scholarly journals Using the Effective Void Ratio and Specific Surface Area in the Kozeny–Carman Equation to Predict the Hydraulic Conductivity of Loess

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 24 ◽  
Author(s):  
Bo Hong ◽  
Xi’an Li ◽  
Li Wang ◽  
Lincui Li ◽  
Quan Xue ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Permeability Coefficient ◽  
Void Ratio ◽  
Geometric Mean ◽  
Cohesive Soil ◽  
Liquid Limit ◽  
Published Data ◽  
Effective Void Ratio

Many modified Kozeny–Carman (KC) equations have been used to predict the saturated permeability coefficient (Ks) of porous media in various fields. It is widely accepted that the KC equation applies to sand but does not apply to clay. Little information is available to clarify this point. The effectiveness of the KC equation will be evaluated via laboratory penetration tests and previously published data, which include void ratio, specific surface area (SSA), liquid limit (LL), and permeability coefficient values. This paper demonstrates how to estimate the SSA of cohesive soil from its LL. Several estimation algorithms for determining the effective void ratio (ee) of cohesive soil are reviewed. The obtained results show that, compared to the KC equation based on porosity and geometric mean particle size (Dg), the KC equation based on the SSA and the ee estimation algorithm can best predict the Ks of remolded loess. Finally, issues associated with the predictive power of the KC equation are discussed. Differences between measured and the predicted Ks values may be caused by the uniformity of the reconstructed specimen or insufficient control of the test process and errors in the SSA and ee.

The relationship between geotechnical index properties and the pore-size distribution of compacted clayey silts

2015 ◽  
Vol 22 (6) ◽  
Author(s):  
Nazile Ural
Keyword(s):  
Specific Surface ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pore Volume ◽  
Correlation Coefficients ◽  
Liquid Limit ◽  
Index Properties

AbstractIn this study, the relationships between geotechnical index properties and the pore-size distribution of compacted natural silt and artificial soil mixtures, namely, silt with two different clays and three different clay percentages (10%, 20%, and 40%), were examined and compared. Atterberg’s limit tests, standard compaction tests, mercury intrusion porosimetry, X-ray diffraction, scanning electron microscopy (SEM) analysis, and Brunauer-Emmett-Teller specific surface analysis were conducted. The results show that the liquid limit, the cumulative pore volume, and specific surface area of artificially mixed soils increase with an increase in the percentage of clay. The cumulative pore volume and specific surface area with geotechnical index properties were compared. High correlation coefficients were observed between the specific areas and both the liquid limit and the plasticity index, as well as between the cumulative pore volume and both the clay percentage and the

Changes in Particle Size and Crystallinity in Ground Nickel Powder

2008 ◽  
Vol 587-588 ◽  
pp. 468-472
Author(s):  
J.M. González ◽  
José A. Rodríguez ◽  
Enrique J. Herrera
Keyword(s):  
Particle Size ◽  
Specific Surface ◽  
Crystallite Size ◽  
Surface Area ◽  
Specific Surface Area ◽  
Nickel Powder ◽  
Milling Time ◽  
High Energy ◽  
Published Data ◽  
Average Particle

Nickel powder was dry-milled using a high-energy disc-oscillating mill. The average particle size increases and the specific surface area diminishes with milling time. Crystallite size decreases and microstrains increase, under the same conditions, as shown by X-ray analysis. At 120 min milling time, the crystallite size has a value of 17 nm, i.e., a nanostructured powder, with a perturbed lattice, is obtained. The above results have been compared with published data about the effects of milling on a ceramic powder. There is, in both cases, a general agreement concerning the changes produced in crystallite size. Nevertheless, opposite results are reached regarding particle size and specific surface area.

scholarly journals The relationship between the liquid limit of clayey soils, external specific surface area and the composition of exchangeable cations / Zależność granicy płynności od zewnętrznej powierzchni właściwej i składu kationów w naturalnym kompleksie wymiennym

2012 ◽  
Vol 17 (1) ◽  
pp. 83-88 ◽  
Author(s):  
Andrzej Olchawa ◽  
Aleksandra Gorączko
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
External Surface ◽  
Exchange Capacity ◽  
Liquid Limit ◽  
Sodium Cation ◽  
Exchangeable Cations ◽  
Clayey Soils ◽  
External Surface Area

