COMPACTION OF LINEAR ELASTIC-CREEPING INHOMOGENEOUS SOILS

2021 ◽  
pp. 45-50
Author(s):  
А. Дасибеков ◽  
Ж. Т. Айменов ◽  
Б. Арапов ◽  
Д. С. Мырзалиев
Keyword(s):  
Solid Particles ◽  
Independent Variables ◽  
Linear Elastic ◽  
Compressive Stresses ◽  
Porosity Coefficient ◽  
Soil Skeleton ◽  
Soil Compression ◽  
Straight Lines

В данной работе рассмотрен процесс уплотнения линейных упругоползучих неоднородных грунтов. Областью изменения независимых переменных является прямоугольник, образованный прямыми х=±ℓ; y=0; y=h. Уплотнение этого прямоугольника безусловно определяется своей сжимаемостью. Сжимаемость основания зависит как от типа грунта, так и от характера нагрузки. При этом деформация сжатия грунтов в основном происходит вследствие сближения твердых частиц между собой и оценивается изменением коэффициента пористости при изменении сжимающих напряжений в скелете грунта. Определение этой зависимости обычно производится лабораторным путем в компрессионных приборах. In this paper, the process of compaction of linear elastic-creeping inhomogeneous soils is considered. The domain of change of independent variables is a rectangle formed by straight lines x = ±l; y = 0; y = h. the Compaction of this rectangle is unconditionally determined by its compressibility. Compressibility of the base depends on both the type of soil and the nature of the load. In this case, the deformation of soil compression mainly occurs due to the convergence of solid particles with each other and is estimated by changing the porosity coefficient when compressive stresses in the soil skeleton change. The determination of this dependence is usually made by laboratory means in compression devices.

scholarly journals Determination of macro-scale soil properties from pore-scale structures: model derivation

2018 ◽  
Vol 474 (2209) ◽  
pp. 20170141 ◽  
Author(s):  
K. R. Daly ◽  
T. Roose
Keyword(s):  
Pore Space ◽  
Solid Particles ◽  
Underlying Structure ◽  
Pore Scale ◽  
Homogenization Procedure ◽  
Macro Scale ◽  
Model Derivation ◽  
Scale Structures ◽  
Homogenization Scheme

In this paper, we use homogenization to derive a set of macro-scale poro-elastic equations for soils composed of rigid solid particles, air-filled pore space and a poro-elastic mixed phase. We consider the derivation in the limit of large deformation and show that by solving representative problems on the micro-scale we can parametrize the macro-scale equations. To validate the homogenization procedure, we compare the predictions of the homogenized equations with those of the full equations for a range of different geometries and material properties. We show that the results differ by ≲ 2 % for all cases considered. The success of the homogenization scheme means that it can be used to determine the macro-scale poro-elastic properties of soils from the underlying structure. Hence, it will prove a valuable tool in both characterization and optimization.

A Comparative Analysis of the Power of Selected European Countries. The Economic Determinants

2021 ◽  
Vol 37 (37) ◽  
pp. 22-42
Author(s):  
Alicja Paluch ◽  
Henryk Spustek
Keyword(s):  
Czech Republic ◽  
Comparative Analysis ◽  
European Countries ◽  
Economic Power ◽  
Strongly Correlated ◽  
The Czech Republic ◽  
Independent Variables ◽  
Economic Sphere ◽  
National Power

