Some factors affecting compacted clay swelling

1970 ◽  
Vol 7 (1) ◽  
pp. 79-91 ◽  
Author(s):  
A. Yevnin ◽  
D. Zaslavsky
Keyword(s):  
Moisture Content ◽  
Volume Change ◽  
Empirical Equation ◽  
Clay Soil ◽  
Initial Density ◽  
Initial Moisture Content ◽  
Swelling Pressure ◽  
Compacted Clay ◽  
Factors Affecting ◽  
Applied Loading

Volume change after saturation was determined on specimens of a statically compacted clay soil. It was found that density after swelling increases linearly with increasing initial density, initial moisture content, and increasing logarithm of applied loading pressure. An empirical equation with five coefficients and a constant, found with the aid of a computer, represents the results with a coefficient of correlation close to 1. An equation for the swelling pressure was also obtained from this equation. Results of specimens which consolidated did not fit the lines obtained for swelling. The relationships obtained were explained by the influence of particle reorientation and moisture content on swelling tendency.

scholarly journals Effects of Torefaction with Counter-Flow Multi Baffle (COMB) Reactor and Electric Furnace on the Properties of Jabon (Anthocephalus cadamba) Pellets

2020 ◽  
Vol 8 (1) ◽  
pp. 65
Author(s):  
Yogi Sulistio ◽  
Indra Gumay Febryano ◽  
Jiho Yoo ◽  
Sangdo Kim ◽  
Sihyun Lee ◽  
...  
Keyword(s):  
Moisture Content ◽  
Residence Time ◽  
Electric Furnace ◽  
Color Change ◽  
Research Result ◽  
Initial Density ◽  
Initial Moisture Content ◽  
Wood Pellets ◽  
Counter Flow ◽  
Anthocephalus Cadamba

The objective of this study was to improve the quality of jabon (Anthocephalus cadamba) wood pellets through torrefaction with Counter-Flow Multi-Baffle (COMB) reactor and electric furnace (EF). COMB is a reactor that can conduct torrefaction with a short residence time, approximately around 3 to 5 min. The torrefaction with COMB reactor was conducted at 260°C and 280°C C, with a residence time of 3 min. The torrefaction with EF used the temperature of 260°C and 280°C with a duration of 20 min. The pellet properties evaluated include the color changes, physical characteristics, and heating values. The result showed that the color of Jabon wood pellet was totally changed after torrefaction with COMB reactor reaching the highest overall color-change (∆E *) of 21,9 in the long pellets and 21,7 in the short pellets, while torrefaction with EF resulted in the highest ∆E* of 28,6 and 23,2, in the long and short pellets, respectively. The initial moisture content of the long and short pellets of Jabon wood were 12,41% and 12,33%. After torrefaction with COMB the moisture content decreased to 2,85% and 2,61%, while after torrefaction with EF the values decreased to 2,77% and 2,58%. The initial density of the long and short pellets were 1,05 g/cm3 and 0,97 g/cm3. The density decreased to 0,91 g/cm3 and 0,76 g/cm3 after torrefaction with COMB reactor, and decreased to 0,87 g/cm3 and 0,75 g/cm3 after torrefaction with EF. The research result also showed that the initial heating value of long and short pellets of 17,69 MJ/kg increased to 31,79 MJ/kg (long pellets) and 32.02 MJ/kg (short pellets) after torrefaction with COMB reactor, and increased to 19.74 MJ/kg (long pellets) and 19.99 MJ/kg (short pellets) after torrefaction with EF. Torrefaction with COMB reactor with shorter residence time resulted in a higher improvement in bioenergetic properties of jabon wood pellets in comparison to torrefaction with EF.Keywords: Anthocephalus cadamba, Counter-Flow Multi Baffle, torrefaction

scholarly journals Characterization of the High Swelling Green Clay in the Vicinity of Amman Area

2021 ◽  
Vol 15 (1) ◽  
pp. 360-369
Author(s):  
Monther Abdel Hadi ◽  
Ibrahim Khliefat ◽  
Nafeth Abdelhadi ◽  
Nidhal Saada
Keyword(s):  
Moisture Content ◽  
Clay Mineral ◽  
Initial Moisture Content ◽  
Swelling Pressure ◽  
Liquid Limit ◽  
Engineering Properties ◽  
Dry Density ◽  
Initial Water Content ◽  
Foundation Design ◽  
Green Clay

