Method to determine height and water content of highway subgrade filled with fine grained soil materials

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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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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Review of Recent Developments and Understanding of Atterberg Limits Determinations

Geotechnics ◽

10.3390/geotechnics1010004 ◽

2021 ◽

Vol 1 (1) ◽

pp. 59-75

Author(s):

Brendan C. O’Kelly

Keyword(s):

Water Content ◽

Experimental Testing ◽

Soil Classification ◽

Liquid Limit ◽

Engineering Industry ◽

Plastic Limit ◽

Fine Grained ◽

Limit Test ◽

Fine Grained Soil ◽

Thread Rolling

Among the most commonly specified tests in the geotechnical engineering industry, the liquid limit and plastic limit tests are principally used for (i) deducing useful design parameter values from existing correlations with these consistency limits and (ii) for classifying fine-grained soils, typically employing the Casagrande-style plasticity chart. This updated state-of-the-art review paper gives a comprehensive presentation of salient latest research and understanding of soil consistency limits determinations/measurement, elaborating concisely on the many standardized and proposed experimental testing approaches, their various fundamental aspects and possibly pitfalls, as well as some very recent alternative proposals for consistency limits determinations. Specific attention is given to fall cone testing methods advocated (but totally unsuitable) for plastic limit determination; that is, the water content at the plastic–brittle transition point, as defined using the hand rolling of threads method. A framework (utilizing strength-based fall cone-derived parameters) appropriate for correlating shear strength variation with water content over the conventional plastic range is presented. This paper then describes two new fine-grained soil classification system advancements (charts) that do not rely on the thread-rolling plastic limit test, known to have high operator variability, and concludes by discussing alternative and emerging proposals for consistency limits determinations and fine-grained soil classification.

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Effects of A Low-Carbon Emission Additive on Mechanical Properties of Fine-grained Soil under Freeze-Thaw Cycles

Journal of Cleaner Production ◽

10.1016/j.jclepro.2021.127157 ◽

2021 ◽

pp. 127157

Author(s):

Shervin Ahmadi ◽

Hasan Ghasemzadeh ◽

Foad Changizi

Keyword(s):

Mechanical Properties ◽

Carbon Emission ◽

Low Carbon ◽

Freeze Thaw ◽

Fine Grained ◽

Fine Grained Soil ◽

Low Carbon Emission

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Modeling the Compaction Characteristics of Fine-Grained Soils Blended with Tire-Derived Aggregates

Sustainability ◽

10.3390/su13147737 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7737

Author(s):

Amin Soltani ◽

Mahdieh Azimi ◽

Brendan C. O’Kelly

Keyword(s):

Energy Levels ◽

Model Development ◽

Dry Mass ◽

Unit Weight ◽

Power Functions ◽

Compaction Characteristics ◽

Practical Applications ◽

Fine Grained ◽

Practical Procedure ◽

Fine Grained Soil

This study aims at modeling the compaction characteristics of fine-grained soils blended with sand-sized (0.075–4.75 mm) recycled tire-derived aggregates (TDAs). Model development and calibration were performed using a large and diverse database of 100 soil–TDA compaction tests (with the TDA-to-soil dry mass ratio ≤ 30%) assembled from the literature. Following a comprehensive statistical analysis, it is demonstrated that the optimum moisture content (OMC) and maximum dry unit weight (MDUW) for soil–TDA blends (across different soil types, TDA particle sizes and compaction energy levels) can be expressed as universal power functions of the OMC and MDUW of the unamended soil, along with the soil to soil–TDA specific gravity ratio. Employing the Bland–Altman analysis, the 95% upper and lower (water content) agreement limits between the predicted and measured OMC values were, respectively, obtained as +1.09% and −1.23%, both of which can be considered negligible for practical applications. For the MDUW predictions, these limits were calculated as +0.67 and −0.71 kN/m3, which (like the OMC) can be deemed acceptable for prediction purposes. Having established the OMC and MDUW of the unamended fine-grained soil, the empirical models proposed in this study offer a practical procedure towards predicting the compaction characteristics of the soil–TDA blends without the hurdles of performing separate laboratory compaction tests, and thus can be employed in practice for preliminary design assessments and/or soil–TDA optimization studies.

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Assessment for Thermal Conductivity of Frozen Soil Based on Nonlinear Regression and Support Vector Regression Methods

Advances in Civil Engineering ◽

10.1155/2020/8898126 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Fu-Qing Cui ◽

Wei Zhang ◽

Zhi-Yun Liu ◽

Wei Wang ◽

Jian-bing Chen ◽

...

Keyword(s):

Thermal Conductivity ◽

Support Vector Regression ◽

Nonlinear Regression ◽

Prediction Accuracy ◽

Prediction Models ◽

Frozen Soil ◽

Support Vector ◽

Soil Thermal Conductivity ◽

Fine Grained ◽

Fine Grained Soil

The comprehensive understanding of the variation law of soil thermal conductivity is the prerequisite of design and construction of engineering applications in permafrost regions. Compared with the unfrozen soil, the specimen preparation and experimental procedures of frozen soil thermal conductivity testing are more complex and challengeable. In this work, considering for essentially multiphase and porous structural characteristic information reflection of unfrozen soil thermal conductivity, prediction models of frozen soil thermal conductivity using nonlinear regression and Support Vector Regression (SVR) methods have been developed. Thermal conductivity of multiple types of soil samples which are sampled from the Qinghai-Tibet Engineering Corridor (QTEC) are tested by the transient plane source (TPS) method. Correlations of thermal conductivity between unfrozen and frozen soil has been analyzed and recognized. Based on the measurement data of unfrozen soil thermal conductivity, the prediction models of frozen soil thermal conductivity for 7 typical soils in the QTEC are proposed. To further facilitate engineering applications, the prediction models of two soil categories (coarse and fine-grained soil) have also been proposed. The results demonstrate that, compared with nonideal prediction accuracy of using water content and dry density as the fitting parameter, the ternary fitting model has a higher thermal conductivity prediction accuracy for 7 types of frozen soils (more than 98% of the soil specimens’ relative error are within 20%). The SVR model can further improve the frozen soil thermal conductivity prediction accuracy and more than 98% of the soil specimens’ relative error are within 15%. For coarse and fine-grained soil categories, the above two models still have reliable prediction accuracy and determine coefficient (R2) ranges from 0.8 to 0.91, which validates the applicability for small sample soils. This study provides feasible prediction models for frozen soil thermal conductivity and guidelines of the thermal design and freeze-thaw damage prevention for engineering structures in cold regions.

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