The ever-increasing need for in-depth analysis and quantification of the national power, in particular ‘hard’ and ‘soft’ power-generating factors as well as difficulties in identifying a comprehensive and effective method for scientific determination of the national power, have given rise to research in the indicated scientific issues within this article. The presented considerations aim to define the assumptions for a descriptive sub-model that would enable a comparison of Poland’s power in the economic sphere (which is a component of the non-military sphere) with the power of selected European countries. The research hypothesis is that, among the variety of descriptive variables in the economic sphere of the national power, there is a subset of mutually independent variables, at the same time strongly correlated with the national power, which make it possible to define assumptions for the sub-model of the national power. The steps of the research procedure were carried out using the method of system analysis (multi-criteria comparative analysis) and statistical analysis. The research activities undertaken have shown that the factors that are strongly correlated with the national power in the economic area of the European countries adopted for the analysis are: dynamics of industrial production, private sector credit flows and economic freedom index. The comparative analysis carried out demonstrates that the greatest increase in the economic power in the analysed period took place in Germany (0.68). Slightly smaller growth was recorded in the Czech Republic (0.62) and Poland (0.60), while the lowest value of increase was in Romania (0.23). The conducted qualitative comparative analysis of the economic power of selected European countries allowed to conclude that the independent variables identified are crucial for the formation of the economic power of the analysed countries. At the same time, a fairly strong position of the Czech Republic and Poland in relation to the economic power of Germany was found. The performed quantification of the economic power of the European countries provides a basis for the correct determination of changes in the power distribution of political units, assessment of the power and resources held by the state.

Experimental Determination of Statistical Properties of Two-Phase Turbulent Motion

1960 ◽  
Vol 82 (3) ◽  
pp. 609-621 ◽  
Author(s):  
S. L. Soo ◽  
H. K. Ihrig ◽  
A. F. El Kouh
Keyword(s):  
Gas Phase ◽  
Tracer Diffusion ◽  
Statistical Properties ◽  
Solid Particles ◽  
Turbulent Motion ◽  
Two Phase ◽  
Gaseous State ◽  
Diffusion Technique ◽  
And Diffusion

Experimental methods for the determination of certain statistical properties of turbulent conveyance and diffusion of solid particles in a gaseous state are presented. Methods include a tracer-diffusion technique for the determination of gas-phase turbulent motion and a photo-optical technique for the determination of motion of solid particles. Results are discussed and compared with previous analytical results.

scholarly journals DETERMINATION OF PRODUCTION WELL'S COLLECTORS POROSITY IN SOUTH-GEOLOGICAL AREA

2016 ◽  
pp. 25-29
Author(s):  
G. E. Stroyanetskaya
Keyword(s):  
Electrical Resistivity ◽  
Geophysical Methods ◽  
Caliper Measurement ◽  
Porosity Coefficient

The problems of collectors at the stage of calculating the reserves in operating incline directional wells, penetrated on clay, polymer-clay solution, polymer washing liquid with hydrochloric-calcium foundation were considered. The electrical resistivity of the solution and the washing liquid from 0.1 to 1 O·mm. According to geophysical methods, establishing of the criteria for the allocation of the collectors requires coring. The main methods for the isolation of collectors are lateral, microlaterolog survey and caliper measurement. The techniques of the gas-saturated collectors porosity coefficient determination were considered.

scholarly journals DETERMINATION OF THE REAL VALUES OF KINEMATIC INDEX CORRESPONDING TO THE MECHANICAL SEPARATION PROCESS

2017 ◽  
Vol 22 (2) ◽  
Author(s):  
EMILIAN MOȘNEGUȚU ◽  
VALENTIN NEDEFF ◽  
MIRELA PANAINTE-LEHĂDUȘ ◽  
NARCIS BÂRSAN ◽  
DANA CHIȚIMUȘ ◽  
...  
Keyword(s):  
Separation Process ◽  
Experimental Batch ◽  
Solid Particles ◽  
Common Method ◽  
The Real ◽  
Mechanical Separation

This article presents the methodology for determining the real values of kinematic indices which characterizes the mechanical separation of a mixture of solid particles. Mechanical separation of a mixture of solid-solid on surface provided with holes is the most common method of separation. To optimize equipment that performs this operation, both theoretical and practical characteristics are determined. Kinematic indices are part of the theoretical characteristics, helping to identify behavior of solid particles on a surface flat swing. Starting from an experimental batch, real values of the kinematic indices corresponding to up, down and sideways movement on the sieve were determined for the following types of real particles: grain, large grain beans, small grain beans and soybeans.

