scholarly journals Strength and Volume Change Characteristics of Clayey Soils: Performance Evaluation of Enzymes

Minerals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 52
Author(s):  
Tanveer Ahmed Khan ◽  
Mohd Raihan Taha ◽  
Mudasser Muneer Khan ◽  
Syyed Adnan Raheel Shah ◽  
Muhammad Asif Aslam ◽  
...  
Keyword(s):  
Volume Change ◽  
Unconfined Compressive Strength ◽  
Optimum Moisture Content ◽  
Soil Samples ◽  
Residual Soil ◽  
Clayey Soils ◽  
X Ray Diffraction ◽  
Treated Soil ◽  
X Ray ◽  
Change Characteristics

This study was conducted to evaluate the strength and volume change characteristics of a sedimentary residual soil mixed with bentonite (S1) when treated with three different enzymes. In addition, three reference clays including bentonite, illite, and kaolinite were also treated with enzymes to study the effect on their strength characteristics. Soil samples prepared at the optimum moisture content (OMC) were sealed and cured for four months. After curing, reference clays were tested for unconfined compressive strength (UCS). For swell tests, the S1 soil samples were placed on porous stones, which were immersed in water to allow capillary soaking of the samples. S1 samples were allowed to dry at ambient temperature for shrinkage test until the rate of reduction in volume became negligible. On completion of swell tests, the samples were tested for UCS to determine the decrease in strength due to saturation. No increase in strength and decrease in volume change were observed for any of the enzymes and dosages. Field Emission Scanning Electron Microscope (FESEM) showed some dense packing of particles for treated samples, whereas X-ray diffraction (XRD) did not reveal any change; in fact, the pattern for untreated and treated soil samples were indistinguishable.

scholarly journals Effect of Three Bioenzymes on Compaction, Consistency Limits, and Strength Characteristics of a Sedimentary Residual Soil

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Tanveer Ahmed Khan ◽  
Mohd Raihan Taha
Keyword(s):  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Soil Improvement ◽  
Soil Samples ◽  
Atterberg Limits ◽  
Residual Soil ◽  
X Ray Diffraction ◽  
Compaction Characteristics ◽  
X Ray ◽  
Curing Period

Bioenzymes are organic degradable materials, currently introduced as soil improvement additives. In this experimental study, three types of bioenzymes from three different countries were used to improve Universiti Kebangsaan Malaysia (UKM) soil. UKM soil has properties quite similar to soils recommended as suitable by bioenzyme suppliers. The effect of the three bioenzymes on Atterberg limits, compaction characteristics, and unconfined compressive strength was studied. Controlled untreated and treated samples for two dosages at curing times up to three months were prepared and tested after completion of the curing period. Some results showed little improvement in compaction characteristics, and unconfined compressive strength, but no notable improvement was noticed in Atterberg limits. X-ray diffraction (XRD), X-ray fluorescence (XRF), and field emission scanning electron microscopy (FESEM) tests were conducted for untreated and treated soil samples after two months of curing. XRD and XRF did not show any change in mineralogy and chemical composition between controlled untreated samples and samples treated with the three bioenzymes. However, the FESEM images revealed a denser packing of particles for soil samples treated with two of the bioenzymes.

Preparation and Properties of Lime-Based Curing Material for Soil

2014 ◽  
Vol 507 ◽  
pp. 449-454
Author(s):  
Jian Ping Long ◽  
Ying Zeng
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Soil Samples ◽  
X Ray Diffraction ◽  
Treated Soil ◽  
X Ray ◽  
Curing Agents

Four types of curing agents were added into the soil at different ratios. Then the treated soil samples were molded. The compressive strengths of the soil samples were determined at different curing ages. The samples were detected by the X-ray diffraction (XRD) and thermogravimetry / differential thermal analysis (TGDTA). The results indicated that the curing agents A and C used in the experiment had a significant improving effect on the strength of the soil.

scholarly journals Changes in mineralogy and microstructure of a lime-treated silty soil during curing time

