scholarly journals Mechanical and Microscopic Properties of Graphite/Laterite Nanocomposites

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Yuhao Gao ◽  
Jianzhong Li ◽  
Yuxin Zhang ◽  
Xu Sun ◽  
Leiyong Yang
Keyword(s):  
Soil Layer ◽  
Strength Properties ◽  
Triaxial Tests ◽  
Dry Density ◽  
Strength Increase ◽  
Coarse Particles ◽  
Laterite Soil ◽  
Soil Particles ◽  
Graphite Nanoparticles ◽  
Penetration Tests

The effectiveness and improvement mechanism of graphite nanoparticles (GN) in strength properties and microstructure characteristics of regional laterite were analysed in this study. Dry density was also taken into consideration, and the effects of graphite nanoparticle (GN) content and dry density were mainly addressed. Triaxial tests, consolidation tests, and penetration tests were used to analyse the effectiveness of different dry densities and graphite nanoparticle mass ratios on the properties of laterite; microscopic methods such as scanning electron microscopy (SEM) tests were used to analyse the improvement mechanism. The results show that the increase in dry density can make the laterite more compact. The large specific surface area and nanoeffects of the graphite nanoparticles (GN) induce the attraction between soil particles after mixing, both of which make the laterite’s shear strength; compression index and impermeability have been enhanced to varying degrees. The microscopic tests showed that, as the content of graphite nanoparticles (GN) continues to increase, when it exceeds 1.0%, the attraction between soil particles increases and coarse particles are formed, which leads to the increase of the pores of the soil. In addition, the graphite nanoparticles have a certain degree of lubricity, a high amount of graphite nanoparticles enters the laterite soil layer, increasing the distance and gap between the layers, making it easy to separate the coarse particles from the coarse particles, and the strength increase is reduced. However, it is still stronger than that of the plain laterite.

scholarly journals Soil and rock strength parameters of the Shiraidake Landslide, Japan

2001 ◽  
Vol 23 ◽  
Author(s):  
Robert Jelinek ◽  
Prem Prasad Paudel ◽  
Hiroshi Omura
Keyword(s):  
Rock Strength ◽  
Sedimentary Rocks ◽  
Strength Properties ◽  
Triaxial Tests ◽  
Dry Density ◽  
Compression Tests ◽  
Unconfined Compression ◽  
Strength Parameters ◽  
Consolidation Pressure ◽  
Early Tertiary

The Shiraidake area of northwest Kyushu has an extensive distribution of landslides. A series of undrained triaxial tests and unconfined compression tests were carried out to investigate the variation of strength properties in a selected borehole from the Shiraidake Landslide. It is a translational landslide (called the Hokusho-type in Japan) and is composed of the Early Tertiary and Quaternary sedimentary rocks that are prone to rapid weathering. Core rock samples and recompacted soil samples were used for the study. The results provided the fundamental characteristics of soil and rock under the triaxial and uniaxial tests, and indicated that the undrained behaviour of tested soils generally depends on the pre-shear consolidation pressure and dry density. In addition, the type of material used and the tests performed are important factors that influence the soil and rock strength.

scholarly journals Improvement Effect of Water-Based Organic Polymer on the Strength Properties of Fiber Glass Reinforced Sand

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 836 ◽  
Author(s):  
Jin Liu ◽  
Zezhuo Song ◽  
Yi Lu ◽  
Qiongya Wang ◽  
Fanxuan Kong ◽  
...  
Keyword(s):  
Stable State ◽  
Strength Properties ◽  
Fiber Content ◽  
Organic Polymer ◽  
Dry Density ◽  
Strength Increase ◽  
Polymer Content ◽  
Unconfined Compression ◽  
Fiber Glass ◽  
Water Based

The mechanical properties of sandy soil can be effectively improved by the incorporation of water-based polymer and glass fibers. In order to study the reinforcement effects of a type of water-based organic polymer and fiber glass on sand, three strength tests (unconfined compression test, direct shear test and tensile test) and scanning electron microscopy were carried out. A series of polymer content, fiber content and dry density were selected for the tests. The results revealed that the composite reinforcement of water-based organic polymer and fiber glass can improve the strength. With an increase in polymer content and fiber content, the unconfined compression strength, the cohesion, and the tensile strength increase. The internal friction angles maintain a relatively stable state. All three strength properties increase with an increase in dry density. The results can be considered as the reference for sand reinforced engineering.