APPROXIMATING THE POTASSIUM FERTILIZATION REQUIREMENT OF COTTON ON SOME REPRESENTATIVE SEMIARID TROPICAL SAVANNAH SOILS OF NIGERIA

1981 ◽  
Vol 61 (3) ◽  
pp. 507-516
Author(s):  
GANYIR LOMBIN
Keyword(s):  
Cotton Yield ◽  
Seed Cotton ◽  
Potassium Fertilizer ◽  
Quadratic Polynomials ◽  
Independent Variables ◽  
Regression Procedure ◽  
Fertilizer Requirement ◽  
Relevant Variables ◽  
Multiple Determination

Potassium fertilizer requirement of rain-fed cotton was evaluated in a 3-yr field study conducted at three locations using four rates (0, 25, 50 and 75 kg∙ha−1)of K. Significant response was not obtained above 25 kg∙ha−1 applied K. Quadratic polynomials, using leaf K, exch. K, exch. (Ca + Mg)/K and applied K as independent variables, were fitted to the seed-cotton yield. As a single parameter, leaf K emerged the best predictor of yield with a coefficient of multiple determination (R2) of 86% and a corresponding regression equation of: Y (yield) = 3099.2 + 6031.6%K − 1643.3 (%K)2, followed by fertilizer K with a coefficient of multiple determination of 81% and a yield equation of: Y = 1302.3 + 53.96 app. K − 0.54 (app. K)2. Soil exch. K and (Ca + Mg)/K ratio were slightly less efficient in predicting yield giving R2 values of 0.62 and 0.76, respectively, when both the linear and quadratic terms were entered into their respective yield equations. When all the 12 possible entries (linear, and second-order terms and their square root transformations) were fed into the computer and regressed over cotton yield using a step-wise regression procedure, only two variables, leaf %K and (Ca + Mg)/K, significantly fitted the yield equation giving a predictive value of 87%. But the improvement in the precision of yield predictability as measured by the R2 value was only marginal and would not justify recommending the equation considering the extra laboratory work that will be needed to obtain the relevant variables. Critical values of 1.84% in index leaf, 0.19 meq/100 g exch. K and 50 kg∙ha−1 applied K were approximated for a maximum predicted yield range of 2440–2700 kg∙ha−1.

Light Transmission Model for Determination of the Refractive Index of Solid Particles in Suspensions: An Immersion Study

2011 ◽  
Vol 65 (5) ◽  
pp. 557-560 ◽  
Author(s):  
Jukka Räty ◽  
Ilpo Niskanen ◽  
Risto Myllylä ◽  
Kai-Erik Peiponen
Keyword(s):  
Refractive Index ◽  
Light Transmission ◽  
Solid Particles ◽  
Transmission Model

Determination of number of independent variables in kinetic systems

1977 ◽  
Vol 67 (11) ◽  
pp. 5401-5402
Author(s):  
Igor W. Plesner ◽  
Yi‐der Chen
Keyword(s):  
Independent Variables

Evaluation of Residual Stresses in PVD Coatings by Means of Strip Substrate Length Variation and Curvature Method of Plate Substrate

2017 ◽  
Vol 267 ◽  
pp. 212-218 ◽  
Author(s):  
Harri Lille ◽  
Alexander Ryabchikov ◽  
Jakub Kõo ◽  
Eron Adoberg ◽  
Liina Lind ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Length Change ◽  
Steel Plates ◽  
Length Variation ◽  
Pvd Coatings ◽  
Compressive Stresses ◽  
Steel Strips ◽  
Middle Cross Section ◽  
Method Strip

The aim of the study was to determine macroscopic residual stresses in Physical Vapor Deposits (PVD) coatings through measurement of the length variation of the strip substrates coated on both sides. The length change of the strip was reduced to the deflection of the middle cross-section of the elastic element and was recorded by four strain gauges. For validating the obtained results, the conventional curvature method was used. As an application, residual stresses in hard AlCrN PVD coatings were investigated. The coatings were nanolayered to achieve better coating toughness for blanking and punching applications. The steel strips and steel plates with two thicknesses were used as the substrate. The values of the compressive residual stresses, determined by both methods for the investigated coatings, were very high (3.3 -3.6 GPa) independent of coating thickness and practically equal within the measurement uncertainty of the method. Good agreement between the experimental results obtained with both methods suggests that the presented method, strip length variation, is applicable for determination of residual stresses in coatings. Compressive stresses in coatings are desirable as they strengthen the coating.

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