Abstract The liquid limit - wL, the external surface area - Se, the concentration of exchangeable cations - Zi and the cation exchange capacity - CEC of seventeen clayey soils were determined. Finding the correlation between the liquid limit, external specific surface area and exchangeable cation concentration was the aim of this study. Experimental study performed using soils of the external surface area within the range of 4.1 to 118.5 m2·g-1. The relative content of sodium cation (i.e. Na+/CEC) varying between 0.03 and 1.0. Obtained results point to statistically significant relationship between these three properties. The greatest predictive power of linear regression was found for soils of external specific surface area larger than 60 m2·g-1. For the soils of comparable external surface area, the liquid limit increase with increasing the ratio of the content of sodium cation to the cation exchange capacity - Na+/CEC. For the soils of comparable composition of exchangeable cations the liquid limit increase with increasing the external surface area. These relationships indicates that interparticle forces have a prominent role in determining liquid limit of clayey soils.

Probabilistic Estimation of Specific Surface Area and Cation Exchange Capacity: A Global Multivariate Distribution

2020 ◽  
Author(s):  
Atma Sharma ◽  
Budhaditya Hazra ◽  
Giovanni Spagnoli ◽  
Sreedeep Sekharan
Keyword(s):  
Specific Surface ◽  
Cation Exchange ◽  
Surface Area ◽  
Specific Surface Area ◽  
Cation Exchange Capacity ◽  
Probabilistic Approach ◽  
Clay Fraction ◽  
Exchange Capacity ◽  
Liquid Limit ◽  
Vine Copula

Specific surface area (SSA) and cation exchange capacity (CEC) are two fundamental clay properties. However, the determination of CEC and SSA is challenging due to inherent uncertainties and difficulty in experimental measurement. Popular approach is to employ transformation models for its estimation. However, most of the existing models were developed on limited sample sizes, and quantification of uncertainty associated with the estimate is not possible. Therefore this study proposes a multivariate probabilistic approach for estimation of CEC and SSA. First, a five-dimensional database (278×5) for parameters liquid limit (LL), plasticity index (PI), clay fraction (CF), CEC and SSA (labelled as CLAY/C-S/5/278) is developed. Thereafter, multivariate distribution for the five parameters in the database is constructed using vine copula approach. Implementation of the proposed approach is demonstrated by updating prior/unconditional probability density function (PDFs) of CEC and SSA given single/ multiple clay parameters using Bayes’ rule. The posterior/conditional PDFs of CEC and SSA are also summarized as practitioner friendly analytical expressions. Two geotechnical application examples are also shown. In the proposed approach, CEC and SSA are characterized by their complete joint distribution, and is, therefore, superior to the popular deterministic transformation approach in literature.

scholarly journals Effect of moisture content on some physical properties of Canarium schweinfurthii Engl. fruits

2016 ◽  
Vol 62 (No. 4) ◽  
pp. 162-169 ◽  
Author(s):  
J.C. Ehiem ◽  
V.I.O. Ndirika ◽  
U.N. Onwuka
Keyword(s):  
Moisture Content ◽  
Physical Properties ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Geometric Mean ◽  
Physical Parameters ◽  
True Density ◽  
Effect Of Moisture ◽  
Mass Volume

The effect of moisture content on some physical properties of three varieties of Canarium schweinfurthii Engl. fruits (small, large and long) was studied at 40.91%, 34.92%, 23.44%, 18.5% and 11.03% moisture content on wet basis in order to solve problems associated with designing and development of processing and handling equipment for these fruits. The physical parameters investigated were major, intermediate, minor diameters, geometric mean diameter, unit mass, volume, sphericity, density, bulk density, roundness, aspect ratio, porosity, surface and specific surface area. The results obtained showed that the physical parameters decreased linearly with a decrease in moisture content. Major diameter and true density of all the fruit varieties were not affected significantly (P < 0.05) by moisture content. Canarium schwein-furthii Engl. fruits are not round but spherical and oblong, hence, they can rather roll than slide. Among the studied varieties, small Canarium schweinfurthii Engl. is less bulky, has the highest specific surface area and is more porous.

Sign in / Sign up

Export Citation Format

Share Document