scholarly journals Application of an ionic stabilizer for reinforcing and ensuring frost resistance of clay soils

2020 ◽  
Vol 220 ◽  
pp. 01037
Author(s):  
V. A. Shorin ◽  
A. Y. Velsovskij ◽  
T R Akhmetov
Keyword(s):  
Water Saturation ◽  
Drainage System ◽  
Reinforced Soil ◽  
Appropriate Technology ◽  
Clay Soils ◽  
Local Clay ◽  
Insulating Layer ◽  
Clay Particles ◽  
Reinforced Soils ◽  
Structural Layer

This work is devoted to the study of applicability of the Underbold stabilizer for clay soils in the Vologda region, Russia. The influence of the stabilizer on maintaining the ultimate compressive strength of reinforced soils is shown. It depends on the content of clay particles (soil type) and can reach 30% if the appropriate technology (recommended by the manufacturer) is used. The use of the Underbold stabilizer according to our technology (treatment with a stabilizer - drying - reinforcing with cement) provides an increase in the strength of the reinforced soil after water saturation up to 2 or more times in comparison with samples without a stabilizer. It is shown that when designing a pavement using local clay soils reinforced by the Underbold stabilizer, it is necessary to make a water-insulating layer, and the necessary drainage system to improve the performance of the structural layer. It is noted that this stabilizer does not reduce the phenomenon of frost heaving.

Optimal water/cement ratios and strength characteristics of some local clay soils stabilized with cement

1985 ◽  
Vol 18 (2) ◽  
pp. 103-108 ◽  
Author(s):  
D. A. Aderibigbe ◽  
T. A. I. Akeju ◽  
C. O. Orangun
Keyword(s):  
Strength Characteristics ◽  
Clay Soils ◽  
Local Clay

Transport of formaldehyde in water unsaturated laboratory columns packed with quartz sand: Effect of colloid-sized clay particles.

2020 ◽  
Author(s):  
Theodosia V. Fountouli ◽  
Constantinos V. Chrysikopoulos
Keyword(s):  
Vadose Zone ◽  
Quartz Sand ◽  
Water Saturation ◽  
Packed Column ◽  
Interaction Energies ◽  
Unsaturated Porous Media ◽  
Great Abundance ◽  
Clay Particles ◽  
Colloid Particles ◽  
Colloid Retention

<p>Colloid-sized clay particles are in great abundance in the unsaturated or vadose zone and are capable of binding a variety of contaminants, which in turn either facilitate or hinder their migration in the subsurface. Also, FA has relatively strong affinity for kaolinite colloid particles (Fountouli et al., 2019). This study examines the effects of two representative colloid-sized clay particles (kaolinite, montmorillonite) on the transport of formaldehyde (FA) in unsaturated porous media. Transport experiments were performed in columns packed with quartz sand, under unsaturated conditions. The transport of FA was examined with and without the presence of suspended clay particles under various flow rates and various levels of saturation. DLVO interaction energies and the capillary potential energy associated with colloid retention at air-water and solid-water interfaces were calculated. The experimental results clearly suggested that the presence of suspended clay particles hindered the transport of FA in unsaturated packed columns. Moreover, as expected, it was shown that clay particle retention in the packed column increased with decreasing level of water saturation.</p><p> </p><p>Reference</p><p>Fountouli, T.V., C.V. Chrysikopoulos, and I.K. Tsanis, Effect of salinity on formaldehyde interaction with quartz sand and kaolinite colloid particles: batch and column experiments. Environmental Earth Sciences 78, 152, 2019.</p><p> </p>

Application of empirical performance criteria and limiting equilibrium principles in design of an earth wall reinforced with grouted rebar nails and cable anchors

1992 ◽  
Vol 29 (2) ◽  
pp. 299-308
Author(s):  
H. A. D. Kirsten ◽  
A. G. Dell
Keyword(s):  
Drainage System ◽  
Front Surface ◽  
Reinforced Soil ◽  
Performance Criteria ◽  
Short Term ◽  
Free Standing ◽  
Active Loading ◽  
Limiting Equilibrium ◽  
Loading Case

