Engineering Characteristics of Natural Wide Grading Gravelly Soil in Construction of Extra-High Earth-Rockfill Dam

CONVERTER ◽

10.17762/converter.52 ◽

2021 ◽

pp. 209-218

Author(s):

Zhan Zhenggang, Et al.

Keyword(s):

Particle Size ◽

Test Results ◽

Soil Material ◽

Numerical Tests ◽

Engineering Characteristics ◽

Rockfill Dam ◽

Gravelly Soil ◽

Gravel Soil ◽

Gravelly Soils ◽

At Home

Wide grading gravelly soil is an advantageous anti-seepage material in construction of high earth-rock dam. From the experience of earth-rockfill dam construction at home and abroad, it is more and more common to use wide grading gravelly soils such as moraine soil, weathered rock and gravel soil as anti-seepage material in construction of high earth-rockfill dams. Regarding the engineering characteristics of natural wide grading of soil material for 300m core-wall earth-rockfill dams in this paper, a series of physical and numerical tests were carried out to study its permeability and mechanical properties. By comparing the characteristics of impermeable soil materials of the projects already built and to be built at home and abroad, the preliminary indicators of impermeable soil materials are as follows: 1) Combined with the existing engineering experience and test results, the content of particles with particle size greater than 5mm should be neither over 50% nor lower than 30%. The content of particles with particle size less than 0.075mm should not be less than 15%; the content of clayey particles with particle size less than 0.005mm should not be less than 6%. 2) It is appropriate to control the permeability coefficient of impermeable soil material at less than 1×10-5cm/s.

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Effect of freeze–thaw cycles on the deformation behavior of gravelly soil in the 300 m-high earth core rockfill dam

Environmental Earth Sciences ◽

10.1007/s12665-021-09608-4 ◽

2021 ◽

Vol 80 (8) ◽

Author(s):

Feng Ming ◽

Xiu-Ling Ren ◽

Jin-guo Wang ◽

Zhi-wei Zhou ◽

En-Long Liu ◽

...

Keyword(s):

Deformation Behavior ◽

Freeze Thaw ◽

Earth Core ◽

Rockfill Dam ◽

Gravelly Soil ◽

Core Rockfill Dam

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Space Charge Property of Polyethylene/Silica Nanocomposites at Different Elongations

Journal of Nanomaterials ◽

10.1155/2015/963960 ◽

2015 ◽

Vol 2015 ◽

pp. 1-14 ◽

Cited By ~ 1

Author(s):

Can Wang ◽

Youyuan Wang ◽

Peng Fan ◽

Ruijin Liao

Keyword(s):

Particle Size ◽

Space Charge ◽

Dipole Model ◽

Particle Sizes ◽

Test Results ◽

Silica Nanocomposites ◽

Induced Dipole ◽

Interface Characteristics ◽

Space Charge Distribution ◽

Charge Property

This paper prepares polyethylene/silica nanocomposites with concentrations of 3 wt% and 5 wt% by using silicon dioxide (SiO2) nanopowder (nanosilica) with particle sizes of 15 and 50 nm. Samples whose elongations are 3%, 6%, and 10% are prepared. Pulsed electroacoustic technique is applied to evaluate the space charge distribution in samples. Test results show that homocharge near electrodes is generated in the polyethylene/silica nanocomposites. Nanocomposites with a nanoparticle concentration of 3 wt% and particle size of 15 nm suppress the accumulation of space charge effectively. The amount of space charge in the samples increases with the increase in elongation. At an elongation of 10%, packet-like space charge is generated in polyethylene/silica nanocomposites with the concentration of 5 wt% and particle sizes of 15 and 50 nm. The packet-like space charge in nanocomposites whose particle size is 50 nm is more obvious than that in nanocomposites whose particle size is 15 nm. The experiment results are explained by applying interface characteristics, dipole model, and induced dipole model.