Introduction: Jordan is awarded huge areas in the north and western part of the country in which brown and green clay is dominant. This research focuses on the problems and behaviour of the green clay only. The main problem of the green clay is its high swelling pressure which is the main cause of excessive settlement and wall cracks in buildings, especially during the wet season. Methods: This study aims to investigate the engineering properties and behaviour of the green clay deposits in the Amman area, which will serve as a guide for both geotechnical and structural engineers when preparing the foundation design. Results: Based on the consolidation test, the investigated green clay showed high swelling pressure of 3.11 kg/cm2, liquid limit (LL) of 73%, plasticity index (PI) of 40%, the shrinkage limit (SL) of 12%, and liquidity index (LI) of 0.125. The moisture content at saturation is 35.14%, while the natural moisture content is 28%, dry density is 1407 kg/m3, cohesion (C) is 0.20 kg/cm2 and unconfined compressive strength is 1.05 kg/cm2. The XRD results of the clay size fraction have confirmed the presence of the expansive clay mineral smectite as the essential clay mineral together with kaolinite. Results provide a general understanding of the behaviour and properties of the green clay, and the regression analysis showed good correlations between the liquid limit and initial moisture content with the compression index and also between the initial void ratios with the swelling index. Conclusion: Changes in the volume are due to the unsaturation level of clay when provided with initial water content.

scholarly journals Effect of Plastic Film Residue on Vertical Infiltration Under Different Initial Soil Moisture Contents and Dry Bulk Densities

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1346
Author(s):  
Junhao Cao ◽  
Pengpeng Chen ◽  
Yupeng Li ◽  
Heng Fang ◽  
Xiaobo Gu ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Water ◽  
Initial Moisture Content ◽  
Comprehensive Treatment ◽  
Burial Depth ◽  
Plastic Film ◽  
Wetting Front ◽  
Factors Affecting ◽  
Pollution Area

In arid and semi-arid regions, plastic film mulching can effectively improve crop yield, but with the increase of service life, a lot of residual plastic film (RPF) remains in the soil. The application of a RPF to a soil will alter soil moisture processes, and thus, affect the soil water distribution and its effectiveness. A quadratic regression orthogonal design was used to study the effects of initial moisture content (IMC), dry bulk density (DBD), residual plastic film content (RPFC), and the burial depth of RPF on the migration time of wetting front (MF), moisture content (MC), and accumulative infiltration (AI) of a test soil. It was found that IMC, DBD, and RPFC were the main factors affecting MC, MF, and AI, while the burial depth of RPF had no significant influence. The order of influence for the factors affecting MF was IMC > DBD > RPFC, while the order of influence for the factors affecting MC and AI was DBD > IMC > RPFC. RPFC was parabolic in relation to MF, MC, and AI, when it was in the range of 50–100 kg/hm2, while within the same range MC and AI reached a maximum and MF reached a minimum. The analysis of the interactive responses revealed that when the DBD was greater than 1.29g/cm3, the MF initially decreased and then increased with the increase of RPFC. When the RPFC was more than 100 kg/hm2, the MF initially increased and then decreased with the increase of the DBD. When the DBD was larger than 1.31 g/cm3, the AI initially increased and then decreased with the increase of RPFC. It was apparent that the RPF not only had a blocking effect on the wetting front, but also affected the water flow. When the RPFC was between 50 and 100 kg/hm2, the soil MC was significantly increased. It was suggested that the RPF pollution area should increase the mechanical recovery of plastic film, standardize the use and recycling of agricultural RPF, optimize the planting model, and establish a recyclable model for the treatment of RPF pollution, and it was proposed that the RPFC remaining after recovery of the RPF should be less than 50 kg/hm2.This study can prove the law of soil water movement in the residue film pollution area and provide reference and solution ideas for the comprehensive treatment of residue film pollution in farmland.