Soil nailing was employed to support the cut faces of a basement excavation for an apartment building. The layout detail and construction methods and procedures were similar to other successful applications of the technique with regard to depth of excavation, type of soil, width to height proportion of the reinforced monolith, spacing of nails, hole and reinforcement diameter, bench height, and drainage system. The design was based on limiting equilibrium principles with regard to two loading conditions, namely, active pressures and active pressures net of the cohesion of the retained mass. In the short term the monolith was free standing, and in the long term it was propped off the building in front of it. It was found for the short-term active loading case that the material in the lower sections of the front surface of the monolith and at the toe in the base was marginally overstressed. The factors of safety for the long-term active loading case exceeded unity by acceptable margins. The monolith was not overstressed for the active pressures net of the cohesion of the retained mass in the short or long term. The long-term stability of the monolith with regard to failure on deeply seated circular slip surfaces was also adequate. Key words : basement, excavation, reinforced, soil, nails, anchors, limiting, equilibrium.

scholarly journals EFFICIENCY OF STABILIZERS OF VARIOUS COMPOSITION FOR STRENGTHENING THE SOIL WITH A MINERAL BINDER

2020 ◽  
Vol 3 (1) ◽  
pp. 30-38 ◽  
Author(s):  
T. Dmitrieva ◽  
I. Markova ◽  
V. Strokova ◽  
A. Bezrodnykh ◽  
N. Kucyna
Keyword(s):  
New Technologies ◽  
Raw Materials ◽  
Lower Layer ◽  
Reinforced Soil ◽  
Clay Soils ◽  
Chemical Additives ◽  
The Road ◽  
Physicomechanical Characteristics ◽  
Inorganic Mineral ◽  
Mineral Binder

the depletion of natural deposits of traditional inert mineral raw materials (sand, gravel) used to create effective layers of the foundations of roads leads to the development and application of new technologies and alternative materials. One way to solve this problem is to use local raw materials. For the construction of the lower layer of the road basement local soils are often used. However, their use is associated with the development of a set of measures to increase their efficiency, such as stabilization (by the use of chemical additives) and/or strengthening (by the introduction of various types of binders). In this regard, the paper analyzes the physicomechanical characteristics of reinforced clay soils obtained by introduction of various types of stabilizing additives in the presence of an inorganic mineral binder of hydration hardening type - cement - taking into account the recommendations for the used additives. The object of research was the most common representative of clay soils of the Belgorod region – heavy dusty clay loam. As a result of the studies, the authors established the reasonability of the use of the additives in the presence of cement, the most effective compositions of the reinforced soil were identified, contributing to the improvement of its controlled physical and mechanical characteristics. In addition, the need for additional studies to adjust the recommended composition of reinforced soil was established.

scholarly journals Improvement in CBR value of soil reinforced with nonwoven geotextile sheets

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
S. Ramjiram Thakur ◽  
B. P. Naveen ◽  
J. P. Tegar
Keyword(s):  
Bearing Capacity ◽  
Asphalt Concrete ◽  
Clayey Soil ◽  
Vital Role ◽  
Reinforced Soil ◽  
Reinforced Soils ◽  
Cbr Test ◽  
Soil Settlement ◽  
Nonwoven Geotextile ◽  
Different Characteristics

AbstractGeosynthetics are human made material used to reinforce soils to improve the bearing capacity and permeability of the soil, reducing soil settlement. Geosynthetics application plays a vital role in the highways constructions with no additive layers, such as cement concrete, asphalt concrete, or in a subgrade layer that affects the bearing capacity of unbounded layers. This paper presents the geosynthetics as a tensional material that has been used for reinforcement of clayey soil. Laboratory California bearing ratio (CBR) test samples were prepared with clayey soils. Clayey soil containing unreinforced soil and reinforced soil. The sample comprised thermally bonded nonwoven geotextiles (NW) and superior needle-punched nonwoven geotextiles (SNW) with different characteristics (NW 8, 10, 21, 30 and SNW 14, 25, 62, 75) with three-layered, based on the sample materials to perform defined tests. These tests show that, bearing ratio of reinforced soils with thermally bonded nonwoven geotextiles increases.

scholarly journals Formation of the Energy Properties of the Surface of Clay Particles Modified by High Pressure

2021 ◽  
Vol 20 (1) ◽  
pp. 33-48
Author(s):  
M. V. Fyodorov ◽  
◽  
V. V. Seredin ◽  
I. V. Lunegov ◽  
◽  
...  
Keyword(s):  
High Pressure ◽  
Atomic Force Microscope ◽  
Mineral Composition ◽  
Adhesion Force ◽  
Clay Soils ◽  
Kaolin Clay ◽  
Adhesive Interaction ◽  
Clay Particles ◽  
Atomic Force ◽  
Silicon Cantilever

