scholarly journals Improvement of Engineering Properties of Residual Soil of Tuff Breccia by Electro-Kinetic Method

2018 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Hnin Thazin Aung ◽  
Doni Prakasa Eka Putra ◽  
I Gde Budi Indrawan
Keyword(s):  
Ph Value ◽  
Kinetic Method ◽  
Soil Samples ◽  
Engineering Properties ◽  
Residual Soil ◽  
Electrokinetic Method ◽  
Kinetic Treatment ◽  
Tuff Breccia ◽  
Natural Slopes ◽  
Mineral Changes

This paper presents the results of an experimental study that was conductedto improve engineering properties of residual soil of tuff breccia by applying the electrokinetic method. The soil samples were taken from a slope in a high susceptible landslide area in the Kulon Progo, Yogyakarta, Indonesia. The electro-kinetic experiments were conducted using a clear glass tank of 60 cm 30 cm 30 cm size, a 13 V power pack to supply the voltage, and aluminum electrodes. The results showed that the pH value of anolyte decreased while that of catholyte increased during the treatment. The Atterberg’s limits of all soil samples decreased, while the shear strengths increased. XRD and SEM analyses indicated that there were no mineral changes after electro-kinetic experiments. However, the soil structure changed and became denser. The increased soil strength after electro-kinetic treatment would likely improve stability of natural slopes.

scholarly journals Describing Phosphorus Sorption Processes on Volcanic Soil in the Presence of Copper or Silver Engineered Nanoparticles

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 373
Author(s):  
Jonathan Suazo-Hernández ◽  
Erwin Klumpp ◽  
Nicolás Arancibia-Miranda ◽  
Patricia Poblete-Grant ◽  
Alejandra Jara ◽  
...  
Keyword(s):  
Organic Matter ◽  
Crop Production ◽  
Agricultural Soils ◽  
Ph Value ◽  
Consumer Products ◽  
Soil Samples ◽  
Engineered Nanoparticles ◽  
P Availability ◽  
Agricultural Crop ◽  
Phosphorus Sorption

Engineered nanoparticles (ENPs) present in consumer products are being released into the agricultural systems. There is little information about the direct effect of ENPs on phosphorus (P) availability, which is an essential nutrient for crop growthnaturally occurring in agricultural soils. The present study examined the effect of 1, 3, and 5% doses of Cu0 or Ag0 ENPs stabilized with L-ascorbic acid (suspension pH 2–3) on P ad- and desorption in an agricultural Andisol with total organic matter (T-OM) and with partial removal of organic matter (R-OM) by performing batch experiments. Our results showed that the adsorption kinetics data of H2PO4− on T-OM and R-OM soil samples with and without ENPs were adequately described by the pseudo-second-order (PSO) and Elovich models. The adsorption isotherm data of H2PO4− from T-OM and R-OM soil samples following ENPs addition were better fitted by the Langmuir model than the Freundlich model. When the Cu0 or Ag0 ENPs doses were increased, the pH value decreased and H2PO4− adsorption increased on T-OM and R-OM. The H2PO4− desorption (%) was lower with Cu0 ENPs than Ag0 ENPs. Overall, the incorporation of ENPs into Andisols generated an increase in P retention, which may affect agricultural crop production.

Macrostructural and Microstructural Properties of Residual Soils as Engineered Landfill Liner Materials

2021 ◽  
Author(s):  
Lee Li Yong ◽  
Vivi Anggraini ◽  
Mavinakere Eshwaraiah Raghunandan ◽  
Mohd. Raihan Taha
Keyword(s):  
Tap Water ◽  
Chemical Precipitation ◽  
Soil Samples ◽  
Residual Soil ◽  
Diffuse Double Layer ◽  
Microstructural Properties ◽  
Residual Soils ◽  
Soil Leachate ◽  
Landfill Liner ◽  
X Ray

ABSTRACT This study assessed the performance of residual soils with regard to their macrostructural and microstructural properties and compatibility with leachate in pursuit of exploring alternative cost-effective and efficient landfill liner materials. A series of laboratory investigations was conducted on three residual soil samples by using tap water and leachate as permeation fluid to achieve the objectives of the study. The zeta potential measurements revealed that the presence of multivalent cations in the leachate decreased the diffuse double layer (DDL) thickness around the soil particles. The reduced DDL thickness caused a decrease in Atterberg limits of soil-leachate samples and changes in the classification of fine fractions. Additionally, the effects of pore clogging attributed to chemical precipitation and bioclogging were responsible for the reduction in measured hydraulic conductivities of soil-leachate samples. These effects can be clearly observed from the field-emission scanning electron microscopy images of soil-leachate samples with the appearance of less visible voids that led to a more compact and dense structure. The formation of new non-clay minerals and associated changes in the Al and Si ratio as reflected in the x-ray diffraction diffractograms and energy-dispersive x-ray analyses, respectively, were attributed to the effects of chemical precipitation. This study concluded that S1 and S2 residual soil samples are potential landfill liner materials because they possess adequate grading characteristics, adequate unconfined compressive strength, low hydraulic conductivity, and good compatibility with leachate. In contrast, the S3 sample requires further treatment to enhance its properties in order to comply with the requirements of landfill liner materials.

