scholarly journals Study on Permeability of Steel Slag and Steel Slag Modifying Silt Soil as New Geo-Backfill Materials

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Liyan Wang ◽  
Jiatao Yan ◽  
Qi Wang ◽  
Binghui Wang ◽  
Aimable Ishimwe
Keyword(s):  
Relative Density ◽  
Permeability Coefficient ◽  
Steel Slag ◽  
Fine Sand ◽  
Particle Analysis ◽  
Physical Parameters ◽  
Permeability Coefficients ◽  
Variable Head ◽  
Backfill Materials ◽  
Constant Head

To make steel slag being reasonably used in geotechnical backfilling projects or soft foundation treatment projects, three kinds of steel slag such as fine, coarse, and gravel steel slag were studied through particle analysis tests, relative density tests, and specific gravity tests to obtain basic physical parameters. Considering the influence of relative density, gradation, and other factors, constant head permeability tests of pure steel slag and variable head permeability tests of modified silt soil with different mixing contents of steel slag were carried out to test permeability coefficients under various working conditions. Prediction formulas on the permeability coefficients of the three kinds of pure steel slag and steel slag-treated silt soil were, respectively, deduced. It was concluded that the permeability coefficient of pure steel slag was greatly influenced by particle size and relative density, similar to the case of permeability coefficients of fly ash and fine sand in their dense states, and the larger the relative density was, the smaller the permeability coefficient was. The permeability coefficient of steel slag-treated silt soil increased with increasing of mixing content of steel slag, showing that steel slag can obviously improve the permeability performance of silt soil. Research results provide reference for design and construction on the application of steel slag in roadbed backfill, steel slag modifying silt soil, and other projects.

scholarly journals Caracterização de parâmetros hidráulicos em depósitos fluviais paleogênicos na Bacia de Volta Redonda, RJ

2007 ◽  
Vol 30 (2) ◽  
pp. 118-132
Author(s):  
Ana Carolina Lisbôa Barboza ◽  
Gerson Cardoso da Silva Jr ◽  
Claudio Limeira Mello
Keyword(s):  
Hydraulic Conductivity ◽  
Sedimentary Facies ◽  
Fine Sand ◽  
Sedimentary Deposits ◽  
Hydrogeological Parameters ◽  
Variable Head ◽  
Medium Reservoir ◽  
Maximum Permeability

The present study aims for the characterization of the hydrogeological parameters of the Paleogenic fluvial deposits of Volta Redonda Geological Basin, through hydraulic conductivity determinations and grain sized analyses. The overall goal was to produce a hydrogeological data base applicable to the characterization of hydrofacies (interconnected sedimentary bodies with distinct hydraulic properties) and the modeling groundwater flow. The used methods used consisted of in situ permeability determinations (Guelph permeameters) and laboratory tests (variable head permeameter), besides grain size analyses carried out in each sedimentary facies in the study area. These sedimentary facies were characterized by Marques (2006) and belong to the Resende and Pinheiral formations. The permeameter results were coherent to the sedimentological characteristics. The Resende Formation sedimentary deposits are constituted by medium to fine sand with presence of argillaceous matrix and present moderate to very low hydraulic conductivity, varying between 10-4 to 10-8 cm/s, which indicates a poor reservoir. The Pinheiral Formation presents sandy layers with conglomeratic lenses, limited by small thickness pelitic intervals, with a very low permeability, with a hydraulic conductivity varying between 10-5 to 10-7 cm/s. The upper layer has the maximum permeability, around 10-3 cm/s. This formation presents a medium reservoir characteristics and it must be taken into consideration that the upper layer has as role in recharge to the aquifer. From the results of hydraulic conductivity, that varies from 10-8 to 10-3 cm/s for the Resende and Pinheiral formations, it is concluded that these deposits a low to medium hydraulic conductivity, explaining the low productivity of the water-bearing multilayered aquifer of Volta Redonda Basin.

