Journal articles: 'Soils Thixotropy'

1

Voznesensky, Eugene A., Vladimir Y. Kalachev, Victor T. Trofimov, and Victoria V. Kostomarova. "Dynamic instability of seasonally thawing silty soils." Canadian Geotechnical Journal 31, no. 3 (June 1, 1994): 454–62. http://dx.doi.org/10.1139/t94-053.

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The peculiarities of the dynamic behaviour of silty soils in laboratory experiments that simulate their interaction with gas mining equipment are analyzed. These seasonally thawing soils appear to be very sensitive to dynamic loading and sometimes even liquefaction. Several peculiarities of their dynamic behaviour include: (i) their special sensitivity to very definite and narrow vibration frequency ranges, which vary with grain size and moisture content, and result from the resonant effects in the soil; (ii) the redistribution of pore water during the vibration and subsequent regain; (iii) the thixotropic recovery of the soil after vibration, resulting in the regain of its strength over initial levels, water content and density being constant. Both dilatant and thixotropic effects take place in such soils during dynamic loading, distinguishing them from both clean sands and clayey soils. On the basis of the peculiarities of dynamic behaviour discussed, the authors consider such soils as dilatantly thixotropic dispersed systems. Key words : dynamic properties, soils, thixotropy, liquefaction, resonance, silts.

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Abu-Farsakh, Murad, Firouz Rosti, and Ahmad Souri. "Evaluating pile installation and subsequent thixotropic and consolidation effects on setup by numerical simulation for full-scale pile load tests." Canadian Geotechnical Journal 52, no. 11 (November 2015): 1734–46. http://dx.doi.org/10.1139/cgj-2014-0470.

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During pile installation, stresses and void ratios in the surrounding soils change significantly, creating large displacements, large strains, soil disturbance, and development of excess pore-water pressures. The surrounding disturbed soil tends to regain its strength with time due to both consolidation and thixotropic effects. In this paper, the pile installation process and subsequent consolidation, thixotropy, and load tests conducted at different times after end of driving (EOD) were modeled for test piles at the Bayou Laccassine Bridge site, Louisiana. In the finite element (FE) model, the pile was considered as an elastic material and the anisotropic modified Cam-clay model (AMCCM) was used to describe the behavior of the surrounding clayey soils. Pile installation was modeled by applying prescribed radial and vertical displacements on the nodes at the soil–pile interface (volumetric cavity expansion), followed by vertical deformation to activate the soil–pile interface friction and simulate static load tests. The thixotropic effect was incorporated by applying a time-dependent reduction parameter, β, which affects both interface friction and material properties. Results from the FE numerical simulation include the development of excess pore-water pressure during pile installation and its dissipation with time, the increase in effective lateral stress at the pile–soil interface, changes in stress state of the surrounding soil, and setup attributed to both the soil consolidation and thixotropy at different times. FE results are compared with measured values obtained from full-scale instrumented pile load tests, which show good agreement between measured and FE-predicted results.

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Kamil, Ahmed Shakir, and Ala Nasir Aljorany. "Thixotropic Hardening of Fao Clay." Journal of Engineering 25, no. 5 (May 1, 2019): 68–78. http://dx.doi.org/10.31026/j.eng.2019.05.05.

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Fao region is characterized by weak soft silty clay to clayey silt thick layer which extends to a depth of about 20 m. The construction of some structures on such soils may needs piles. During the installation of driven piles, the soil geotechnical properties are exposed to significant changes result due to shearing under large shear strains. These changes significantly decrease the shear strength of the virgin soil due to the destruction of soil structure caused by remolding. The degradation of shear strength is usually followed by strength regaining which is called “Thixotropy”. In this study, the thixotropic effect on Fao clay was investigated. Many disturbed and undisturbed soil samples were brought from Fao region. Some of the soil samples were thoroughly remolded in the laboratory in its natural water content and molded as direct shear specimens. More than 180 specimens were prepared and tested over 36 weeks in order to accurately assess the percentage of strength regaining with time passing. The results show that soil remolding causes about a 45 % reduction in shear strength in comparing with the shear strength of the intact soil. This reduced percent in shear strength was almost fully regained after 25 weeks due to thixotropic effect.

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SANO, Hiroaki, Yoshinori DEMURA, Mikio YAMADA, and Kazuo ICHIMIYA. "EFFECT OF MONTMORILLONITE CONTENT ON THIXOTROPY OF COMPACTED SOILS." Doboku Gakkai Ronbunshuu C 62, no. 2 (2006): 305–10. http://dx.doi.org/10.2208/jscejc.62.305.

