Multiple Thixotropisms of Liquid Limit–Consistency Clays Unraveled by Multiscale Experimentation

AbstractInvestigation into the cause of road failure has been carried out along a 60 km long Sagamu –Papalanto highway southwestern Nigeria. Geochemical, mineralogical, geotechnical and geophysical analyses were conducted to evaluate the cause of failure along the study area. The results of the laboratory tests showed that the percentage amount of fines ranges from 12 to 61.3%, natural moisture content from 6.8 to 19.7%, liquid limit in the range of 25.1–52.2%, linear shrinkage between 3.96 to 12.71%, plastic limit ranges from 18.2–35%, plasticity index ranges from 5.2 to 24.6%, free swell in the range from 5.17–43.9%, maximum dry density ranges from 1.51–1.74 g /cm3, specific gravity ranges from 2.52–2.64 and CBR between 3 and 12%. The Cone Penetrometer Test (CPT) shows a resistance value of 20–138 kgf/cm2. The major clay mineral that is predominant in the studied soil is kaolinite. The major oxides present are SiO2, Al2O3, Fe2O3, K2O, Na2O, MgO and CaO. The result of the 2D Electrical Resistivity Imaging revealed a low resistivity values for profile 2 and 3 ranging from 100 Ωm – 300 Ωm, between a distance of 20 m – 240 m along the profile to a depth of 7.60 m and a low resistivity value ranging from 50 Ωm – 111Ωm, between a distance of 80 m − 120 m along the profile to a depth of 15 m. It was concluded that the low CBR, low MDD and the class of subsoils namely A-26, A-7, A-2-7 (clayey soils) which were identified are responsible for the cause of failure experienced in the study area. These makes the soils unsuitable as road construction materials and hence, there is need for stabilization during the reconstruction and rehabilitation of the road.

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The relationship between geotechnical index properties and the pore-size distribution of compacted clayey silts

Science and Engineering of Composite Materials ◽

10.1515/secm-2013-0302 ◽

2015 ◽

Vol 22 (6) ◽

Author(s):

Nazile Ural

Keyword(s):

Specific Surface ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Correlation Coefficients ◽

Liquid Limit ◽

Index Properties

AbstractIn this study, the relationships between geotechnical index properties and the pore-size distribution of compacted natural silt and artificial soil mixtures, namely, silt with two different clays and three different clay percentages (10%, 20%, and 40%), were examined and compared. Atterberg’s limit tests, standard compaction tests, mercury intrusion porosimetry, X-ray diffraction, scanning electron microscopy (SEM) analysis, and Brunauer-Emmett-Teller specific surface analysis were conducted. The results show that the liquid limit, the cumulative pore volume, and specific surface area of artificially mixed soils increase with an increase in the percentage of clay. The cumulative pore volume and specific surface area with geotechnical index properties were compared. High correlation coefficients were observed between the specific areas and both the liquid limit and the plasticity index, as well as between the cumulative pore volume and both the clay percentage and the

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Compressibility behaviour of remoulded, fine-grained soils and correlation with index properties

Canadian Geotechnical Journal ◽

10.1139/t99-128 ◽

2000 ◽

Vol 37 (3) ◽

pp. 712-722 ◽

Cited By ~ 93

Author(s):

A Sridharan ◽

H B Nagaraj

Keyword(s):

Liquid Limit ◽

Plasticity Index ◽

Engineering Properties ◽

Test Results ◽

Index Properties ◽

Initial Water ◽

Fine Grained ◽

Wide Range ◽

The Relationship ◽

Water Contents

Correlating engineering properties with index properties has assumed greater significance in the recent past in the field of geotechnical engineering. Although attempts have been made in the past to correlate compressibility with various index properties individually, all the properties affecting compressibility behaviour have not been considered together in any single study to examine which index property of the soil correlates best with compressibility behaviour, especially within a set of test results. In the present study, 10 soils covering a sufficiently wide range of liquid limit, plastic limit, and shrinkage limit were selected and conventional consolidation tests were carried out starting with their initial water contents almost equal to their respective liquid limits. The compressibility behaviour is vastly different for pairs of soils having nearly the same liquid limit, but different plasticity characteristics. The relationship between void ratio and consolidation pressure is more closely related to the shrinkage index (shrinkage index = liquid limit - shrinkage limit) than to the plasticity index. Wide variations are seen with the liquid limit. For the soils investigated, the compression index relates better with the shrinkage index than with the plasticity index or liquid limit.Key words: Atterberg limits, classification, clays, compressibility, laboratory tests.

