scholarly journals The application of vapour equilibrium technique to control suction to study the shrinkage and water retention of compacted Claystone-Bentonite mixtures

2022 ◽  
Vol 1212 (1) ◽  
pp. 012029
Author(s):  
Y F Arifin ◽  
M Arsyad ◽  
M Afdi ◽  
H Muslim
Keyword(s):  
Sodium Chloride ◽  
Water Retention ◽  
Initial Moisture Content ◽  
Soil Samples ◽  
Initial Water Content ◽  
Potassium Sulphate ◽  
Salt Solutions ◽  
Initial Water ◽  
Compacted Soils ◽  
Total Suction

Abstract Understanding soil shrinkage and retaining water is essential for learning more about the possibility of cracking of liner. Moreover, the factors that influence it are also important to know to improve the material tested as hazardous waste liners. The vapour equilibrium technique is widely used to control suction of compacted soils experiencing drying-wetting phenomena. It is considered to be inexpensive, simple, and has the ability to adequately control the suction applied to soil samples. This paper, therefore, describes its application in studying the shrinkage and water retention in compacted claystone-bentonite mixtures. This involved using five saturated salt solutions including potassium sulphate (K2SO4), potassium chloride (KCl), sodium chloride (NaCl), potassium carbonate (K2CO3), and magnesium chloride (MgCl2.6H2O). The sample was allowed to be in equilibrium with the relative humidity salt solution and a calliper was used to measure the dimensions every day up to when this was achieved. The results showed the bentonite in the mixture affects the amount of shrinkage and water retention while the sample’s initial moisture content was also found to be very influential on the magnitude of the primary and residual shrinkage. Moreover, the sample’s ability to hold water was almost the same without differentiating the initial water content at a total suction of more than 41084.91 kPa.

Determination of the tensile strength of unsaturated tailings using bending tests

2015 ◽  
Vol 52 (11) ◽  
pp. 1874-1885 ◽  
Author(s):  
Bibiana Narvaez ◽  
Michel Aubertin ◽  
Faustin Saleh-Mbemba
Keyword(s):  
Tensile Strength ◽  
Water Content ◽  
Water Retention ◽  
Water Retention Curve ◽  
Initial Water Content ◽  
Ambient Conditions ◽  
Initial Water ◽  
Bending Tests ◽  
Retention Curve ◽  
Apparent Cohesion

Bending tests were conducted on specimens of unsaturated tailings from three hard rock mines to evaluate their tensile strength. Saturated samples were prepared at an initial water content, w0, of 40% and then naturally dried under ambient conditions to pre-selected degrees of saturation, Sr, which can be related to the corresponding suction using the water retention curve. The basic interpretation of the bending tests results is based on an elastic–brittle behavior. The results show how the tensile strength, σt, of unsaturated tailings varies with water content, w (and Sr). The experimental data are also used to evaluate Young’s modulus in tension, Et, and to estimate the apparent cohesion, capp, as a function of Sr. Predictive equations are also applied to estimate the values of σt of unsaturated tailings using the water retention curve.

The Influence of Dehumidifying Condition on Expansive Soil Engineering Properties

2012 ◽  
Vol 594-597 ◽  
pp. 487-492
Author(s):  
Xiong Wei Li ◽  
Ai Jun Wang ◽  
Guo Zhong Dai
Keyword(s):  
Shear Strength ◽  
Relative Humidity ◽  
Water Content ◽  
Expansive Soil ◽  
Expansion Ratio ◽  
Soil Samples ◽  
Engineering Properties ◽  
Drying Rate ◽  
Initial Water Content ◽  
Initial Water

The expansive soil behaviour of expansive deformation and shear strength is deeply influenced by humidity condition. Different soil drying rate was set with constant temperature and different relative humidity. When saturated soil samples was dried to the different predetermined water content, the expansion ratio test with the upper load was made. It is shown that in the condition of high relative humidity, the expansion ratio is high. The smaller initial water content and upper load may lead to a larger swelling deformation. When soil samples with different initial water content was fully expanded, the consolidated direct shear tests were made. It is shown that the smaller drying rate leads to the greater shear strength after full expansion. What’s more, the upper load may improve the soil shear strength.

scholarly journals Initial Moisture Content of Corncobs Plays an Important Role in Maintaining its Quality during Storage

2018 ◽  
Vol 38 (2) ◽  
pp. 167
Author(s):  
Lince Mukkun ◽  
Herianus J.D. Lalel ◽  
Yuliana Tandirubak
Keyword(s):  
Moisture Content ◽  
Water Content ◽  
Insect Pests ◽  
Initial Moisture Content ◽  
High Water ◽  
High Water Content ◽  
Initial Water Content ◽  
Initial Water ◽  
Plant Materials ◽  
Randomized Design