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Cui, Chun Yi, and Shou Long Chen. "Coupled Computational Analysis of Piled-Raft System on Saturated Rheologic Geomaterial Foundation." Advanced Materials Research 187 (February 2011): 631–36. http://dx.doi.org/10.4028/www.scientific.net/amr.187.631.

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It is well-known that soils may display strong nonlinear and inelastic characteristics. Furthermore, the viscosity or rheology of soft clays cannot be usually overlooked in the design of major structures founded on soft ground. Especially, rheologic deformation of soils may get considerable under high stress level. In fact, the saturated soft ground usually displays low strength, sensitive thixotropy, and high compressibility. In this paper, the soil deformation on interaction behaviour of piled rafts and soil foundation by using a fully coupled finite-element method of consolidation in which an elasto-viscoplastic model is incorporated. Through numerical computations, it is demonstrated that the coupled creep-consolidation analysis can give a more rational evaluation of overall performance of interaction of piled raft and soils and conventional analyses which overlooks time-dependency of soil deformation may give rise of inaccuracy in engineering evaluation and design of structures.

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Zakrevskaya, L. V., K. A. Nikolaeva, A. I. Gandelsman, and P. A. Orekhov. "Soil bases modified with lime waste and polycarboxylates." Journal of Physics: Conference Series 2124, no. 1 (November 1, 2021): 012023. http://dx.doi.org/10.1088/1742-6596/2124/1/012023.

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Abstract Increasing the volume of road construction is one of the priority areas of infrastructure development in any country. When building roads, it is preferable to use local materials to reduce the cost of their transportation, therefore, it is advisable to build the roadbed on local soils. It is worth noting that clay water-saturated soils are the most common, which complicates the construction of the road due to some features of this type of soil. The object of the study is a water-saturated clay with the following characteristics: natural humidity from 25.3 % to 28.1% by weight, optimal humidity from 11.8 % to 16.7% by weight, the number of plasticity from 0.118 to 0.153. Clay soils have a number of features: waterlogged soils are difficult to compact and develop, it is quite problematic to dry them, and thixotropy is also characteristic of clay soils. In this regard, it is most advisable to use the method of complex mineral binders to optimize their physical and mechanical properties. In the course of laboratory studies, compositions of soil compositions with the addition of lime waste and superplasticizer P-17 were developed. The dependence of the strength on the consumption of mineral binders and surfactants is established: the maximum compressive strength of the soil being fixed is achieved at a lime content of 25 wt.% and at a P-17 content in the range of 0.10-0.5 wt.%.

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Eyo, Eyo, Samuel Abbey, Jonathan Oti, Samson Ng’ambi, Eshmaiel Ganjian, and Eoin Coakley. "Microstructure and Physical-Mechanical Characteristics of Treated Kaolin-Bentonite Mixture for Application in Compacted Liner Systems." Sustainability 13, no. 4 (February 3, 2021): 1617. http://dx.doi.org/10.3390/su13041617.

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Treated bentonite-rich soils used as liner materials in landfills may provide an effective solution to the problems of increased void ratios upon swelling at reduced suction as well as desiccation cracking when suction is increased during desaturation. Accordingly, this study provides an understanding of the evolution of void ratio of the mixed materials during swelling at three different suction levels upon saturation as well as the soil water retention (SWR) during desaturation. For the treatment process, low quantity of cement binder whose production leverages raw material resources with efficient dry-process kilns and the benefit of lower energy consumption were used. Results indicated increased mixed soils’ strength irrespective of increased fines content due to thixotropy. The mixed soils exhibited almost equal values of void ratios at different hydration stages, suggesting that slightly reduced expansion mostly affects the subsequent phases of moisture ingress at full saturation compared to the natural soils. Lower values of void ratio obtained at full saturation also suggests possible reduced infiltration of water into landfills. The observed increased moisture retention within the osmotic suction zone and a decrease in the same as the fines content increased in the mixed soils can aid contaminant encapsulation while also reducing desiccation cracking. The findings of this research are intended to serve as a benchmark for further studies using other sustainable materials for treatment of mixed soils.

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Sun, Benhua, Paul G. Dennis, Kevin K. Newsham, David W. Hopkins, and Paul D. Hallett. "Gelifluction and Thixotropy of Maritime Antarctic Soils: Small-Scale Measurements with a Rotational Rheometer." Permafrost and Periglacial Processes 28, no. 1 (February 2, 2016): 314–21. http://dx.doi.org/10.1002/ppp.1886.