scholarly journals Variation in Salinity through the Soil Profile in South Coastal Region of Bangladesh

2018 ◽  
Vol 42 (1) ◽  
pp. 11-23
Author(s):  
Mohammad Asadul Haque
Keyword(s):  
Electrical Conductivity ◽  
Salt Stress ◽  
Soil Profile ◽  
Ph Value ◽  
Soil Depth ◽  
Coastal Region ◽  
Soil Samples ◽  
Salt Accumulation ◽  
Top Soil ◽  
Academy Of Sciences

The spatial variability of salt accumulation through the soil profile was studied at Latachapali union of Kalapara upazila, Patuakhali district, Bangladesh. The soil samples were collected from 30 locations covering six villages of the union: Kuakata, Malapara, Fashipara, Khajura, Mothaopara and Tajepara. Five locations were randomly selected from each village. From each location soil samples were collected from three soil depths at 0-2 cm, 2.1-4 cm and 4.1-6 cm. Electrical conductivity of top 0-2 cm soil depth was 20.49 dS/m, in 2.1-4 cm soil depth was 7.14 dS/m and in 4.1-6 cm soil depth 4.15 dS/m. The study soils were strongly acidic having pH value 4.73, 4.99 and 5.20 in 0-2, 2.1-4 and 4.1-6 cm soil depth, respectively. The highest of 8.8 Na:K ratio was found in 0-2 cm soil depth. The Na:K ratio gradually decreased with the increase of soil depth, having 6.59 in 2.1-4 cm and 5.42. in 4.1-6 cm soil depth. The results clearly reveal that the top soil is very much sensitive to salt stress. Based on the electrical conductivity and Na:K ratio the Fashipara, Kuakata and Tajepara village were found seriously affected by salinity.Journal of Bangladesh Academy of Sciences, Vol. 42, No. 1, 11-23, 2018

scholarly journals Appraisal of Geotechnical Characteristics of Ormara Soil, Baluchistan, Pakistan

2019 ◽  
Vol 10 (3) ◽  
pp. 22-26
Author(s):  
Abdul Jabbar Khan ◽  
Naveed Ahsan ◽  
Muhammad Sanaullah ◽  
Gulraiz Akhter
Keyword(s):  
Triaxial Compression ◽  
Liquid Limit ◽  
Soil Samples ◽  
Engineering Properties ◽  
Clay Layer ◽  
Compression Tests ◽  
Geotechnical Characteristics ◽  
Density Values ◽  
Construction Plans ◽  
Triaxial Compression Tests

Ormara is located 240 km west of Karachi which is a coastal and port city (25° 16' 29N, 64° 35' 10E) ofPakistan. Present study evaluates engineering properties of soils of Ormara for future construction plans and possibleexpansions in the area. Fifty bore holes were done in study area at depths of 20m, 40m and some (10 bore holes) were60m deep. The study area was divided into three major zones i.e. Foot hills, on-shore and off-shore. Groundwater wasencountered at depths of 2.75m on onshore and offshore zones and at 3.65m depth in foothill zone. Laboratory testingi.e. moisture content (12 to 38 %), liquid limit (from 26 to 34), plasticity index (10 to 18) of soil samples indicate thatsoils are low plastic to moderate plastic in nature. Soil samples of granular soils indicate angles of internal friction (ø)varying from 260- 36ºin upper sand layers while 260 to 30º in lower silt layers (encountered after the clay layer) andCohesion ranges 0 to 0.04kg/cm2 in all three zones. Further, unconsolidated undrained triaxial compression tests on aclayey soil sample indicated an undrained cohesion value of 28 kPa. Density values ranges from 1.6 to 2.05gm/cm3.Consolidation (Cv = 0.20 to 0.40 cm2/minute, Cc = 0.149 to 0.17) has been calculated for clay layer. Chemical testscarried out on soil samples indicated that soil and water both are reactive aggressively and may cause corrosion to steeland concrete disintegration.

scholarly journals Research on Wetting-Drying Cycles’ Effect on the Physical and Mechanical Properties of Expansive Soil Improved by OTAC-KCl

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Bao-tian Wang ◽  
Can-hong Zhang ◽  
Xue-lian Qiu ◽  
En-yue Ji ◽  
Wen-hui Zhang
Keyword(s):  
Mechanical Properties ◽  
Expansive Soil ◽  
Physical And Mechanical Properties ◽  
Cyclic Strength ◽  
Soil Samples ◽  
Engineering Properties ◽  
Swelling Potential ◽  
Wetting And Drying ◽  
Strength Tests ◽  
Free Swell

Expansive soil experiences periodic swelling and shrinkage during the alternate wet and dry environments, which will result in severe damage to the slope stability. In this study, a promising modifier OTAC-KCl is introduced, which has a good diffusivity and is soluble in water or other solvents easily. Firstly, a reasonable combination of ameliorant 0.3% STAC and 3% KCl is chosen referring to the free swell test. Then, the best curing period, 14 days, is gotten from UCS tests. The effect of wetting and drying cycles on engineering properties of expansive soil improved by OTAC-KCl admixtures after 14-day curing is also studied accordingly. Both treated and untreated expansive soil samples are prepared for the cyclic wetting-drying tests which mainly include cyclic swelling potential and cyclic strength tests. Experimental results show that the swelling potential of expansive soil samples stabilized with OTAC-KCl is suppressed efficiently, and the untreated soil specimens will collapse when immersed in water while the treated specimens keep in good conditions. Moreover, expansive soil samples modified with 0.3% OTAC + 3% KCl show enough durability on the swelling ability, shear strength, and unconfined compressive strength, which means, that both the physical and the mechanical properties of stabilized expansive soil have been improved effectively.