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Hydraulic Conductivity of Polymer-Amended Sand-Bentonite Backfills Permeated with Lead Nitrate Solutions

Advances in Civil Engineering ◽

10.1155/2018/9435194 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Sheng-Qiang Shen ◽

Ming-Li Wei

Keyword(s):

Hydraulic Conductivity ◽

Water Content ◽

Applied Pressure ◽

Lead Nitrate ◽

Bound Water ◽

Liquid Limit ◽

Filter Press ◽

Diffuse Double Layer ◽

Comparison Results ◽

Pb Concentration

Hydraulic conductivity of sand-bentonite (SB) backfills amended with polyanionic cellulose (PAC) to lead nitrate (Pb(NO3)2) solutions was evaluated experimentally in this study. PAC-amended sand-bentonite (PSB) backfills were synthesized by mixing sand-bentonite mixture with 0.3 to 1.2% dry PAC (by total dry mixture mass) and mixed with a certain weight of conventional bentonite (CB) slurry. The rheology properties including the filtrate loss, viscosity, density, and pH testes of slurry with various bentonite dosages were measured to determine the reasonable CB dosage of slurry. The slump tests on PSB backfills with various mass slurries were conducted to determine the corresponding water content of backfills with slump 125 ± 5 mm. Under the applied pressure 100 kPa, the hydraulic conductivity to Pb(NO3)2 solutions (kc) of PSB backfills with various PAC contents was evaluated based on the modified filter press (MFP) tests, to ascertain the optimum PAC content of PSB backfills when permeated with Pb(NO3)2 solutions. Index properties, including the specific gravity (Gs) and liquid limit (wL) of PSB backfills, were measured after MFP tests. The MFP tests for PSB backfills were then conducted under various applied pressures to obtain the relationship between void ratio (e) and hydraulic conductivity of backfills. Finally, the flexible-wall permeability test (FWP test) under osmotic pressure 100 kPa was conducted to verify the effectiveness of the MFP test. The results indicate that slurry with 8% bentonite dosage is the reasonable choice in slurry wall construction. PSB has lower GS and higher wL compared to SB; increasing Pb concentration leads to GS of PSB increased and wL of PSB decreased. PSB with 0.6% PAC content is supposed as the optimum proportion of backfills when permeated with concentrated Pb(NO3)2 solution. PAC adsorbs large amount of bound water, which leads to higher water content (w) and e of PSB backfills, while lead ions (Pb) cause the diffuse double layer (DDL) of bentonite compressed and e of PSB backfills reduced. The kc of PSB-0.6 remains lower than 10−9 m/s and increases less than 10 times though the Pb concentration was up to 500 mM, demonstrating that the hydraulic performance of backfills can be improved effectively in Pb(NO3)2 solution by the additive PAC. The comparison results between k from MFP tests and FWP tests show that the MFP test is an effective and easy evaluation of hydraulic conductivity of backfills.

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Comparison of liquid limit values determined using the hard and soft base Casagrande apparatus and the cone penetrometer

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-009-0191-4 ◽

2009 ◽

Vol 68 (3) ◽

pp. 289-296 ◽

Cited By ~ 20

Author(s):

Mustafa Özer

Keyword(s):

Liquid Limit ◽

Cone Penetrometer ◽

Limit Values

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Geotechnical properties of reinforced clayey soil using nylons carry’s bags by products

MATEC Web of Conferences ◽

10.1051/matecconf/201816201020 ◽

2018 ◽

Vol 162 ◽

pp. 01020 ◽

Cited By ~ 1

Author(s):

Nahla Salim ◽

Kawther Al-Soudany ◽

Nora Jajjawi

Keyword(s):