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9

Shao, Peng, Yu Yang Liu, Li Fen Zhou, and Yu Qi Wu. "Progress in Research on Explosion Induced Thixotropy of Concrete." Materials Science Forum 675-677 (February 2011): 643–46. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.643.

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Thixotropy is an important property possessed by fresh concrete of changing from gel to liquid under shearing stress and returning to the original state when at rest. The thixotropic process is usually described to be an isothermal and static (or quasi-static) gel-sol-gel transformation. Now the thixotropy of concrete subjected to explosive loads became a new subject in research of synchronous explosive lining technology, which offers an advanced trechless method for underground space construction in soil. Because the detonation of explosives is a short-duration process accompanying with high temperature and high pressure, thixotropic behavior of concrete is no longer as same as that of in general meaning. This review summarizes the recent progress in research on explosion induced thixotropy of concrete, including the thixotropic behavior, thixoforming, influence of thixotropic process on microstructure, macrostructure and mechanical performances of concrete and steel fibre reinforced concrete. Additional, some arguments and suggestions for the future research are presented.

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10

Tang, Bin, Biaohe Zhou, Liang Xie, Jianfeng Yin, Shengnan Zhao, and Zhibing Wang. "Strength Recovery Model of Clay during Thixotropy." Advances in Civil Engineering 2021 (February 2, 2021): 1–11. http://dx.doi.org/10.1155/2021/8825107.

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Thixotropy is a hot topic in the field of rheology of dispersed systems. Many researchers have proposed different models and hypotheses to explain the thixotropy of clay. In this paper, the strength recovery model of Zhanjiang Formation clay in the process of thixotropy is studied. Firstly, through unconfined compressive strength test, the influence of soil sensitivity, moisture content, and density on the strength growth of remolded soil was studied. The results show great influence of sensitivity, moisture content, and density on the thixotropic strength of the Zhanjiang Formation clay: the higher the sensitivity and the density, the stronger the thixotropy of soil; the higher the moisture content, the weaker the thixotropy of soil. Based on the test results, a strength recovery model of Zhanjiang Formation clay in the process of thixotropy was established. The model was verified by the validation test data and the data obtained from the existing literature. The results suggest that the model prediction is in good agreement with the verification test data and data from existing literature, which proves the confidence of the model in predicting the degree of strength recovery in the process of thixotropy of Zhanjiang Formation clay. The model provides basis for stability calculation of surrounding soil after construction disturbance of underground structures in this stratum.

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Sun, Zhiwen, Gangqiang Kong, Yang Zhou, Yang Shen, and Hanyu Xiao. "Thixotropy of a Transparent Clay Manufactured Using Carbopol to Simulate Marine Soil." Journal of Marine Science and Engineering 9, no. 7 (July 4, 2021): 738. http://dx.doi.org/10.3390/jmse9070738.

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A transparent clay manufactured using Carbopol® UltrezTM 10 (simplified as U10) was introduced, and its manufacturing processes were briefly described. Both relative transparency (RT) and modulation transfer function (MTF) methods were used to quantify the optical character variation via soil thickness. The transparency of this new transparent clay was analyzed and compared with four traditional transparent materials. The thixotropic properties of this synthetic transparent clay were measured in detail through the laboratory vane test. An exponential function was used to describe the thixotropy and sensitivity of the clay. The results showed that the new transparent clay has a relatively higher optical transparency than the majority of previous materials. Good-fitting results showed a similar development trend in thixotropy for the synthetic transparent clay and the natural ones. Furthermore, the sensitivity of the transparent clay was low to medium, which can simulate marine soil. With higher optical transparency than and similar thixotropy and sensitivity as natural clays, Carbopol® UltrezTM 10 shows great potential as a substitute for natural clay and is expected to be widely used in model tests.

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PANZHIN, A. A., and N. A. PANZHINA. "RESEARCH OF SHORT-PERIOD GEODYNAMICS OF ROCK ARRAY OF KACHKANAR MINING AND PROCESSING PLANT." News of the Tula state university. Sciences of Earth 2, no. 1 (2020): 318–29. http://dx.doi.org/10.46689/2218-5194-2020-2-1-318-329.