Co-cooking nonwoods with hardwoods

TAPPI Journal ◽  
2014 ◽  
Vol 13 (6) ◽  
pp. 19-24
Author(s):  
TROY RUNGE ◽  
CHUNHUI ZHANG
Keyword(s):  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Paper Industry ◽  
Pulp And Paper Industry ◽  
Strength Properties ◽  
Agricultural Residues ◽  
Kraft Pulping ◽  
Pulp And Paper ◽  
Strength Increase ◽  
Xylan Content

Agricultural residues and energy crops are promising resources that can be utilized in the pulp and paper industry. This study examines the potential of co-cooking nonwood materials with hardwoods as means to incorporate nonwood material into a paper furnish. Specifically, miscanthus, switchgrass, and corn stover were substituted for poplar hardwood chips in the amounts of 10 wt %, 20 wt %, and 30 wt %, and the blends were subjected to kraft pulping experiments. The pulps were then bleached with an OD(EP)D sequence and then refined and formed into handsheets to characterize their physical properties. Surprisingly, all three co-cooked pulps showed improved strength properties (up to 35%). Sugar measurement of the pulps by high-performance liquid chromatography suggested that the strength increase correlated with enriched xylan content.

scholarly journals Research of the Behavior of Clay Materials with Double Porosity

2021 ◽  
Vol 13 (6) ◽  
pp. 3219
Author(s):  
Hynek Lahuta ◽  
Luis Andrade Pais
Keyword(s):  
Double Porosity ◽  
Strength Properties ◽  
Triaxial Tests ◽  
Building Structures ◽  
Foundation Soil ◽  
Problematic Use ◽  
The North ◽  
Static Liquefaction ◽  
Confinement Stress ◽  
Clay Materials

This contribution presents results from a series of compression and undrained triaxial tests to study the mechanical behavior of dump clay from the north of Bohemia. The use of these materials as a foundation for construction can’t be achieved without the adoption of some precautions. This comes from embankment, formed by digging the ground (altered claystone), up to the level of coal mining which is in a sub horizontal stratigraphic layer. A potential static liquefaction behavior was observed in undrained tests for high confinement stress. A structural collapse was noticed with the results obtained in the triaxial test. This collapse is characterized by an unexpected large decrease in deviator and mean effective stress. The soils formed have strength properties that are potentially dangerous. These concepts can improve the use of these kinds of soils in geotechnical engineering work. It continues and expands the results obtained in previous research, especially the future problematic use of these materials as the foundation soil for line or building structures.

scholarly journals Evaluation of Migration of Cesium-137 Adsorbed on Fine Soil Particles through Natural Aerated Soil Layer

1991 ◽  
Vol 28 (3) ◽  
pp. 248-254 ◽  
Author(s):  
Hiromichi OGAWA ◽  
Shinichi TAKEBE ◽  
Tadatoshi YAMAMOTO
Keyword(s):  
Soil Layer ◽  
Soil Particles ◽  
Fine Soil ◽  
Cesium 137

scholarly journals Evaluation of Strength Properties of Subgrade Materials Stabilized with Bio-Enzyme

2020 ◽  
Vol 5 (5) ◽  
pp. 607-610
Author(s):  
Bamidele S. Raheem ◽  
G. F. Oladiran ◽  
D. A. Oke ◽  
S. A. Musa
Keyword(s):  
Laboratory Experiments ◽  
Strength Properties ◽  
Dry Density ◽  
Sand Sample ◽  
Stabilizing Agent ◽  
Filling Materials ◽  
Base Materials ◽  
Long Term Effect ◽  
Enzyme Dosage