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The variability in soil particle size test results by various subsampling techniques

Journal of Soil Science ◽

10.1111/j.1365-2389.1984.tb00255.x ◽

1984 ◽

Vol 35 (1) ◽

pp. 23-26

Author(s):

R. B. SMITH ◽

D. N. PRATT

Keyword(s):

Particle Size ◽

Soil Particle ◽

Test Results ◽

Soil Particle Size

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Optimal Physical Pretreatment Conditions for the Release of Carbohydrate and Protein from Dairy Manure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.291-294.383 ◽

2013 ◽

Vol 291-294 ◽

pp. 383-389

Author(s):

Jian Ping Sun ◽

Jun Zhu

Keyword(s):

Particle Size ◽

Experimental Design ◽

Optimum Condition ◽

Reaction Temperature ◽

Organic Materials ◽

Dairy Manure ◽

Physical Factors ◽

Test Results ◽

Release Rates ◽

Pretreatment Conditions

Various physical factors including particle size, pH, temperature and so on may influence the release of organic materials from dry dairy manure. The effect of these factors on release of protein and carbohydrate was investigated in this study using Box-Behnken Experimental Design with three factors (particle size, temperature and pH) at three levels. Test results suggested that particle size of 0.15-0.25 mm accounted for almost half of the dry manure particles and the optimum condition for release of protein and carbohydrate were pH 2, particle size 1.0-1.4 mm under reaction temperature of 90 oC, under which the protein and carbohydrate release rates could reach 1570.57 and 2813.29 mg l-1, respectively. The degree to which these factors affected organics release was in the order from high to low of temperature > particle size > pH.

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Numerical analysis of the anti-seepage measures for high earth rockfill dam on deep overburden

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.1872 ◽

2012 ◽

Vol 170-173 ◽

pp. 1872-1877 ◽

Cited By ~ 1

Author(s):

Jun Yan ◽

Si Hong Liu ◽

Bin Zhou

Keyword(s):

Finite Element ◽

Numerical Analysis ◽

Seepage Field ◽

Seepage Analysis ◽

The Real ◽

Rockfill Dam ◽

The Stability ◽

High Rockfill Dam ◽

At Home

The anti-seepage measures of a high earth rockfill dam built on the foundation with a deep overburden affects the stability and safety of the dam greatly. Nowadays there are few researches on this area both at home and abroad. On the basis of the finite element seepage analysis of the Pubugou high rockfill dam in which core walls and two cut-off walls are designed as the anti-seepage measures, the real seepage behavior of the seepage field is obtained in this paper, as well as the seepage characters of the seepage field under different arrangements of the cut-off walls. The conclusions have a certain referential value for the design of the anti-seepage measures for the similar projects with the foundation of a deep overburden.

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Using Genetic Algorithms to Set Target Values for Engineering Characteristics in the House of Quality

Volume 2: 19th Computers and Information in Engineering Conference ◽

10.1115/detc99/cie-9088 ◽

1999 ◽

Author(s):

Patricia Brackin ◽

Jonathan Colton

Keyword(s):

Genetic Algorithm ◽

Genetic Algorithms ◽

Penalty Functions ◽

Preliminary Design ◽

Test Results ◽

House Of Quality ◽

Design Specifications ◽

Engineering Characteristics ◽

Target Values

Abstract As part of a strategy for obtaining preliminary design specifications from the House of Quality, genetic algorithms were used to generate and optimize preliminary design specifications for an automotive case study. This paper describes the House of Quality for the automotive case study. In addition, the genetic algorithm chosen, the genetic coding, the methods used for mutation and reproduction, and the fitness and penalty functions are descrobed. Methods for determining convergence are examined. Finally, test results show that the genetic algorithm produces reasonable preliminary design specifications.

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SYNTHESIS AND STABILITY OF RESVERATROL-CONJUGATED GOLD NANOPARTICLES MODIFIED WITH POLYETHYLENE GLYCOL

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2020.v12s1.ff050 ◽

2020 ◽

pp. 230-236

Author(s):