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This paper presents the methodology and results of the study of modern short-period geodynamics of the activity of the rock mass of the Kachkanar mining and processing plant (MPP). The determination of the parameters of geodynamic movements is carried out in the form of continuous monitoring by satellite geodesy complexes over a point system for several hours or days. The need to conduct studies on the organization of geodynamic monitoring in the quarries of the Kachkanarsky MPP is due to the peculiarities of the tectonic structure of the enclosing massif, in particular, the influence of a series of active tectonic disturbances crossing the quarries and tailings. The manifestations of geo-dynamic activity, which is realized in the form of trend and cyclical short-period shifts in tectonic disturbances, are associated with deformation processes occurring on the north-western side of the Main Quarry, as well as a breakthrough of the tailings dam. The role of cyclic geodynamic movements in the formation of the general stress-strain state of the area where quarries and tailings are located is shown. At the same time, these geodynamic movements lead to the formation of fatigue effects in structures and materials, “loosening” of the massif of rocks composing the instrument massif, a change in the strength properties of soils at the base of engineering structures, and the manifestation of the thixotropy effect.

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Chan, C. M., and H. Y. Yong. "Comparing the Thixotropic and Lightly Solidified Hardening Behavior of a Dredged Marine Clay." Engineering, Technology & Applied Science Research 4, no. 5 (October 11, 2014): 706–10. http://dx.doi.org/10.48084/etasr.494.

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When a soil is disturbed upon remolding, it may lose part or all of its strength. As time passes, the structural arrangement of the soil particles would be restored to a stable form and the soil would regain hardness under constant volume and water content. The process is known as “thixotropic hardening”. On another note, dredged marine soils of the fine-grained type can be reused as a backfill material instead of being disposed to the open sea. The rest period required for the relocated soil to regain strength and stiffness, i.e. thixotropic hardening, needs to be estimated precisely. For this purpose, a study on the phenomena of strength and stiffness gain by a dredged marine clay was carried out. The strength and stiffness improvement with time was measured using the vane shear and fall cone tests respectively. The clay was remolded at different water contents in multiples of the soil’s liquid limit (LL), namely 0.75LL, 1.00LL and 1.25LL, in order to evaluate the effect of initial water content on thixotropic hardening. A separate series of samples were prepared with light solidification using cement, to examine the possibilities of enhancing the soil’s improvement in a shorter rest period. The results showed the dredged marine clay can potentially be used as a backfill material for reclamation works, with lower initial water content and light solidification contributing to accelerated better performance

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14

Kul'chitskii, G. B. "Thixotropic soils of the tyumen region." Soil Mechanics and Foundation Engineering 27, no. 5 (September 1990): 195–97. http://dx.doi.org/10.1007/bf02309517.

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Jeong, Sueng Won, Jacques Locat, J. Kenneth Torrance, and Serge Leroueil. "Thixotropic and anti-thixotropic behaviors of fine-grained soils in various flocculated systems." Engineering Geology 196 (September 2015): 119–25. http://dx.doi.org/10.1016/j.enggeo.2015.07.014.

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Igwe, Charles A., and Karl Stahr. "Water-stable aggregates of flooded Inceptisols from south-eastern Nigeria in relation to mineralogy and chemical properties." Soil Research 42, no. 2 (2004): 171. http://dx.doi.org/10.1071/sr03041.

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Information on the influence of chemical and mineralogical properties on soil aggregate stability of field soils subjected to waterlogging at some time of the year is essential for better management of these soils. We studied water-stable aggregates (WSA) of various sizes for clay flocculation index, soil organic carbon, total elements, and mineralogy of the soil, and related these properties to aggregate stability. Five soil profiles sited on the floodplain of the River Niger were studied. The topsoils were dominated in all profiles except near the river by WSA�>�2.00�mm. Also the mean-weight diameter (MWD) of the topsoil followed the trend in WSA > 2.00 mm. Thixotropic age hardening appeared to be responsible for the rather high values of WSA > 2.00 and MWD in the topsoil. Soil organic carbon content associated significantly better with macroaggregates than microaggregates. The aggregating effects of the polyvalent cations manifested more on the microaggregates. The stabilising role of various forms of Fe, Al, and Mn oxides is believed to be as result of their large surface area, abundance, and the favourable environment for their formation. These polyvalent metals may have formed bridges between clay and organic matter in the formation of aggregates.

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Wang, Zhihua, Jinlong Ma, Hongmei Gao, Armin W. Stuedlein, Jian He, and Binghui Wang. "Unified thixotropic fluid model for soil liquefaction." Géotechnique 70, no. 10 (October 2020): 849–62. http://dx.doi.org/10.1680/jgeot.17.p.300.

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Romanov, S. V., and D. A. Romanov. "Procedure for impressing reinforced-concrete piles into leader holes using soil thixotropy." Soil Mechanics and Foundation Engineering 34, no. 1 (January 1997): 22–24. http://dx.doi.org/10.1007/bf02465085.

