Influence of Water Content and Dry Density on Electric and Electromagnetic Properties of a Compacted Fine-grained Soil

To determine the degree of compaction of subgrades filled with fine-grained soil, the compaction test and light dynamic penetrometer (LDP) test were carried out for low liquid-limit clay samples with different water contents in laboratory. Then, a prediction equation of the penetration ratio (PR) defined as the depth per drop of the hammer of LDP, degree of compaction (K), and water content (ω) was built. After that, the existing fine-grained soil subgrades on LDP-based field tests were excavated. The on-site PR values, water contents, and degrees of compaction of slopes were obtained. The estimated degrees of compaction using the prediction equation were compared with measured values of the degree of compaction in field. The results show that there is good consistency between them, and an error within 3.5% was obtained. In addition, the water content should be determined firstly while using the prediction equation which is proposed in this study. Therefore, a numerical method of the water content of a subgrade was developed, and the predicted and measured water contents were compared, which shows a relatively high relativity. Then, the degree of compaction of fine-grained soil subgrades can be calculated according to the predicting equation, which involves the penetration ratio (PR) and the numerically calculated water content as input instead of the measured value in the field.

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Freezing–Thawing Behavior of Lime Treated Fine–grained Soil

Academic Journal of Nawroz University ◽

10.25007/ajnu.v7n4a273 ◽

2018 ◽

Vol 7 (4) ◽

pp. 75

Author(s):

Abdulrahman Aldaood ◽

Amina Khalil ◽

Marwen Bouasker ◽

Muzahim Al-Mukhtar

Keyword(s):

Compressive Strength ◽

Water Content ◽

Unconfined Compressive Strength ◽

Soil Samples ◽

Treated Soil ◽

Freeze Thaw ◽

Fine Grained ◽

Mineralogical Properties ◽

Fine Grained Soil ◽

The Impact

This research study was carried out to investigate the impact of freeze-thaw cycles on the mechanical and the mineralogical properties of lime treated fine-grained soil. The unconfined compressive strength, wave velocity, volume change, water content, pH and electrical conductivity values were determined during freeze-thaw cycles. Furthermore, Mercury porosimetry and X-ray diffraction tests were carry out to determine changes at microscopic level. The soil used in this study was taken at a site near Jossigny region in eastern part of Paris–France. The soil samples were treated with optimum lime percent 3% depending on the pH method, then cured for 28 days at 20 °C. The soil samples were subjected to 12 cycles of freeze-thaw following ASTM procedure. The result referred that, natural soil exhibit no strength resistance against freeze-thaw cycles and failed during the first hours of freeze-thaw cycles. Analyses indicated that freeze-thaw cycles reduce the unconfined compressive strength of all the tested samples. Moreover, water content during the applied cycles increases and induces significant volume changes. During freeze-thaw cycles, the cracks propagation which caused by the formation of ice lenses in the pores of lime treated soil samples were consider to have significant. The changes in the micro-structural and mineralogical properties reduce the durability of the lime treated soil samples when subjected to freeze-thaw cycles.

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Influence of water content on the shear strength parameters of clayey soil in relation to stability analysis of a hillside in Brno region

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201361061583 ◽

2013 ◽

Vol 61 (6) ◽

pp. 1583-1588 ◽

Cited By ~ 4

Author(s):

Kristýna Bláhová ◽

Lenka Ševelová ◽

Pavla Pilařová

Keyword(s):

Shear Strength ◽

Stability Analysis ◽

Water Content ◽

Clayey Soil ◽

Friction Angle ◽

Dry Density ◽

Stability Analyses ◽

Influence Of Water ◽

Moisture Conditions ◽

Processing Stability

Shear strength of soils is highly affected by moisture conditions (i.e. water content), especially if the soil contains clay materials. Usually the laboratory specimen, which are used to determine shear strength of soil are prepared at water content and dry density same as in the field conditions, without respect to the fact, that the conditions in the future might not remain the same. For the purpose of this study soil specimen were compacted and the optimum moisture content was identified. After compaction soil was tested at the dry side of optimum water content at w = 9 %, 10 % and 11 %. Parameters of shear strength were obtained and used for stability analysis with software GEOSLOPE/W 2012. According to referenced literature, it was expected for the shear strength of the soil to decrease with increasing water content. This hypothesis was not proven for clayey soil from Brno region. Development of values of friction angle and cohesion exhibited anomalous behaviour and such development was found also for values of Factor of safety (FOS) obtained from stability analyses. Results proved the necessity of taking moisture conditions into account, when processing stability analyses, in order to achieve reliable and safe constructions.

