maps determined from Geophysical parameters were created in the study area. These maps, geotechnical cross-sections, and microtremor data evaluation results predicted how the study area's buildings and soils would behave under dynamic forces such as earthquakes. As a result, the soils in the study area were mainly saturated with water and had weak strength. Existing or newly constructed engineering structures on such soils are predicted from microzonation maps that will damage both the soils and the buildings in a seven-magnitude earthquake.

期刊论文 2024-11-01 DOI: 10.1029/2023EA003460

The durability of small-diameter larch wood was studied with respect to its treatments with wood tar and wood vinegar in three environments- underground, underwater, and outdoors-for 53 months. This study involved assessing wood cell wall deterioration using optical microscopy, X-ray computed tomography imaging, and X-ray diffraction, along with evaluating various physical and mechanical properties using Korean standards. Severe deterioration was observed in vinegar-treated sapwood after being buried underground. Collapsed cells were often found in untreated and wood vinegar-treated wood buried underground. Noticeable decreases in the physical and mechanical properties were observed in the sapwood of wood vinegar-treated wood buried underground. The wood tar-treated wood buried underground remained relatively intact with minimal changes in its physical properties. No significant degradation was observed in the wood discs submerged in water, and there was no difference in density, shrinkage, hardness, and shear strength between the untreated and preserved wood submerged in water. Under outdoor conditions, wood vinegar-treated wood showed less degradation of the wood discs than untreated and wood tar-treated wood. In conclusion, wood tar enhanced the durability of the wood when it was buried in soil, whereas the wood vinegar treatment provides an advantage when exposed to outdoor conditions.

期刊论文 2024-11-01 DOI: 10.15376/biores.19.4.7946-7962 ISSN: 1930-2126
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