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Que, Xinzhe, Zhao Jin, Yixuan Hou, Yongchao Zhou, and Yiping Zhang. "Experimental Study on the Time-Dependent Characteristics of MLPS Transparent Soil Strength." Materials 15, no. 14 (July 18, 2022): 4990. http://dx.doi.org/10.3390/ma15144990.

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The time-dependent characteristics of transparent soil strength, composed of magnesium lithium phyllosilicate, is important for applying a thixotropic clay surrogate. The gas injection method was employed to obtain the strength, represented as cracking pressure, which was then correlated to variables including rest time, disturbance time, and recovery time. Three concentrations (3, 4, and 5%) were tested. The results show that the strength was directly proportional to the rest time, recovery time, and concentration while the disturbance time reversed. The calculated limit strengths for 3%, 4%, and 5% transparent soils were 3.831 kPa, 8.849 kPa, and 12.048 kPa, respectively. Experimental data also showed that the residual strength for higher concentration transparent soil was more significant than the lower ones. The elastic property immediately generated partial strength recovery after disturbance, while the viscosity property resulted in a slow recovery stage similar to the rest stage. The strength recovery rate was also sensitive to concentration. Furthermore, the strength with 3%, 4%, and 5% concentrations could regain limit values after sufficient recovery, which were calculated as 4.303 kPa, 8.255 kPa, and 14.884 kPa, respectively.

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20

Shao, Peng, Yong Zhang, Wen Ming Gao, and Yong Qiang Liu. "Investigation on Zonal Characteristics in Soil of Synchronous Explosion Forming." Key Engineering Materials 306-308 (March 2006): 1421–26. http://dx.doi.org/10.4028/www.scientific.net/kem.306-308.1421.

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Synchronous explosion forming, which takes advantage of the thixotropy of concrete or cement mortar and the condensability of soil under blasting concussion, is a newly developed method to construct underground cavities. In this paper, the mechanism of the new method is elucidated first, and then the zonal characteristics in soil are investigated emphatically. In order to accomplish comparative analysis, both synchronous explosion forming and conventional compression blasting experiments are conducted under same soil and explosive conditions. Experimental results indicate that the zonal characteristics in soil by synchronous explosion forming differ from that of by conventional compression blasting. When the new method is applied, formation and growth of cracks in soil during blasting is restrained, and the crannied region, which is usually produced in conventional compression blasting can be substituted by a soil- cement mortar occlusive region. Additional, the compaction range in soil is large when the new method is used. The zonal characteristics of synchronous explosion forming are more advantageous to the bearing capacity of soil and secular stability of cavity.

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Molope, M. B., I. C. Grieve, and E. R. Page. "Thixotropic Changes in the Stability of Molded Soil Aggregates." Soil Science Society of America Journal 49, no. 4 (July 1985): 979–83. http://dx.doi.org/10.2136/sssaj1985.03615995004900040037x.

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Shao, Peng, Dong Quan Wang, Chun Rong Liu, and Yu Xiao Zhu. "Experimental Study on Forming Underground Space in Soil Using Explosive Lining Method." Key Engineering Materials 353-358 (September 2007): 1121–24. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.1121.

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Explosive lining is a new method to construct underground space in soil. By making the most of compressibility of soil and thixotropy of concrete under explosive loading, this method offers an efficient path to form a cavity and its concrete support layer synchronously. In order to investigate the forming effect, a series of contrastive laboratory tests, including explosive lining method and conventional explosive compaction method, were performed under same soil and explosive conditions. Results show that measured dynamic stress and displacement by explosive lining method are higher than that of by conventional explosive compaction method under same equivalent radius, and the range of compact region in soil is larger too. Similarly, the physical and mechanical performance indexes of soil, such as water content and cohesion are superior to that of by conventional explosive compaction. It is approved that an even thickness concrete support layer can be formed in one-shot forming process by explosive lining, and there is no evident cranny region in the soil around the cavity.

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Ruge, J. C., F. Molina-Gómez, and J. P. Rojas. "Thixotropic behaviour study of clayey soils from the lacustrine deposits of Bogotá high plateau." Journal of Physics: Conference Series 1386 (November 2019): 012050. http://dx.doi.org/10.1088/1742-6596/1386/1/012050.

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Lee, Minhyeong, Jooyoung Im, Gye-Chun Cho, Hee Hwan Ryu, and Ilhan Chang. "Interfacial Shearing Behavior along Xanthan Gum Biopolymer-Treated Sand and Solid Interfaces and Its Meaning in Geotechnical Engineering Aspects." Applied Sciences 11, no. 1 (December 25, 2020): 139. http://dx.doi.org/10.3390/app11010139.