Maize is one of the important staple foods for people in Timor, East Nusa Tenggara Province, Indonesia. Subsistent farmers store the maize for their own consumption until the next harvest season, for seed and feed.  However, high initial water content of the kernel due to improper drying prior storage initiate serious damage and losses during the maize storage.  High water content promotes the growth of fungi and insects, and increase respiration rate, resulting in rapid deterioration of maize. The purpose of this study was to determine the initial moisture content that might minimize damage and losses of maize in the farmers’ storage, and to study the effects of some plant materials that are used to smoke corns before storage. The experiment was initiated by sun-drying the harvested corncobs for 0, 2, 4, 6, 8, and 10 days (6 hours a day). This experiment was designed using Completely Randomized Design with 6 treatments and 3 replications. Dried corncobs were stored in the farmer’s storage for 4 months. The effects of maize kernels’ initial water content on the development of water content in kernels; the percentage of damaged kernels; and the species of pathogen and insects were investigated during storage with 2-week intervals.  The results demonstrated that drying the corncobs prior storage for 10 days, resulting in 12.96% of water content, significantly decreased the percentage of seed damage to 6.5%, as compared to without drying process which resulted  in 63%.  Aspergillus flavus, Fusarium sp., and Penicillium sp were found to be the main pathogen during storage.  There are no insect pests found during the storage. 

Prediction Study of Capillary Rise Height on Unsaturated Soil

2013 ◽  
Vol 860-863 ◽  
pp. 1260-1264 ◽  
Author(s):  
Nian Qin Wang ◽  
Qing Tao Wang ◽  
Xiao Ling Liu ◽  
Qi Pang
Keyword(s):  
Moisture Content ◽  
Unsaturated Soil ◽  
Vertical Section ◽  
Capillary Rise ◽  
Initial Moisture Content ◽  
Absorption Capacity ◽  
Initial Water Content ◽  
Initial Water ◽  
The Difference ◽  
Rise Height

Based on the understanding of diseases of building’s foundation and manmade slope caused by water capillary rise, this thesis carried out a large number of laboratory tests by selfdeveloped absorption permeameter for unsaturated soil, in order to explore the capillary transport law of unsaturated soil. The thesis obtains some valuable results and conclusions: The moisture content shows minishing trend as the seepage fronts increasing, and reflects the gravitational potential of normal relations with the capillary action; (2) the water seepage frontal Hω% relation curve has no obvious inflection point, but the initial water content has an certain influence on the capillary moisture content distribution, the moisture content uses the initial moisture content of 12.5%, 9.8%, 8.0% and5.3% for testing showed an increasing trend at 4 cm and 16 cm sections, and the moisture content at the same section increased with the initial moisture content increasing, this reflects the rule that the smaller the moisture content is, the greater the matric potential, the water absorption capacity becomes stronger. (3)The moisture content difference between 4 cm and 16 cm of the initial moisture content is 12.5%, 9.8%, 8.0% and 9.8% is 1.48 %, 1.5 %, 1.7 % and 2.2 %, indicating that the smaller the initial moisture content is, the difference at the vertical section is greater. Finally, based on the relationship of Hω% curve, the thesis establishes the grey correlation prediction model, and forecasts the maximum capillary height of Lishi loess is 182cm.

scholarly journals Responses of Soil Infiltration to Water Retention Characteristics, Initial Conditions, and Boundary Conditions

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 361
Author(s):  
Lesheng An ◽  
Kaihua Liao ◽  
Chun Liu
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Water Retention ◽  
Constant Pressure ◽  
Pressure Head ◽  
Estimation Methods ◽  
Initial Water Content ◽  
Initial Water ◽  
Cumulative Infiltration ◽  
Retention Characteristics

(1) Background: Simulation of soil water infiltration process and analysis of its influencing factors are important for water resources management. (2) Methods: In this study, the relative contributions of the soil water retention characteristics (SWRC) estimation, initial water content, and constant pressure head at upper boundary to the cumulative infiltration under various soil conditions were quantified based on the 1-D Richards’ equation and 900 scenarios. Scenario simulations were performed for two SWRC estimation methods (Jensen method and Rosetta); three different initial water contents (0.15, 0.20, and 0.25 cm3/cm3); five different constant pressure heads (0.5, 1, 2, 4, and 8 cm); and thirty soil samples with varying texture and bulk density. (3) Results: Rosetta representing the drying branch of the SWRC yielded higher simulated cumulative infiltration compared with the Jensen method representing the wetting branch of the SWRC. However, the Jensen method–predicted cumulative infiltration fluxes matched well with the measured values with a low RMSE of 0.80 cm. (4) Conclusions: The relative contribution of the SWRC estimation method to cumulative infiltration (19.1–72.2%) was compared to that of constant pressure head (14.0–65.5%), and generally greater than that of initial water content (2.2–29.9%). Findings of this study have practical significance for investigating the transport of water, nutrients, and contaminants in the unsaturated zone.

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.

Sign in / Sign up

Export Citation Format

Share Document