2020 ◽  
Vol 195 ◽  
pp. 03044
Author(s):  
Zi YING ◽  
Yu-jun Cui ◽  
Nadia Benahmed ◽  
Myriam Duc
Keyword(s):  
Mercury Intrusion Porosimetry ◽  
Soil Samples ◽  
Time Effect ◽  
Curing Time ◽  
X Ray Diffraction ◽  
Lime Treatment ◽  
Treated Soil ◽  
X Ray ◽  
Mercury Intrusion

Lime treatment is widely applied to improve the workability and long-term durability of soils. In this study, the curing time effect on the mineralogy and microstructure of lime-treated soil was investigated. The soil samples were prepared with 2 % lime and statically compacted at dry (w = 17 %) and wet (w = 20%) sides of optimum. X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) were performed on lime-treated soil at various curing times. The presence of XRD peaks attributed to portlandite even after 150 days curing time indicated that it was not totally converted in cementitious compounds after reaction with silica and alumina from clay minerals. By contrast, no obvious XRD reflections of well-crystallized cementitious compounds were identified. Furthermore, all samples compacted at dry and wet side of optimum exhibited bi-modal pore size distribution, with a decrease of macro-pore frequency with increasing water content. The microstructure changes with increasing curing time did not follow monotonic tendency. On the whole, the quantities of pores less than 0.006 μm and micro-pores increased and the quantity of macro-pores decreased with increasing curing time due to the possible creation of poorly crystallized or amorphous cementitious compounds.

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 Strength and Solidification Mechanism of Silt Solidified by Polyurethane

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Fengyuan Li ◽  
Chaojie Wang ◽  
Yangyang Xia ◽  
Yanjie Hao ◽  
Peng Zhao ◽  
...  
Keyword(s):  
Unconfined Compressive Strength ◽  
Immersion Time ◽  
Mercury Intrusion Porosimetry ◽  
Polymer Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mercury Intrusion ◽  
Grouting Material ◽  
Permeable Polymer ◽  
Solidification Mechanism

To determine the mechanism and strength characteristics of solidification of silt by a permeable polyurethane grouting material, the effects of polymer content, soil moisture, and immersion time on the unconfined compressive strength (UCS) of the silt have been studied. The results showed that the permeable polymer grouting material can significantly improve the performance of silt: (1) A higher amount of polymer produced a greater strength in the solidified soil. (2) The strength of the solidified soil increased as the immersion time was increased. (3) Moisture in the soil was not conducive to improving the strength of the solidified soil. The X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) have proven that polyurethane does not react with the silt, but they could improve the strength of the silt through physical action. Mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) were performed to find that polymers can reduce soil porosity, and the addition of polyurethane improved the strength of the silt mainly through adhesion, wrapping, filling, and bridging.

Characterization of mineral phases of agricultural soil samples of Colombian coffee using Mössbauer spectroscopy and X-ray diffraction

ICAME 2011 ◽  
2012 ◽  
pp. 593-598
Author(s):  
Humberto Bustos Rodríguez ◽  
Dagoberto Oyola Lozano ◽  
Yebrayl Antonio Rojas Martínez ◽  
Marlene Rivera Pinilla ◽  
German Antonio Pérez Alcázar
Keyword(s):  
Mössbauer Spectroscopy ◽  
Agricultural Soil ◽  
Mossbauer Spectroscopy ◽  
Soil Samples ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mößbauer Spectroscopy ◽  
Mineral Phases

scholarly journals Engineering behaviour of stabilized laterite and kaolin using lignin

2018 ◽  
Vol 250 ◽  
pp. 01008
Author(s):  
Tuan Noor Hasanah Tuan Ismail ◽  
Siti Aimi Nadia Mohd Yusoff ◽  
Ismail Bakar ◽  
Devapriya Chitral Wijeyesekera ◽  
Adnan Zainorabidin ◽  
...  
Keyword(s):  
Moisture Content ◽  
Unconfined Compressive Strength ◽  
Laboratory Tests ◽  
Dry Weight ◽  
Optimum Moisture Content ◽  
Soil Samples ◽  
Dry Density ◽  
Laterite Soil ◽  
Maximum Dry Density ◽  
Steady Rate