The article considers the issues of changing the energy activity of the surface of clay particles modified by pressure up to 800 MPa. The energy properties of the surface were evaluated by measuring the adhesion force between the surface of clay samples and the silicon cantilever of an atomic force microscope. It has been proved that when clay soils are modified by stress pressure, the adhesion force changes in different directions in clays with different mineral composition. So, in kaolin clay, with an increase in pressure from 25 to 800 MPa, the adhesion force increases, respectively, from 0.25 to 0.78 nN. In clays of montmorillonite composition, an increase in pressure to 150 MPa leads to an increase in the adhesive interaction, and a further increase in the load to 800 MPa leads to its decrease.

Influence of temperature on the hydrothermal clay soils' shear strength of the Nizhne-Koshelevsky and Verkhne-Pauzhetsky thermal fields.

2021 ◽  
Author(s):  
Ruslan Kuznetsov ◽  
Mikhail Chernov ◽  
Victoria Krupskaya ◽  
Ruslan Khamidov
Keyword(s):  
Internal Friction ◽  
Double Layer ◽  
Electric Double Layer ◽  
Geothermal Field ◽  
The Other ◽  
Clay Soils ◽  
Clayey Soils ◽  
Clay Particles ◽  
Angle Of Internal Friction ◽  
Thermal Fields

<p>Nizhne-Koshelevskoe and Verkhne-Pauzhetskoe thermal fields are located in the south of Kamchatka, the first - within the Koshelevsky volcanic massif, the second - on the territory of the Pauzhetsky geothermal field. The first horizon from the surface in these fields is formed by clayey soils, that have been formed as a result of hydrothermal alteration of volcanic rocks. And in the natural conditions clayey soils are at temperatures reaching 100 °C.</p><p>Samples of undisturbed clay soils were taken within the thermal fields. The samples are characterized by a density of 1.29 - 1.42 g/cm<sup>3</sup>, rather high values of the weight moisture (90-110%), and temperatures of 50 - 70 °C.</p><p>The samples are dominated by clay minerals: kaolinite and mixed-layer - kaolinite-smectite, their content is about 75%. The other 25% are microcline, cristobalite, anatase, gypsum, pyrite, marcasite, quartz and alunite.</p><p>For samples of undisturbed clay soils, direct shear tests were carried out at a temperature of 20 °C and at a temperatures of the samples close to their natural temperatures (50–70 °C). Thus, the values of cohesion and the angle of internal friction of the samples were determined.</p><p>The obtained results can be interfered as follows: as a result of an increase in the temperature of clayey soils, the thickness of electric double layer on the surface of clay particles decreases. On the one hand, it leads to a decrease of cohesion value between the clay particles and the beginning of shear deformations at lower vertical loads. On the other hand, a smaller thickness of electric double layer brings particles closer to each other, which is the reason for an increasing angle of internal friction and shear resistance at higher vertical loads.</p>

scholarly journals Determination of wind erosion intensity on heavy clay soils

2010 ◽  
Vol 58 (2) ◽  
pp. 155-160
Author(s):  
Jana Kozlovsky Dufková ◽  
Vladan Jareš ◽  
Petr Húsek
Keyword(s):  
Soil Loss ◽  
Wind Erosion ◽  
Clay Soils ◽  
Soil Erodibility ◽  
Clay Particles ◽  
Heavy Clay ◽  
Deep Soils ◽  
Soil Losses ◽  
Erosion Intensity

Wind erosion, common problem of light-textured soils, was determined on heavy clay soils in the foothills of Bílé Karpaty Mountains, Czech Republic. Soil erodibility by wind was determined from the Map of potential erodibility of soil by wind and from the calculation of potential and real soil loss by wind. All the determinations show underestimation of soil erodibility by wind on heavy clay soils, because methods that are used for this are based above all on the assessment of clay particles content and the presumption the more clay particles soil contains, the less vulnerable to wind erosion is. The potential erodibility of soil by wind is 0,09 t . ha−1 per year. The determined value does not exceed the tolerable soil loss limit 10 t . ha−1 per year for deep soils. The real average erodibility of soil by wind has the highest value 1,47 g . m−2 on November 30th, 2008. Other soil losses that do not exceed the tolerable soil loss limit 1,4 g . m−2, were determined on March 18th and 28th, 2008. Big difficulties come with the assessment of the erodibility of heavy clay soils in the areas, where soil erosion ve­ri­fia­bly exists, but it is not assessable by objective calculating methods. Evident necessity of new know­ledge concerning the determination of wind erosion intensity follows from the results.