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.

COMPARISON OF THE EFFICACY AND SOIL CONCENTRATIONS OF FALL- AND SPRING-APPLIED TRIFLURALIN IN FLAX

1983 ◽  
Vol 63 (4) ◽  
pp. 1031-1038 ◽  
Author(s):  
D. A. PCHAJEK ◽  
I. N. MORRISON ◽  
G. R. B. WEBSTER
Keyword(s):  
Sandy Loam ◽  
Growing Season ◽  
Soil Samples ◽  
Controlled Environment ◽  
Residual Soil ◽  
Setaria Viridis ◽  
Green Foxtail ◽  
Setaria Glauca ◽  
Loam Soil ◽  
Fall Application

The efficacy of fall and spring treatments of trifluralin (α,α-trifluoro-2,6- dinitro-N, N-diproply-p-toluidine) applied to a sandy loam soil seeded to flax and the residual soil concentrations of trifluralin during the growing season were compared over 2 yr. Fall application of trifluralin at 1.12 kg/ha caused less crop injury and resulted in better green foxtail (Setaria viridis (L.) Beauv.) control than a spring application at 0.84 kg/ha. Initial soil concentrations were higher in plots treated in the fall at 1.12 kg/ha than in plots treated in the spring at 0.84 kg/ha. Six weeks after the experiments were seeded to flax and after harvest, more trifluralin persisted in the fall-treated plots. Calculated on the basis of the amount detected at the time of seeding, an average of 31 and 30% of the trifluralin persisted until after harvest in 1978 and 1979, respectively. In controlled environment studies in which yellow foxtail (Setaria glauca L. Beauv.) was seeded into soil collected six weeks after seeding, growth of the weed was reduced more in soil that was treated in the fall compared to the spring. In soil samples taken after harvest, growth of yellow foxtail was significantly reduced only in soil that had been treated the previous fall, with about a 50% reduction resulting from the 1.12-kg/ha rate and a 90% reduction occurring from the 2.24-kg/ha rate.Key words: Setaria viridis, flax tolerance, green foxtail control, trifluralin residues

scholarly journals Ecology of Bacterial Pathogens Associated With Public Waste Dumpsites and their Public Health Consequences

2018 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Public Health ◽  
Prevalence Rate ◽  
Ph Value ◽  
Close Contact ◽  
Soil Samples ◽  
Public Health Issue ◽  
Health Consequences ◽  
Deep Soil ◽  
Dump Site ◽  
Significant Difference

Human societies generates large amount of waste routinely thus, waste has increasingly becomes a huge public health issue, if we must check the sporadic upsurge of epidemic outbreaks in our communities. Nonetheless, indiscriminate dumping of waste breeds different arrays of microorganisms that have been implicated with myriads of health hazards with massive public health consequences. Therefore; there is urgent need to understand the pathogens that are associated with a public waste dump site and its Public Health implications. This observational study explored the collection of two soil samples (surface and deep), from three different sampling stations. The samples were analysed for pH and aerobic heterotrophic bacterial counts using the standard analytic procedures. Both parametric (unpaired two sample t-test) and non-parametric (Mann Whitney U, Wilcoxon and Kruskalwallis) test statistics were performed at 5% significance level. Also descriptive statistics of frequency, percentage, mean and standard deviation and prevalence rate were also explored. The statistical analysis was done using Graphpad calculator and SPSS version 21. The mean pH value of the soils ranged from pH 6.78±0.01to 7.30±0.01with no significant difference (P > 0.05) between soil levels. Heterotrophic bacterial count ranged from 1.6x108 ±1.0x106 cfu/g soil to 4.4x108 ±5.8x106 cfu/g soil. However, there was a significant difference (P < 0.05) between surface and deep soil samples. However, frequency distribution and prevalence rate revealed the probable isolates in a decreasing prevalence order Nonetheless, of Bacillus spp52 (29.4%)> Proteus spp50 (28.3%)>Klebsiellaspp37 (20.9%)>Staph auerus27 (15.3%)>Pseudomasspp6 (3.4%)> Staph. Spp5 (2.8%). The common diseases caused by these microbes range from zoonotic diseases such as Anthrax to urinary trait infections, food borne infection, wound infection and septicaemia respectively. It is therefore very critical that students and University staff in close contact with any of these dumpsites with these associated public health pathogens are at risk of acquiring the above illness thus, there is urgent need for proper waste management and smart sanitation strategy intervention in the region.

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