Arching effect in fine sand due to base yielding

2010 ◽  
Vol 47 (3) ◽  
pp. 366-374 ◽  
Author(s):  
Jamshid Sadrekarimi ◽  
Alireza Abbasnejad
Keyword(s):  
Relative Density ◽  
Experimental Work ◽  
Fine Sand ◽  
Soil Mass ◽  
Flow Process ◽  
Flow Phenomenon ◽  
Dense Sand ◽  
Arching Effect ◽  
Different Diameters ◽  
Upper Boundary

This paper presents results of an experimental work on the arching effect in loose and dense sand. The apparatus comprises concentric circular trapdoors with different diameters that can yield downward while stresses and deformations are recorded simultaneously. As the trapdoor starts to yield, the whole mass of soil deforms elastically. However, after a specified displacement that depends on the trapdoor diameter and soil relative density, the soil mass behaves plastically. This behavior, which is due to flow phenomenon, continues until the stress applied onto the trapdoor decreases to a minimum value. Then the stress carried by the trapdoor shows an ascending trend. This indicates the gradual separation of the yielding mass from the whole soil body. Finally, the flow process creates a stable arch of sand. This process is called the arching mechanism. Depending on the trapdoor diameter, there is a critical relative density at and beyond which the test leads to the formation of a stable arch. The results are also compared with Terzaghi’s theory and the assumption of an upper boundary solution is discussed.

scholarly journals The Influence of Bedding Planes and Permeability Coefficient on Fracture Propagation of Horizontal Wells in Stratification Shale Reservoirs

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-19
Author(s):  
Yuepeng Wang ◽  
Xiangjun Liu ◽  
Lixi Liang ◽  
Jian Xiong
Keyword(s):  
Permeability Coefficient ◽  
In Situ Stress ◽  
Stress Difference ◽  
Strength Parameters ◽  
Breakdown Pressure ◽  
Permeability Coefficients ◽  
Bedding Planes ◽  
Initiation Pressure ◽  
Shale Reservoirs

The complexity of hydraulic fractures (HF) significantly affects the success of reservoir reconstruction. The existence of a bedding plane (BP) in shale impacts the extension of a fracture. For shale reservoirs, in order to investigate the interaction mechanisms of HF and BPs under the action of coupled stress-flow, we simulate the processes of hydraulic fracturing under different conditions, such as the stress difference, permeability coefficients, BP angles, BP spacing, and BP mechanical properties using the rock failure process analysis code (RFPA2D-Flow). Simulation results showed that HF spread outward around the borehole, while the permeability coefficient is uniformly distributed at the model without a BP or stress difference. The HF of the formation without a BP presented a pinnate distribution pattern, and the main direction of the extension is affected by both the ground stress and the permeability coefficient. When there is no stress difference in the model, the fracture extends along the direction of the larger permeability coefficient. In this study, the in situ stress has a greater influence on the extension direction of the main fracture when using the model with stress differences of 6 MPa. As the BP angle increases, the propagation of fractures gradually deviates from the BP direction. The initiation pressure and total breakdown pressure of the models at low permeability coefficients are higher than those under high permeability coefficients. In addition, the initiation pressure and total breakdown pressure of the models are also different. The larger the BP spacing, the higher the compressive strength of the BP, and a larger reduction ratio (the ratio of the strength parameters of the BP to the strength parameters of the matrix) leads to a smaller impact of the BP on fracture initiation and propagation. The elastic modulus has no effect on the failure mode of the model. When HF make contact with the BP, they tend to extend along the BP. Under the same in situ stress condition, the presence of a BP makes the morphology of HF more complex during the process of propagation, which makes it easier to achieve the purpose of stimulated reservoir volume (SRV) fracturing and increased production.

Oxygen and carbon dioxide permeability of subcutaneous pockets

1962 ◽  
Vol 202 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Hugh D. Van Liew
Keyword(s):  
Carbon Dioxide ◽  
Blood Flow ◽  
Surface Area ◽  
Uptake Rate ◽  
Permeability Coefficient ◽  
Exchange Coefficient ◽  
Adjacent Tissue ◽  
Permeability Coefficients ◽  
Tissue Tension