scholarly journals Estimativas dos Riscos de Chuvas Extremas nas Capitais do Nordeste do Brasil (Estimates of the Risks of Extreme Rainfall in Capitals of Northeast Brazil)

2016 ◽  
Vol 9 (2) ◽  
pp. 430 ◽  
Author(s):  
Francisco De Assis Salviano de Sousa ◽  
Valmir Rocha Vieira ◽  
Vicente de Paulo R. da Silva ◽  
Valneli Silva Melo ◽  
Roni Walter De Souza Guedes
Keyword(s):  
Water Saturation ◽  
Drainage System ◽  
Extreme Rainfall ◽  
Poor Quality ◽  
Water Levels ◽  
Unequal Distribution ◽  
Distribution Of Wealth ◽  
Rain Events ◽  
Unequal Distribution Of Wealth ◽  
Brazilian Northeast

O objetivo deste estudo foi estimar os riscos de chuvas extremas nas nove capitais do Nordeste brasileiro no período de 19910 a 2012. Devido chuvas extremas e ao mau uso do solo, os desastres naturais mais comuns nessas capitais são as inundações, os deslizamentos e os desabamentos. Os desabamentos são consequências da ineficiência do sistema de drenagem, da remoção indiscriminada da cobertura vegetal e do aumento da saturação de água no solo, que reduz sua resistência e provoca sua ruptura. Também, os desmoronamentos devem-se ao mau uso do solo, má distribuição de renda, falta de moradia digna e má qualidade da educação pública. As inundações são acumulações de lâminas de água que podem invadir o interior das edificações e causar transtornos para a mobilidade urbana de pedestres e veículos. Esses eventos dependem de medidas estruturais e não estruturais e não prescindem da boa educação dos habitantes urbanos.  O ajuste dos eventos extremos de chuvas à função distribuição de probabilidade de Gumbel possibilitou as estimativas dos riscos para uma específica magnitude de chuva.      ABSTRACT   The objective of this study was to estimate the risks of extreme rainfall in the nine capitals of the Brazilian Northeast in the period 19910-2012. Due to extreme rainfall and bad land use, the most common natural disasters in these capitals are floods, mudslides and landslides. Landslides are consequences of the inefficiency of the drainage system, the indiscriminate removal of the vegetation and increasing water saturation in the soil reduces its strength and causes rupture. Also, landslides are due to misuse of land, unequal distribution of wealth, lack of decent housing and poor quality of public education. Floods are accumulations of the water levels that can invade the interior of buildings and cause inconvenience to urban mobility of pedestrians and vehicles. These events depend on structural and non-structural measures and of the good education of urban dwellers. After the fit of extreme rain events the Gumbel probability distribution function can be possible to estimate the risks for a specific magnitude of rain. Keywords: Extreme rains, mudslides, landslides and floods   

scholarly journals Evaluation of Compression Behaviors of Marine Clay Reinforced with Waste Shredded Tires

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Weijuan Geng ◽  
Hao Liu ◽  
Jie Yin ◽  
Yongwei Du ◽  
Daniel Kumah
Keyword(s):  
Regression Line ◽  
Soft Clay ◽  
Reinforced Soil ◽  
Content Increase ◽  
Compression Index ◽  
Compression Tests ◽  
Marine Clay ◽  
Compression Behavior ◽  
Clay Particles ◽  
The Difference

This study evaluates the compression behaviors of a soft marine clay reinforced with waste shredded tire (WST) at different sizes (<0.5 mm, 0.5–2.0 mm, and 2.0–4.0 mm) and contents (15%, 35%, and 50%). Results from compression tests indicate that the compression index (Cc) of WST-reinforced soft clay decreases with increasing WST shred size and content. The swelling index (Cs) increases as the WST shred size and content increase. The difference in compression curves becomes more significant for composite reinforced at large shred size. The void indexes of WST-reinforced Lianyungang clay can be well normalized regardless of WST shred size and content by a regression line. The WST dominates the compression behavior of the WST-clay composite, as the WST would be compressed prior to the clay particles. The results in this study provide an optimum WST content at 50% with shred size of 2.0–4.0 mm for reinforcing the Lianyungang marine clay for achieving higher compressibility, contributing to the input database of machine learning for WST-reinforced soil.

Sign in / Sign up

Export Citation Format

Share Document