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Recently, environment-friendly microbial biopolymer has been widely applied as a new construction material in geotechnical engineering practices including soil stabilization, slope protection, and ground injection. Biopolymer is known to exhibit substantial improvements in geotechnical properties, such as shear strength enhancement and hydraulic conductivity reduction, through the formation of direct ionic bonds with soil particles, especially clay particles. Moreover, the rheological characteristics (e.g., pseudoplasticity, shear-rate dependent thixotropy) of biopolymers render distinctive behaviors such as shear thinning and lubrication effect under a high strain condition, while recovering their viscosities and shear stiffnesses when they are at rest. To ensure the practical applicability of biopolymer-based soil treatment, it is important to understand the interfacial interaction (i.e., friction) between biopolymer-treated soil and adjoining structural members which can be constructed in a biopolymer-treated ground. Thus, in this paper, interfacial shearing behavior of biopolymer-treated soil along solid surfaces as well as internal shearing on biopolymer-soil matrix were explored via direct and interface shear test. Experimental results show a predominant effect of the soil moisture content on the interfacial shear behavior of biopolymer-treated soil which attributes to the rheology transition of biopolymer hydrogels. At low moisture content, condensed biopolymer biofilm mobilizes strong intergranular bonding, where the interfacial shear mainly depends on the physical condition along the surface including the asperity angle. In contrast, the biopolymer induced intergranular bonding weakens as moisture content increases, where most interfacial failures occur in biopolymer-treated soil itself, regardless of the interface condition. In short, this study provides an overall trend of the interfacial friction angle and adhesion variations of xanthan gum biopolymer-treated sand which could be referred when considering a subsequent structural member construction after a biopolymer-based ground improvement practice in field.

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Zhang, Bang Hua, and Hong Shui Tian. "Analyzing Seismic Destructive Effect to the Submarine Rock and Soil Layers According to Submarine Seismic Records." Applied Mechanics and Materials 166-169 (May 2012): 2494–506. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.2494.

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By means of survey and study, various submarine seismic records were identified in the marine facies strata from Sinian Period to Ordovician Period in Tancheng-Lujiang seismic fault zone and its vicinity. These submarine seismic records are divided into two classes. According to the mode of seismic action, every class of submarine seismic records is divided into three to four types. On the basis of classification, this paper studied and summarized seismic destructive effects to the submarine rock and soil layers and diagrammatized mechanism and process of seismic destructive effects. Seismic destructive effects to soft sedimentary soil strata mainly include seismic vibratory liquefaction, vibratory thixotropic effect, seismic fold deformation, sliding deformation, tensile deformation and combined action of shaking and weight. Seismic destructive effects to submarine soil strata of semi-consolidated to un-completely consolidated sediments mainly include syn-sedimentary fault effect, crack and smashing effect, filling effect of seismic crack, etc.

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Zhang, Xinlei, Zhanpeng Ji, Hongmei Gao, Zhihua Wang, and Wenwen Li. "Pseudo-Static Simplified Analysis Method of the Pile-Liquefiable Soil Interaction considering Rate-Dependent Characteristics." Shock and Vibration 2022 (May 9, 2022): 1–14. http://dx.doi.org/10.1155/2022/5915356.

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The lateral pressure generated by liquefied soil on pile is a critical parameter in the analysis of soil-pile interaction in liquefaction-susceptible sites. Previous studies have shown that liquefied sand behaves like a non-Newton fluid, and its effect on piles has rate-dependent properties. In this study, a simplified pseudo-static method for liquefiable soil-pile interaction analysis is proposed by treating the liquefied soil as a thixotropic fluid, which considers the rate-dependent behavior. The viscous shear force generated by the relative movement between the viscous fluid (whose viscosity coefficient varies with excess pore pressure and shear strain rate) and the pile was assumed to be the lateral load on the pile. The results from the simplified analysis show that the distribution of bending moment is in good agreement with experiments data. Besides, the effects of various parameters, including relative density, thickness ratio of nonliquefiable layer to liquefiable layer, and frequency of input ground motion, on the pile-soil rate-dependent interaction were discussed in detail.

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Pycia, Karolina, Ewa Szupnar-Krok, Małgorzata Szostek, Renata Pawlak, and Lesław Juszczak. "Effect of Soil Type and Application of Ecological Fertilizer Composed of Ash from Biomass Combustion on Selected Physicochemical, Thermal, and Rheological Properties of Potato Starch." Molecules 27, no. 13 (July 5, 2022): 4318. http://dx.doi.org/10.3390/molecules27134318.

