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Description of the shrinkage characteristic in alluvial clay soils

100%

Szatylowicz J., Brandyk T., Hewelke P., Gnatowski T.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1996

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tom 436

The paper presents the results of measurements of shrinkage characteristic for alluvial clay soils from the Delta of Vistula River. Measurements were conducted on undisturbed soil aggregates using ‘so-called’ saran resin method. Five following shrinkage characteristic models were fitted to measured data: four segment analytical model, combined exponential-linear model, general soil volume changes equation, three straight lines model and logistic model. The comparison of different models depending on coordinate system as well as advantages and disadvantages of various models are discussed.

2

Estimation of the density of the clay-organic complex in soil

86%

Czyz E. A., Dexter A. R.

International Agrophysics

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2016

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tom 30

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nr 1

3

Functioning of systematic draining within clay soils in central Poland

86%

Wanke A.

Annals of Warsaw Agricultural University. Land Reclamation

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2000

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tom 30

99-107

4

Shear strength of clayey soils from the vicinity of Gorlice and Ciężkowice

86%

Zydron T., Prawica E.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2015

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tom 47

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nr 3

The work presents results of maximum and residual strength tests of six clayey soils from the landslide areas near Gorlice and Ciężkowice. The tests were carried out in a direct shear apparatus on samples of dimensions 60 × 60 mm that were sheared at least three times. A shearing strain rate was equal 0.1 mm·min–1, and the range of horizontal deformation of the samples was equal 20%. The results of the tests revealed that multiple shearing of the soil caused a signifi cant decrease of its shear strength, resulting in signifi cant changes in cohesion, and the smaller changes in the angle of internal friction. It was shown that the threetime shearing reduced the initial shear strength of about 50%, and further three series of shearing decreased it approximately 15% more. The study also showed that by using a Coulomb-Mohr shear strength linear equation, the analyzed soils had a little residual cohesion. Therefore, to describe the characteristics of the residual strength, there were used two non-linear equations proposed by Mesri and Shanien (2003) and Lade (2010), which led to the same results. It was also shown that the use of non-linear characteristics of the residual strength at low values of the normal stresses gave more unfavourable results of stability calculations in relation to the method based on the linear strength characteristic taking into consideration the presence of the residual cohesion.

5

Assessment of permeability and pore water pressure in Warsaw clays based on in situ measurements

86%

Skutnik Z.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2011

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tom 43

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nr 2

6

Crack tortuosity in swelling clay soils

86%

Chertkov V. Y., Ravina I.

International Agrophysics

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1999

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tom 13

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nr 1

7

Effect of reclamation on the structure of silty-clay soils irrigated with saline-sodic waters

72%

Cucci G., Lacolla G., Pagliai M., Vignozzi N.

International Agrophysics

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2015

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tom 29

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nr 1

The objective of the work was to evaluate, by using the micromorphometric method, the effects of reclamation on porosity of two different clay loam soils irrigated with saline-sodic waters. Soil samples of the Ap horizon were put in cylindrical containers and irrigated with 9 types of saline-sodic waters (3 levels of salinity combined with 3 levels of sodicity). After a 4-year period, correction treatments were initiated by addition of calcium sulphate and leaching until electrical conductivity and sodium absorption ratio values of the drainage water matched 3 dS m-1 and 9, respectively. After 2 years of correction treatments, undisturbed soil samples were taken from the surface layer and soil thin sections for porosity measurements. Both soils did not show critical macroporosity values (> 10%, below this threshold a soil is classified as compact). Nevertheless, the soils exhibiteda different behaviour: total porosity of the Pachic Haploxeroll soil was not affected by difference in water salinity and alkalinity; on the contrary, the Udertic Ustochrept soil showed a lower porosity associated with higher salt concentration in the irrigation waters. This may be due to the different iron and aluminium sesquioxides content and, as a consequence, a different effect on soil aggregate stability.

8

The analysis of changes of water stores in clay soil on the background of weather conditions in Puczniew area

72%

Baryla A., Ptach W.

Infrastruktura i Ekologia Terenów Wiejskich

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2013

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nr 1/III

This paper examines the changes in stocks of water in clay soils against precipitation and changes in the groundwater table. The study was conducted during the summer period (May-September) in 2001 and 2002. According to the Kaczorowska` s criteria (1962) the year 2001 was very wet, and the 2002 – average. In 2001, ground water table was at a depth of 0 to 190 cm below ground surface level, and in 2002, from 50 cm to 150 cm below the surface. Water storages in the root zone (0-35 cm) developed in 2001 at the level of 100 to 125 mm, in 2002, from 88 mm to 122 mm.