Uptake rate of a gas from a rat's subcutaneous gas pocket was divided by the surface area and by the apparent pocket-to-tissue tension difference to yield an exchange coefficient, K'. Values in (ml x 10–4)/(min cm2 atm) were O2, 6.6; CO2, 150; and N2, 2. Blood flow in adjacent tissue appeared to have little influence on uptakes of O2 and CO2, since the K'co2:K'o2 ratio indicated that the uptakes were governed by diffusion alone, and drastic alteration of blood flow (death of the animal) decreased K'o2 by only 10%. In contrast, blood flow apparently affected N2 uptake. Because O2 and CO2 uptakes were not blood flow limited, K'o2 and K'co2 are estimates of true permeability coefficients; the calculated permeability coefficient for N2 is 3.3 (ml x 10–4)/(min cm2 atm). Comparison shows the pocket surface to be 1/50–1/150 as effective for O2 transfer as the lung. Finally, corrections are calculated for pocket-to-tissue pO2 and pCO2 differences in gas pockets used for tissue tonometry.

scholarly journals Stability Analysis of Hydrodynamic Pressure Landslides with Different Permeability Coefficients Affected by Reservoir Water Level Fluctuations and Rainstorms

Water ◽  
2017 ◽  
Vol 9 (7) ◽  
pp. 450 ◽  
Author(s):  
Faming Huang ◽  
Xiaoyan Luo ◽  
Weiping Liu
Keyword(s):  
Water Level ◽  
Permeability Coefficient ◽  
Hydrodynamic Pressure ◽  
Water Level Fluctuations ◽  
Reservoir Water ◽  
Reservoir Water Level ◽  
Stability Coefficient ◽  
Permeability Coefficients ◽  
Landslide Stability ◽  
The Stability

It is significant to study the variations in the stability coefficients of hydrodynamic pressure landslides with different permeability coefficients affected by reservoir water level fluctuations and rainstorms. The Sifangbei landslide in Three Gorges Reservoir area is used as case study. Its stability coefficients are simulated based on saturated-unsaturated seepage theory and finite element analysis. The operating conditions of stability coefficients calculation are reservoir water level variations between 175 m and 145 m, different rates of reservoir water level fluctuations, and a three-day continuous rainstorm. Results show that the stability coefficient of the hydrodynamic pressure landslide decreases with the drawdown of the reservoir water level, and a rapid drawdown rate leads to a small stability coefficient when the permeability coefficient ranges from 1.16 × 10−6 m/s to 4.64 × 10−5 m/s. Additionally, the landslide stability coefficient increases as the reservoir water level increases, and a rapid increase in the water level leads to a high stability coefficient when the permeability coefficient ranges from 1.16 × 10−6 m/s to 4.64 × 10−5 m/s. The landslide stability coefficient initially decreases and then increases as the reservoir water level declines when the permeability coefficient is greater than 4.64 × 10−5 m/s. Moreover, for structures with the same landslide, the landslide stability coefficient is most sensitive to the change in the rate of reservoir water level drawdown when the permeability coefficient increases from 1.16 × 10−6 m/s to 1.16 × 10−4 m/s. Additionally, the rate of decrease in the stability coefficient increases as the permeability coefficient increases. Finally, the three-day rainstorm leads to a significant reduction in landslide stability, and the rate of decrease in the stability coefficient initially increases and then decreases as the permeability coefficient increases.

Predicting of Permeability Coefficient for Compacted Clay

2013 ◽  
Vol 405-408 ◽  
pp. 571-575
Author(s):  
Dong Qin Ran ◽  
Ji Ru Zhang
Keyword(s):  
Analytical Method ◽  
Permeability Coefficient ◽  
Compacted Clay ◽  
Water Release ◽  
Permeability Coefficients ◽  
Nonlinear Trend

Permeability coefficients of three compacted clay samples are measured by using Transient Water Release and Imbitions Method which is shortly named as TRIM. The curve between permeability coefficient and suction is obtained, the results of tests show that the permeability coefficient decreases in nonlinear trend along with the increasing of suction. Based on Brooks Corey model and Mualem model which is shortly named as BCM model, an analytical method is put forward to calculate the permeability coefficient of compacted clay. The results of using BCM model and TRIM are compared, which show that the permeability coefficient obtained with two kinds of methods match well when the suction is greater than the inlet value.