Soil Stabilization ◽

Clayey Soil ◽

Ground Improvement ◽

Soft Soil ◽

Liquid Limit ◽

Waste Material ◽

Industrial Wastes ◽

Dry Density ◽

Maximum Dry Density ◽

Replacement Technique

All structures built on soft soil may experience uncontrollable settlement and critical bearing capacity. This may not meet the design requirements for the geotechnical engineer. Soil stabilization is the change of these undesirable properties in order to meet the requirements. Traditional methods of stabilizing or through in-situ ground improvement such as compaction or replacement technique is usually costly. Now a safe and economic disposal of industrial wastes and development of economically feasible ground improvement techniques are the important challenges being faced by the engineering community. This work focuses on improving the soft soil brought from Baghdad by utilizing the local waste material for stabilization of soil, such as by using “Nylon carry bag’s by product” with the different percentage and corresponding to 1 %, 3% and 5% (the portion of stabilizer matters to soil net weight) of dried soil. The results indicated that as Nylon’s fiber content increases, the liquid limit decreases while the plastic limit increases, so the plasticity index decreases. Furthermore, the maximum dry density decreases while, the optimum moisture content increases as the Nylon’s fiber percentage increases. The compression index (decreases as the Nylon’s fiber increases and provides a maximum of 43% reduction by adding 5% nylon waste material. In addition, the results indicated that, the undrained shear strength increases as the nylon fiber increases.

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Packaged Droplet Microresonator for Thermal Sensing with High Sensitivity

Sensors ◽

10.3390/s18113881 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3881 ◽

Cited By ~ 9

Author(s):

Xiaogang Chen ◽

Liang Fu ◽

Qijing Lu ◽

Xiang Wu ◽

Shusen Xie

Keyword(s):

Liquid Droplet ◽

Thermal Sensitivity ◽

High Sensitivity ◽

Liquid Limit ◽

Practical Applications ◽

Sensing Applications ◽

Cavity Structure ◽

Thermal Sensing ◽

Facile Fabrication ◽

Definition Of

Liquid droplet and quasi-droplet whispering gallery mode (WGM) microcavities have been widely studied recently for the enhanced spatial overlap between the liquid and WGM field, especially in sensing applications. However, the fragile cavity structure and the evaporation of liquid limit its practical applications. Here, stable, packaged, quasi-droplet and droplet microcavities are proposed and fabricated for thermal sensing with high sensitivity. The sensitivity and electromagnetic field intensity distribution are analyzed by Mie theory, and a quantified definition of the quasi-droplet is presented for the first time to the best of our knowledge. By doping dye material directly into the liquid, lasing packaged droplet and quasi-droplet microcavity sensors with a high thermal sensitivity of up to 205.3 pm/°C are experimentally demonstrated. The high sensitivity, facile fabrication, and mechanically robust properties of the optofluidic, packaged droplet microresonator make it a promising candidate for future integrated photonic devices.

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Effects of High Plasticity and Expansive Clay Stabilization with Lime on UCS Testing in Several Conditions

Journal of the Civil Engineering Forum ◽

10.22146/jcef.59438 ◽

2021 ◽

Vol 1000 (1000) ◽

Author(s):

Soewignjo Agus Nugroho ◽

Gunawan Wibisono ◽

Andarsin Ongko ◽

Avrilly Zesthree Mauliza

Keyword(s):

Soil Stabilization ◽

Soft Soil ◽

Fine Powder ◽

High Water ◽

Liquid Limit ◽

Clay Soils ◽

High Water Content ◽

High Plasticity ◽

Expansive Clay ◽

Limit Value

Clay is a cohesive and very soft soil if it has high water content. To overcome this problem, clay soils with high plasticity need to be stabilized. The method of soil stabilization with lime is an alternative effort to improve soil that does not meet the standards. Lime reacts with groundwater so that it changes the property of the soil, reducing the stickiness and softness of the soil. Lime also functions to solidify (stabilize) and stabilize (stabilize) soil in the form of fine powder consisting of metals and inorganic mineral composition. This study aims to determine the effect of clay soils when carried out stabilization by using a limestone additive which varies in levels of mixture. The results showed that lime effective for the stabilization high plasticity and expansive clay by increasing the compressive strength value of UCS with lime content of 10% under curing conditions in 28 days and unsoaked by 319%, the liquid limit value reduced by 6% and the plastic limit value increased by 46%.

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