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The aim of the study was to assess the effect of soil type and the application of fertilizer composed of ashes from biomass combustion to potatoes on selected physicochemical, rheological, and thermal properties of potato starches isolated by using the laboratory method. Potatoes were grown in Haplic Luvisol (HL) and Gleyic Chernozem (GC) soil and fertilized with different doses of biomass combustion ash (D1–D6) with different mineral contents. The thermodynamic characteristics of gelatinization and retrogradation were identified by DSC. The analyses of rheological properties included the determination of the gelatinization characteristics by using the RVA method, flow curves, and assessment of the viscoelastic properties of starch gels. It was found that the starches tested contained from 24.7 to 29.7 g/100 g d.m. amylose, and the clarity of 1% starch pastes ranged from 59% to 68%. The gelatinization characteristics that were determined showed statistically significant differences between the starches analyzed in terms of the tested factors. The value of maximum viscosity and final viscosity varied, respectively, in the range of 2017–2404 mPa·s and 2811–3112 mPa·s, respectively. The samples of the potato starches studied showed a non-Newtonian flow, shear thinning, and the phenomenon of thixotropy. After cooling, the starch gels showed different viscoelastic properties, all of which were weak gels (tan δ = G″/G′ > 0.1).

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Sun, Lunqing, Yuxuan Pan, Yongwei Wang, Keling Xiao, Jun Wang, Yiyang Zhao, and Yangxuan Liao. "The Effects of Multiple Parameters on Initial Apparent Viscosity and Rheological Behavior in a Liquid-Phase Paddy Field." Journal of the ASABE 65, no. 5 (2022): 1141–48. http://dx.doi.org/10.13031/ja.15178.

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HighlightsSoil rheological properties in the liquid phase under various clay contents, moisture contents, and settling times were investigated.A numerical model of the initial apparent viscosity was established and verified.The change in soil rheological behavior at different rotating speeds was analyzed.Abstract. It is particularly important to study the rheological properties and rheological behavior of liquid-phase paddy soil to improve the working efficiency of power machinery in paddy fields. In this research, a rotational rheometer was used to record the shear stress, shear rate, and apparent viscosity of the soil during the test. Additionally, a numerical model was established to explore the effects of soil clay content, moisture content, and settling time on soil rheological properties. Through single factor analysis, the contribution rate of each factor to the change in the initial apparent soil viscosity was ranked as follows: moisture content (X2) > soil clay content (X1) > settling time (X3). Subsequently, the variations in shear stress and apparent viscosity at different shear rates were explored. The changing trend of soil rheological behavior was mainly related to soil texture, in which silty loam was thixotropic and clay loam was gelatinous. The prediction models for the initial apparent viscosity were validated, and the results showed great agreement. The research evaluated and predicted the rheological behavior of liquid-phase paddy field soil and provides a reference for the design, development, and use of paddy field power machinery. Keywords: Apparent viscosity, Clay content, Moisture content, Rheology, Settling time, Shear stress.

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Liu, Pengfei, Mingyong Du, Peta Clode, Hualong Li, Jishan Liu, and Yee-Kwong Leong. "Surface Chemisty, Microstructure, and Rheology of Thixotropic 1-D Sepiolite Gels." Clays and Clay Minerals 68, no. 1 (February 2020): 9–22. http://dx.doi.org/10.1007/s42860-019-00050-z.

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Yan, Xin, Wei Zhan, Zhi Hu, Danqiang Xiao, Yiqiang Yu, and Jinchang Wang. "Field Study on Deformation and Stress Characteristics of Large Open Caisson during Excavation in Deep Marine Soft Clay." Advances in Civil Engineering 2021 (October 25, 2021): 1–11. http://dx.doi.org/10.1155/2021/7656068.

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Oujiang River North Estuary Bridge in Wenzhou is the world’s first double-deck suspension bridge under construction with three-tower and four-span. It is the first time to build large open caisson foundation in the deep marine soft clay in estuary with strong tide, extending the application scope of caisson. To study the deformation and stress characteristics of large open caisson during excavation and ensure the safety of anchorage excavation, a large number of sensors are arranged in the caisson. By analyzing the change of tip resistance, lateral soil pressure, and posture parameters during caisson excavation, the stress characteristics and deformation of caisson are described. The result shows the following. (1) Because of the thixotropy of soft clay, the reaction force of partition wall in deep soft soil area of caisson is similar to that of blade foot, and the reaction force of blade foot can be effectively reduced through the layering construction of caisson. (2) The height of caisson construction and the sand-bearing stratum will obviously affect the plane torsion angle of caisson. When the caisson enters the sand-bearing stratum, the lateral soil pressure increases significantly, which leads to the increase of the plane torsion angle. (3) The inclination and central deviation of caisson are sensitive to the caisson construction and stratum property. It can be found that the lateral soil pressure, plane torsion angle, inclination, and central deviation of caisson are sensitive to stratum property, and inhomogeneity of stratum easily leads to inclination of caisson. Based on the field monitoring data, the stress characteristics and geometric posture of caisson during sinking are studied, which provide technical guidance for scheme design and subsidence prediction analysis of caisson in deep marine soft clay. It can provide a good opportunity to study the behaviors of large caisson foundation constructed in deep marine soft clay and has great significance and reference value for construction optimization of anchorage structure.