ALTERATIONS OF SOIL STRUCTURE UPON FREEZING AND THAWING AND SUBSEQUENT DRYING

1968 ◽  
Vol 48 (2) ◽  
pp. 193-197 ◽  
Author(s):  
W. C. Hinman ◽  
Frederick Bisal
Keyword(s):  
Moisture Content ◽  
Soil Structure ◽  
Room Temperature ◽  
Clay Soil ◽  
Soil Aggregates ◽  
Initial Moisture Content ◽  
Aggregate Size ◽  
Freezing And Thawing ◽  
Initial Size ◽  
Freeze Dried

A laboratory investigation of a clay soil indicated that the percentage of aggregates < 1 mm in diameter might be increased, decreased or unaffected by freezing and thawing depending on the initial moisture content, the initial size of soil aggregates and the method of drying the sample. Little or no changes in aggregate size occurred if the initial moisture content was at 15 atmospheres. At 0.1 atm, aggregates which were initially coarse (> 4 mm) tended to break down slightly when exposed to alternate freezing and thawing followed by air-drying at room temperature. On the other hand, a substantial decrease in aggregates < 1 mm in diameter occurred when aggregates which were originally fine received the same sequence of treatments. However, if the samples were freeze-dried following the same treatments, all aggregates were reduced to < 1 mm in diameter. Similar trends were established with samples which were continuously frozen and when the initial moisture content was at 0.33 atm, although the magnitude of the change was much smaller. It is proposed that forces engendered during freezing disrupt aggregates, but this process is reversed during thawing and drying at room temperatures.

VOLUME CHANGE OF COMPACTED CLAY SOIL AGGREGATES

Soil Science ◽  
1968 ◽  
Vol 105 (2) ◽  
pp. 106-111 ◽  
Author(s):  
R. K. CHANG ◽  
B. P. WARKENTIN
Keyword(s):  
Volume Change ◽  
Clay Soil ◽  
Soil Aggregates ◽  
Compacted Clay

scholarly journals Factors Affecting the Swelling-Compression Characteristics of Clays in Yichang, China

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Changxi Huang ◽  
Xinghua Wang ◽  
Hao Zhou ◽  
Yan Liang
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Expansive Soil ◽  
Swelling Pressure ◽  
Stress Path ◽  
Dry Density ◽  
Initial Water Content ◽  
Initial Water ◽  
Swelling Properties ◽  
Vertical Loading

Expansive soil has been studied for eighty decades because it is prone to cause geotechnical engineering accidents. The results of the moisture content effects on the expansive pressure were not consistent in the literatures. In this paper, swelling deformation and pressure tests were conducted to clarify the effects of the initial water content on the swelling properties. The relation of expansive stress and initial moisture content was accurately described with a Gaussian distribution, unlike in the previously published studies. These results could be explained by the change in the microstructure with diverse moisture contents. In addition, dry density and vertical stress influences on expansive properties were analysed. With an increase in the vertical loading, the soil samples first expanded, and then the samples with a lower dry density collapsed; however, the samples with a higher dry density did not collapse, even under a considerable vertical loading. Furthermore, the relation between stress path and expansive pressure was examined. It was observed that the swelling pressures obtained from the constant volume tests were greater than the results from the swell under load tests. The relationship between the swelling pressure and swelling strain was also analysed.

scholarly journals Time rate of swelling of compacted highly plastic clay soil from Sudan

2018 ◽  
Vol 149 ◽  
pp. 02032 ◽  
Author(s):  
A M Elsharief ◽  
Mai Sufian
Keyword(s):  
Moisture Content ◽  
Clay Soil ◽  
Initial Moisture Content ◽  
Hyperbolic Model ◽  
Dry Density ◽  
Expansive Clay ◽  
Time Intervals ◽  
One Dimensional ◽  
Swell Percent ◽  
Three Stages

This paper investigates the development of swelling with time for a highly plastic and potentially expansive clay from Sudan. Soil samples were prepared in the laboratory at different moisture content values. The prepared samples were placed in the oedometer ring at three density levels and then placed in an oedometer cell which allows one dimensional swelling. Swelling was observed at different time intervals to 48 hours. The data was analyzed to determine the development of swelling with time. The data analysis clearly demonstrated three stages of swelling, initial, preliminary and secondary for all tested samples except the quasi-saturated ones. The swell percent and primary swelling were very sensitive to the initial moisture content and dry density of the tested samples. Most of the swelling took place during the first 24 hours for all the tested specimens. The hyperbolic model was assessed for prediction of the percent swell. The 12 hours data was found to be very successful in predicting the percentage swell.