9

Determination of the Resilient modulus MR for the lime stabilized clay obtained from the repeated loading CBR tests

72%

Sas W., Gluchowski A., Szymanski A.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2012

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tom 44

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nr 2

The main aim of this paper is to prove that CBR repeated test is useful to give an adequate like unconfined cyclic triaxial test parameters for design the pavement and subgrade soils. That parameter is the Resilient modulus (MR) which is the elastic modulus based on the recoverable strain under repeated load. Resilient modulus (MR), is an important parameter which characterizes the subgrade’s ability to withstand repetitive stresses under traffic loadings. The 1993 AASHTO guide for design of flexible pavements recommends the use of MR. The additional aim is connected with the concept of sustainable development. For many countries, where resources are at premium, it is very important that stabilized local soil can be used for road construction. For ensuring that stabilized clay can be used for pavement material standard compaction, CBR and repeated CBR tests were performed. In that paper parameter MR of the subgrade lime stabilized clay soil by laboratory CBR repeated test were determined using for calculation formulas from triaxial cyclic test. Based on AASHTO empirical equation the static CBR values using back analysis was also calculated. Finally both values of CBR determined and calculated were compared.

10

Crack width, cross-section area, and volume in swelling clay soils

72%

Chertkov V. Y., Ravina I.

International Agrophysics

|

1999

|

tom 13

|

nr 2

11

Workability of heavy soils in a temperate climate

72%

Muller L., Schindler U., Rogasik H.

Bibliotheca Fragmenta Agronomica

|

1997

|

tom 2B

12

Soil compaction control with a light, unmanned tractor in two tillage system

72%

Alakukku L., Poyhonen A., Sampo M.

Bibliotheca Fragmenta Agronomica

|

1997

|

tom 2A

13

The impact of soil physical and mechanical properties on draft resistance of ploughs

58%

Vilde A., Rucins A.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

|

2004

|

tom 04

14

Russula medullata (Russulales, Basidiomycota): a new species in the mycobiota of Poland

58%

Mleczko P., Kozak M., Zubek S.

Polish Botanical Journal

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2010

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tom 55

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nr 2

15

The effects of 2,4-D and dicamba on isoproturon metabolism and selected biochemical parameters in clay soil

58%

Telesinski A.

Electronic Journal of Polish Agricultural Universities. Series Environmental Development

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2010

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tom 13

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nr 1

16

Aggregate water stability of sandy and clayey loam soils differently compacted with and without wheat plants

58%

Balashov E., Bazzoffi P.

International Agrophysics

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2003

|

tom 17

|

nr 4

17

Chosen properties of clayey soils on an afforested dumping ground of a sulfur mine

44%

Bielinska E. J., Domzal H., Wegorek T.

Acta Agrophysica

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2001

|

tom 56

Ograniczanie wyników

Description of the shrinkage characteristic in alluvial clay soils

Estimation of the density of the clay-organic complex in soil

Functioning of systematic draining within clay soils in central Poland

Shear strength of clayey soils from the vicinity of Gorlice and Ciężkowice

Assessment of permeability and pore water pressure in Warsaw clays based on in situ measurements

Crack tortuosity in swelling clay soils

Effect of reclamation on the structure of silty-clay soils irrigated with saline-sodic waters

The analysis of changes of water stores in clay soil on the background of weather conditions in Puczniew area

Determination of the Resilient modulus MR for the lime stabilized clay obtained from the repeated loading CBR tests

Crack width, cross-section area, and volume in swelling clay soils

Workability of heavy soils in a temperate climate

Soil compaction control with a light, unmanned tractor in two tillage system

The impact of soil physical and mechanical properties on draft resistance of ploughs

Russula medullata (Russulales, Basidiomycota): a new species in the mycobiota of Poland

The effects of 2,4-D and dicamba on isoproturon metabolism and selected biochemical parameters in clay soil

Aggregate water stability of sandy and clayey loam soils differently compacted with and without wheat plants

Chosen properties of clayey soils on an afforested dumping ground of a sulfur mine