Soils at many sites do not always have enough strength to bear the structures constructed over them and some of the soil may need to be stabilized in order to improve their geotechnical properties. In this paper, routine laboratory tests were critically carried out to investigate the efficacy of lignin in improving the strength behaviour of the soils. Two different soil samples (laterite and kaolin) were studied and mixed with different proportions of lignin (2% and 5% of dry weight of soil), respectively. Unconfined Compressive Strength (UCS) characteristics evaluated in this study were done on samples at their maximum dry density and optimum moisture content (obtained from compaction tests). The UCS tests on all the specimens were carried out after 0, 7, 15, 21 and 30 days of controlled curing. The research results showed that the addition of lignin into kaolin reduced its maximum dry density while giving progressively higher optimum moisture content. Contrarily, with the laterite soil, both maximum dry density and optimum moisture content simultaneously increased when lignin was added into the soils. The UCS results showed that the the stabilized laterite with 2% lignin continued to gain strength significantly at a fairly steady rate after 7 days. Unfortunately, lignin did not show a significant effect in kaolin.

Halloysite in some soils from north-east Scotland

Clay Minerals ◽  
1977 ◽  
Vol 12 (1) ◽  
pp. 59-66 ◽  
Author(s):  
M. J. Wilson ◽  
J. M. Tait
Keyword(s):  
Electron Microscopy ◽  
Electron Diffraction ◽  
Soil Samples ◽  
X Ray Diffraction ◽  
X Ray ◽  
Drainage Class ◽  
North East ◽  
Parent Rocks ◽  
Diffraction Patterns

AbstractX-ray diffraction and electron microscopy show that halloysite occurs widely in soils derived from a variety of parent rocks (granite, gabbro, schist and slate) in north-east Scotland. Both tubular and non-tubular forms are observed, the latter being characterized by electron diffraction patterns with 001 reflection either absent or very weak and diffuse. Clay fractions from a poorly drained profile separated without prior drying of the soil samples contain essentially dehydrated halloysite at the surface, this becoming progressively more hydrated with depth. Since halloysite occurs extensively in soils of widely varying drainage class the mineral is probably not the result of recent soilforming processes but may have originated during Tertiary or interglacial weathering.

Effect of zeolitization on the volume-change behaviour of kaolinitic soils

2006 ◽  
Vol 43 (9) ◽  
pp. 969-978 ◽  
Author(s):  
P V Sivapullaiah ◽  
M Manju
Keyword(s):  
Volume Change ◽  
Alkali Solution ◽  
Time Lags ◽  
X Ray Diffraction ◽  
X Ray ◽  
Alkali Solutions ◽  
Zeolite Formation ◽  
Interaction Period

An attempt has been made to study the effect of zeolite formation on the volume-change behaviour of kaolinitic soil. This is studied in terms of two criteria, namely concentration and period of interaction. Conventional consolidation tests have been carried out to determine the extent of change in swell and compressibility of kaolinitic soils remoulded with water and inundated with an alkali solution. It was observed that abnormal swell occurs during unloading when specimens were inundated with a 4N alkali solution. While allowing a longer interaction period at 6.25 kPa, it was found that swelling in kaolinitic soils is induced after time lags of 30 and 15 days on inundation with 1N and 4N alkali solutions, respectively. Equilibrium is reached after 50–70 days in kaolinitic soils, however, and loading was undertaken later. A 16% swelling was observed in kaolinitic soils when inundated with a 4N alkali solution, indicating that zeolitization of kaolinite results in swelling at the seating load provided the period of interaction is sufficient. X-ray diffraction studies confirm the formation of zeolite.Key words: alkali, consolidation, kaolinite, swelling, X-ray diffraction, zeolite.

Sign in / Sign up

Export Citation Format

Share Document