In the recent studies many chemical have been emerged and used as stabilizing agent. One of such chemical (Bio-enzyme) was used in this study as a stabilizing agent. Bio-enzyme is prepared locally from fermented vegetable and fruits waste. These products are natural, nontoxic, non-corrosive, nonflammable liquid and environmentally harmless. In this research, Bio-enzyme was prepared and used in varying proportion to stabilize laterite samples collected from different locations. Detailed laboratory experiments (Classification tests and CBR) were conducted to evaluate the effects of Bio-enzyme at varying dosage after 24 hours of curing of specimens. The percentage passing through sieve No. 200(75 micron) was less than 35%., according to ASHTO and clause 6201 of Federal Ministry of Works and Housing (F.M.W & H) Specification Requirements, sample A is (A-2-5), sample B is (A-2-4) while sample C is classified as A-2-6 and they are silty or clayed gravel and sand. Sample A is a good subgrade, subbase or base materials based on highest CBR values (at 20% bio-enzyme dosage, Sample A (102.50%) and sample B (69.40%) & at 10% sample C (33.2%). Sample B can also be used as subgrade or subbase materials where light traffic is considered and sample C is suitable as filling materials as evident in their CBR value. It has been observed that Bio-enzyme treated soil shows significant improvement in terms of the dry density and CBR value. Presence of Bio-enzyme in the soil samples led to increase in the C.B.R by 10-20% as compared to the control). However, it is recommended that assumption should not be made that Bio-enzyme is considered suitable for all type of soil and long term effect of it should also be examined.

scholarly journals Grazing and Cultivated Grasslands Cause Different Spatial Redistributions of Soil Particles

2019 ◽  
Vol 16 (15) ◽  
pp. 2639 ◽  
Author(s):  
Jinsheng Li ◽  
Jianying Shang ◽  
Ding Huang ◽  
Shiming Tang ◽  
Tianci Zhao ◽  
...  
Keyword(s):  
Soil Layer ◽  
Soil Health ◽  
Grazing Intensity ◽  
Health Condition ◽  
Soil Particle ◽  
Particle Sizes ◽  
Soil Layers ◽  
Soil Particles ◽  
Heavy Grazing ◽  
Grazing Intensities

The distribution of soil particle sizes is closely related to soil health condition. In this study, grasslands under different grazing intensities and different cultivation ages grasslands were selected to evaluate the dynamics of soil particle size redistribution in different soil layers. When the grazing intensity increased, the percentage of 2000~150-μm soil particles in the 0–10-cm soil layer decreased; 150~53-μm soil particles remained relatively stable among the grazing intensities—approximately 28.52%~35.39%. However, the percentage of less than 53-μm soil particles increased. In cultivated grasslands, the larger sizes (>53 μm) of soil particles increased and the smaller sizes (<53 μm) decreased significantly (p < 0.05) in the 0–10 cm-soil layer with increasing cultivation ages. The increase in small soil particles (<53 μm) in topsoil associated with grazing intensity increased the potential risk of further degradation by wind erosion. The increase in big soil particles (>53 μm) in topsoil associated with cultivation ages decreased the soil capacity of holding water and nutrient. Therefore, to maintain the sustainability of grassland uses, grazing grasslands need to avoid heavy grazing, and cultivated grasslands need to change current cultivation practices.

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.

Anisotropic shear strength of a residual soil of sandstone

2008 ◽  
Vol 45 (3) ◽  
pp. 367-376 ◽  
Author(s):  
Adriano Virgilio Damiani Bica ◽  
Luiz Antônio Bressani ◽  
Diego Vendramin ◽  
Flávia Burmeister Martins ◽  
Pedro Miguel Vaz Ferreira ◽  
...  
Keyword(s):  
Shear Strength ◽  
Effective Stress ◽  
Yield Surface ◽  
Triaxial Compression ◽  
Strength Properties ◽  
Triaxial Tests ◽  
Residual Soil ◽  
Compression Tests ◽  
Soil Stiffness ◽  
Particle Bonding

This paper discusses results of laboratory tests carried out with a residual soil originated from the weathering of eolian sandstone from southern Brazil. Parent rock features, like microfabric and particle bonding, are remarkably well preserved within this residual soil. Stiffness and shear strength properties were evaluated with consolidated drained (CID) and consolidated undrained (CIU) triaxial compression tests. Undisturbed specimens were tested with two different orientations between the specimen axis and bedding surfaces (i.e., parallel (δ = 0°) or perpendicular (δ = 90°)) to investigate the effect of anisotropy. When CID triaxial tests were performed with δ = 0°, the yield surface associated with the structure was much larger than when tests were performed with δ = 90°. Coincidently, CIU tests with δ = 0° showed peak shear strengths much greater than for δ = 90° at comparable test conditions. Once the peak shear strength was surpassed, CIU tests followed collapse-type effective stress paths not shown by corresponding tests with remolded specimens. A near coincidence was observed between the yield surface determined with CID tests and the envelope of collapse-type effective stress paths for δ = 0° and δ = 90°.

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