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Permeability of the Mixture of Fine Grained Soil and Fly Ash from Fluidized Bed Combustion

Transactions of the VŠB - Technical University of Ostrava Civil Engineering Series ◽

10.1515/tvsb-2017-0023 ◽

2017 ◽

Vol 17 (2) ◽

pp. 25-30

Author(s):

Karolina Knapik ◽

Joanna Bzówka

Keyword(s):

Fly Ash ◽

Water Content ◽

Fluidized Bed ◽

Initial Water Content ◽

Curing Time ◽

Fluidized Bed Combustion ◽

Initial Water ◽

Fine Grained ◽

Fine Grained Soil ◽

Fbc Fly Ash

Abstract Based on known correlations permeability was calculated for the mixtures containing various proportions of selected FBC fly ash, Speswhite kaolin and lime. The influence of initial water content of the mixtures was also considered. The study was limited to the first four weeks of curing time. Results of calculations were discussed on the background of previously obtained observations for mixtures of tested materials.

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Field Test Study on Frost-Heave of Subgrade in Seasonal Frozen Region along Haerbin-Dalian Passenger Dedicate Line

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.671-674.45 ◽

2013 ◽

Vol 671-674 ◽

pp. 45-49 ◽

Cited By ~ 1

Author(s):

Jin Fang Hou ◽

Yong Li Wang ◽

Jun Feng

Keyword(s):

Soil Temperature ◽

Water Content ◽

Field Test ◽

Frost Heave ◽

Soil Pressure ◽

Construction Technique ◽

Effective Measure ◽

Fine Grained ◽

Environment Temperature ◽

Fine Grained Soil

The new constructing railway Haerbin-Dalian Dedicate Line runs through the typical seasonal frozen region. For the purpose of estimating the quality of subgrade construction, a field test was played. Placed the monitoring instrument and measure the soil temperature, settlement and soil pressure etc.. The monitoring data shows that the change of soil temperature is less than the environment temperature. The maximum frost depth is 1.66m. In this depth, the fine-grained soil with high frost-heave characteristic should not be as the subgrade. The effective measure to prevent the rain percolated through the subgrade is important. And the filling of subgrade should be constructed strictly according to the maximal degree of compaction and keep the best water content. The settlement of subgrade is less than 15mm, the water content is also less than the prime frost-heave water content and the frost-heave force is very small. Thus, the construction technique subgrade is feasible.

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Experimental Study on Compaction and Strength Characteristic of Wetland Fine Grained Soil

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.336 ◽

2012 ◽

Vol 256-259 ◽

pp. 336-339

Author(s):

Hong Xia Yang

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Soil Moisture Content ◽

Optimum Moisture Content ◽

Dry Density ◽

High Moisture ◽

Compacted Soil ◽

Fine Grained ◽

Fine Grained Soil ◽

Work Effect

Through indoor the compaction test and unconfined compressive strength of compacted soil samples and CBR strength test, analyzes compaction characteristics of wetland fine grained soil and the change rule of compacted strength with compaction work and moisture content.The results show that under the same compaction work effect, when the soil moisture content is less than optimum moisture content,along with the increase of moisture content, dry density increases, when the soil moisture content is greater than the optimum moisture content, along with the increase of moisture content, dry density decreases and to a larger extent.When the compaction work is bigger, the soil dry density is bigger, the compaction strength is higher and the optimum moisture content is smaller.Strength decreases when under high moisture content condition, CBR value is relatively stable in the wet side of optimum moisture content.

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Dielectric permittivity of fine-grained fractions of soil samples from eastern Spain at 200 MHz

Geophysics ◽

10.1190/1.3294859 ◽

2010 ◽

Vol 75 (1) ◽

pp. J1-J9 ◽

Cited By ~ 9

Author(s):

Christina Salat ◽

Andreas Junge

Keyword(s):

Dielectric Permittivity ◽

Water Content ◽

Laboratory Data ◽

Clay Fraction ◽

Soil Samples ◽

Small Scale ◽

Carbonate Content ◽

Dry Density ◽

High Attenuation ◽

Fine Grained

To provide a database for interpreting GPR field data by means of small-scale laboratory studies, we have determined the real and imaginary parts of the dielectric permittivity of fine-grained fractions of soil samples from eastern Spain in the laboratory. We use the parallel-plate method in combination with an impedance analyzer and focus on the frequency of [Formula: see text]. The measurements are compared to physical properties such as volumetric water content, dry density, clay fraction, and carbonate content. The results show the well-known increase in dielectric permittivity with increasing water content, as presented in the literature; however, our values are systematically higher. This deviation may be caused by the exceptionally high carbonate content of the samples. We establish a basic relationship between dielectric permittivity and water content that is characteristic for soils in the research area. In addition to the dominating influence of water on permittivity, we find a correlation with dry density as well, which is linear for dry samples. Finally, we calculate the attenuation coefficients and find high attenuation for samples with high clay fraction, even at low water contents. A 1D model of the permittivity distribution is constructed from borehole data (water content and layer thickness) coincident with a GPR profile and from the laboratory data. The modeled GPR trace explains the observation and thus connects laboratory measurements to GPR data.

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