Analysis of the Factors Affecting the Value-Added to Dried Pineapple Fruits Using a Simple Interactive Computer Model

2011 ◽  
Vol 4 ◽  
pp. 1-14
Author(s):  
Samwel Victor Manyele
Keyword(s):  
Moisture Content ◽  
Loss Rate ◽  
Initial Moisture Content ◽  
Value Added ◽  
The Other ◽  
Raw Material ◽  
Factors Affecting ◽  
Dried Fruits ◽  
Percent Increase ◽  
Major Factors

In this work, the effect of peel and reject losses on the value added to the dried pineapple fruits was analyzed. The major factors include final moisture content, Xwf; peel loss rate, Rp; reject loss rate, Rrj; and the reject-to-peel ratio, Rrj/Rp. The value added was expressed as the percent increase in value (PVA) which is an indication of price of dried fruits. Material losses were expressed as percent raw material lost (PRML), and total raw material lost per kg of raw material. The PVA decreases with increasing Xwf for all levels of initial moisture content. The PVA increases faster for Rp > 0.1 kg/kg from 67% to 90%. The PVA decreased with increasing Rrj/Rp. The PRML, on the other hand, increased faster with Rp for Rp > 0.1 kg/kg. However, PRML decreased faster as Rrj/Rp was increased. The total losses decreased with increasing Rrj/Rp and also with increasing Rrj.

scholarly journals Utilization of dolerite waste powder for improving geotechnical parameters of compacted clay soil

2021 ◽  
Vol 13 (1) ◽  
pp. 1523-1535
Author(s):  
Syed Husnain Ali Shah ◽  
Mohammad Arif ◽  
Qasim ur Rehman ◽  
Fawaz Manzoor
Keyword(s):  
Compressive Strength ◽  
Moisture Content ◽  
Unconfined Compressive Strength ◽  
Void Ratio ◽  
Clay Soil ◽  
Atterberg Limits ◽  
Degree Of Saturation ◽  
Dry Density ◽  
Compacted Clay ◽  
Grain Sizes

Abstract This study explores how dolerite cutting waste could be utilized for improving the quality of compacted clay soils. Different proportions of dolerite waste powder with varying grain sizes were used as admixtures and their impact on clay soil properties investigated. Ten samples were prepared by mixing clay soil with different proportions of dolerite waste powder having grain sizes of 0.210, 0.297, and 0.420 mm. The resulting samples were subjected to Proctor compaction, and their maximum dry density and optimum moisture content were measured. Next, all the compacted samples were subjected to geotechnical testing, including the determination of Atterberg limits, California bearing ratio (CBR), unconfined compressive strength, and specific gravity (Gs). The values of compaction parameters, Atterberg limits, and Gs were utilized for finding the porosity, void ratio, saturation potential, liquidity index (LI), and consistency index (CI). The results demonstrate that the addition of dolerite powder produces a substantial improvement in the plasticity index, compaction parameters, CBR, unconfined compressive strength, Gs, porosity, void ratio, degree of saturation, LI, and CI. The foremost reason for this improvement is the presence of denser and less water-adoring minerals in the added dolerite relative to pristine clay soil. Furthermore, the observed positive impact on the soils’ geotechnical comportment is comparatively higher with coarser than finer dolerite because of the decrease in surface area that causes a reduction in the moisture content and porosity but an increase in the density of soil.

Examination of Tobacco Hygroscopicity / Über die Hygroskopizität des Tabaks

1965 ◽  
Vol 3 (1) ◽  
Author(s):  
L. Hübschen
Keyword(s):  
Moisture Content ◽  
Sorption Isotherm ◽  
Initial Moisture Content

AbstractThe present paper shows the detectable factors on which a sorption isotherm depends. Even if it is well-known that a sorption isotherm is most essentially conditioned by influences of the respective tobacco variety, other factors, such as temperature, initial moisture content, or fibre dimension, play a part as well. In general, a sorption isotherm constitutes a ''summation'' of such factors and, in the end, a combination of desorption and adsorption if the tobacco is dried or moistened from the average commercial moisture content. The tobacco hysteresis is experimentally investigated and discussed

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