RADITYA ISWANDANA ◽

RICHA NURSELVIANA ◽

SUTRIYO SUTRIYO

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Polyethylene Glycol ◽

Zeta Potential ◽

High Performance ◽

Entrapment Efficiency ◽

Test Results ◽

Novel Method ◽

The Stability ◽

Phosphate Buffered Saline

Objective: Gold nanoparticles (AuNPs) are highly useful for drug delivery, but their application is limited by their stability as they readily aggregate.This issue can be prevented by adding a stabilizing agent such as resveratrol (RSV), which is a polyphenol derived from plants, that is used to preventcancer. Therefore, we propose a novel method to prepare stable RSV-conjugated nanoparticles modified with polyethylene glycol (RSV-AuNP-PEG).Methods: In the first step, the Turkevich method was used to synthesize the AuNPs. Then, PEG was added as stabilizer agent and conjugated with RSV.The synthesized conjugates were characterized using ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy, particle sizeanalysis, and high-performance liquid chromatography.Results: The obtained RSV-AuNP-PEG had a particle size of 83.93 nm with a polydispersity index (PDI) of 0.562 and formed a translucent purple-redfluid in solution. The zeta potential was −22.9 mV, and the highest entrapment efficiency was 75.86±0.66%. For comparison, the RSV-AuNP solutionwas purple and turbid, the particle size was 51.97 nm with a PDI of 0.694, and the zeta potential was −24.6 mV. The stability test results showed thatthe storage stability of RSV-AuNP-PEG was better than that of AuNP-RSV. Further, the RSV-AuNP-PEG was shown to be most stable in 2% bovine serumalbumin (BSA) while the AuNP-RSV was most stable in 2% BSA in phosphate-buffered saline pH 7.4.Conclusion: These results show that modification of RSV-conjugated AuNPs with PEG effectively prevents their aggregation in storage, but only incertain mediums.

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Effect of Slag Particle Size on Fracture Toughness of Concrete

Applied Sciences ◽

10.3390/app9040805 ◽

2019 ◽

Vol 9 (4) ◽

pp. 805 ◽

Cited By ~ 3

Author(s):

Chung-Ho Huang ◽

Chung-Hao Wu ◽

Shu-Ken Lin ◽

Tsong Yen

Keyword(s):

Fracture Toughness ◽

Particle Size ◽

Compressive Strength ◽

Stress Intensity ◽

Fracture Energy ◽

Critical Stress ◽

Critical Stress Intensity Factor ◽

Cementitious Material ◽

Test Results ◽

Unique Effect

The effects of particle size of ground granulated blast furnace slag (GGBS) on the fracture energy, critical stress intensity, and strength of concrete are experimentally studied. Three fineness levels of GGBS of 4000, 5000, 6000 cm2/g were used. In addition to the control mixture without slag, two slag replacement levels of 20% and 40% by weight of the cementitious material were selected for preparing the concrete mixtures. The control mixture was designed to have a target compressive strength at 28 days of 62 MPa, while the water to cementitious material ratio was selected as 0.35 for all mixtures. Test results indicate that using finer slag in concrete may improve the filling effect and the reactivity of slag, resulting in a larger strength enhancement. The compressive strength of slag concrete was found to increase in conjunction with the fineness level of the slag presented in the mixture. Use of finer slag presents a beneficial effect on the fracture energy (GF) of concrete, even at an early age, and attains a higher increment of GF at later age (56 days). This implicates that the finer slag can have a unique effect on the enhancement of the fracture resistance of concrete. The test results of the critical stress intensity factor (KSIC) of the slag concretes have a similar tendency as that of the fracture energy, indicating that the finer slag may present an increase in the fracture toughness of concrete.

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Application of laser diffraction method for determination

Research in Agricultural Engineering ◽

10.17221/2133-rae ◽

2008 ◽

Vol 53 (No. 1) ◽

pp. 34-38 ◽

Cited By ~ 5

Author(s):

M. Ryzak ◽

A. Bieganowski ◽

R.T. Walczak

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Podzolic Soil ◽

Diffraction Method ◽

Laser Diffraction ◽

Soil Material ◽

New Methods ◽

Particle Size Distribution Measurement ◽

Straight Lines

Particle size distribution affects many physical soil properties and processes taking place in soil. There are many methods to determine the particle size distribution. The most frequently used are the sieve, sieve-pipette and sedimentation methods. Technological progress in electronics permitted a wide use of new methods of particle size distribution measurement in soil, e.g. the laser diffraction method. A comparison of particle size distribution obtained with the universally used areometer method (Cassagrande, modified by Prószynski) with results from the laser diffraction method for soil material received from grey-brown podzolic soil is presented in this work. The largest differences between the results were obtained for the smallest fraction determined with the areometer and laser diffraction methods. In a majority of other cases the slopes of interpolated straight lines were contained within the range of 0.81 ÷ 1.09.

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