A Study on the Impermeability of Composite Clay of Sanitary Landfill in Loess Area

2013 ◽  
Vol 281 ◽  
pp. 607-614 ◽  
Author(s):  
Jian Feng Gou ◽  
Zheng Zhong Zeng ◽  
Hao Lei Guo ◽  
Hao Wang ◽  
Xiao Li Wang ◽  
...  
Keyword(s):  
Pollution Control ◽  
Permeability Coefficient ◽  
Soil Layer ◽  
Clay Content ◽  
Red Soil ◽  
National Standards ◽  
Sanitary Landfill ◽  
Loess Area ◽  
Permeability Coefficients ◽  
Compacted Loess

Through the compaction and permeability tests on loess, either natural or compacted loess can meet the requirement of the Landfill Pollution Control Standards about impermeable clay. While the compaction weathered red soil layer of the tertiary, widely distributing under the loess, whose permeability coefficient is less than 1×10-7cm/s. In this study we mixed loess with weathered red soil to obtain a new kind of composite soil, and drew a conclusion that the composite soil can meet the requirements of Chinese national standards. When the clay content of composite soil reached 21%, the permeability coefficients are generally able to meet the requirement.

scholarly journals Numerical investigation of particle motion at the steel—slag interface in continuous casting using VOF method and dynamic overset grids

2022 ◽  
Author(s):  
Xiaomeng Zhang ◽  
Stefan Pirker ◽  
Mahdi Saeedipour
Keyword(s):  
Particle Motion ◽  
Particle System ◽  
Particle Density ◽  
Steel Slag ◽  
Physical Parameters ◽  
Slag Particle ◽  
Dynamic Overset Grids ◽  
Capillary Interactions ◽  
Speed Up ◽  
A Minor

AbstractThe capillary interactions are prominent for a micro-sized particle at the steel—slag interface. In this study, the dynamics of a spherical particle interacting with the steel—slag interface is numerically investigated using the volume of fluid method in combination with the overset grid technique to account for particle motion. The simulations have shown the particle’s separation process at the interface and successfully captured the formation and continuous evolution of a meniscus in the course of particle motion. A sensitivity analysis on the effect of different physical parameters in the steel—slag—particle system is also conducted. The result indicates that the wettability of particle with the slag phase is the main factor affecting particle separation behavior (trapped at the interface or fully separated into slag). Higher interfacial tension of fluid interface and smaller particle size can speed up the particle motion but have less effect on the equilibrium position for particle staying at the interface. In comparison, particle density shows a minor influence when the motion is dominated by the capillary effect. By taking account of the effect of meniscus and capillary forces on a particle, this study provides a more accurate simulation of particle motion in the vicinity of the steel—slag interface and enables further investigation of more complex situations.

Détermination au champ de la conductivité hydraulique saturée à l'aide de l'infiltromètre à charge constante de Côté: théorie et approximations mathématiques

1991 ◽  
Vol 71 (1) ◽  
pp. 119-126 ◽  
Author(s):  
O. Banton ◽  
D. Côté ◽  
M. Trudelle
Keyword(s):  
Hydraulic Conductivity ◽  
Key Words ◽  
Groundwater Table ◽  
Physical Parameters ◽  
Large Area ◽  
Conductivité Hydraulique ◽  
Potential Sources ◽  
Constant Head ◽  
A Charge ◽  
High Level

Saturated hydraulic conductivity is one of the most difficult physical parameters of soil to measure. The most accurate methods are those used in the field in the presence of a groundwater table. However, in many cases, these cannot be used, primarily when no groundwater table is present. The Côté constant head infiltrometer method proves useful in such cases, because the measurement is made on soil which is not necessarily saturated beforehand. The constant head of water used by the infiltrometer is low (3.5 cm), and so representative of precipitation and irrigation conditions. The device (which is 10 cm in diameter) performs the measurement on a large area of soil (roughly 200 cm2), and can therefore integrate varying heterogeneity and macroporosity, rendering the measurement more reliable and representative. The quantity of water needed for a measurement is about 1 L, making operation in the field easier. The Côté constant head infiltrometer is an unsophisticated device which is easy to use. Different mathematical approximations of the saturated flow of water around the infiltometer are described according to the various forms of flow taken into account. The corresponding coefficients may be used to quickly determine this parameter with a high level of confidence. However, one problem and some potential sources of error remain in the evaluation of hydraulic conductivity in the field, due principally to cases in which the soil is not totally saturated, to compaction or smoothing of the hole during digging, and to the variability of the parameter on the site. Key words: Hydraulic conductivity, infiltrometer, permeameter

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