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Panzhin, A. A., and A. A. Panzhina. "Analysis of geodynamic activity in rock mass at opencast mines and tailings ponds of the Kachkanar Mining and Processing Plant." Mining informational and analytical bulletin, no. 3-1 (March 20, 2020): 178–87. http://dx.doi.org/10.25018/0236-1493-2020-31-0-178-187.

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The article presents the procedure and findings of the research into the modern geodynamic activity of rock mass at the Kachkanar Mining and Processing Plant. The characteristics of the cyclic short-period movements are determined in the course of continuous monitoring by satellite geodesy facilities within a few hours or days. The geodynamic monitoring in opencast mines of Kachkanar MPP is conditioned by the specific tectonic structure of enclosing rock mass, in particular, by the impact of a set of the active tectonic faults intersecting opencast mines and tailings ponds. The amplitudes of displacements and straining are determined in horizontal plane, vertically and in three-dimensional space. The accuracy of geodetic data was analyzed using two independent methods. The Fourier analysis of space-and-time series of displacements determined prevailing frequencies of the cyclic short-period movements. The peak values in the periodograms fitted the period of the short-period strains. The role of the cyclic geodynamic movements in the formation of the general stress-strain behavior of rock mass in the area of opencast mines and tailings ponds of Kachkanar MPP, EVRAZ is illustrated. The geodynamic movements induce fatigue phenomena in structures and materials, loosening of adjacent rock mass of opencast mines, change in the strength properties of soil at the bottom of engineering structures and the thixotropy effect.

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Boffa, V., J. E. ten Elshof, and D. H. A. Blank. "Preparation of templated mesoporous silica membranes on macroporous α-alumina supports via direct coating of thixotropic polymeric sols." Microporous and Mesoporous Materials 100, no. 1-3 (March 2007): 173–82. http://dx.doi.org/10.1016/j.micromeso.2006.10.035.

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TATYANA S., ALYOSHINA, and PLATOV NIKOLAY A. "GEOECOLOGICAL ASSESSMENT OF CHANGES IN ROCK PROPERTIES UNDER THE INFLUENCE OF TECHNOGENIC FACTORS." Geology, Geography and Global Energy 81, no. 2 (2021): 153–56. http://dx.doi.org/10.21672/2077-6322-2021-81-2-153-156.

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Technogenic impact on the geological environment inevitably leads to a change in the properties of rocks. Engineering structures quite often directly interact with rocks, therefore, reliable determination of their properties is an urgent task in construction. From a practical point of view, knowledge of not only the physical and mechanical properties of rocks, but also their characteristics in contact with technogenic impact is of great interest. This determines the relevance of studying the characteristics of changes in the properties of rocks under the influence of technogenic factors. The aim of the work is to consider the issues of changing the properties of rocks under the influence of technogenic factors of the geological environment. Technogenic impact on the geological environment is classified according to various criteria, and is divided into global, zonal, regional and local categories. The authors rightly give preference to the following operating factors: pressure, fluctuations in the stress state, hydrogeological conditions, changes in the composition of groundwater, etc. Particular attention is paid to rock swelling, rock salinization and the influence of various microorganisms on rocks. In the article of the above authors, it is proposed to consider in detail the orohydrographic conditions of the studied geological environment, geomorphological conditions of the territory, geological structure, hydrogeological conditions (upstream, groundwater, interstratal waters), geo-dynamic conditions (all processes and phenomena expressed in a given territory), as well as to study the composition (mineral, granulometric, chemical), the state of rocks (moisture, density, porosity) and properties of rocks (strength, deformation and geological) - for a comprehensive assessment of the surrounding geological environment. Attention is also paid to the dynamic impact, i. e. the factors of liquefaction, thixotropy and other soil deformations are given.

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Rył, Anna, and Piotr Owczarz. "Influence of Injection Application on the Sol–Gel Phase Transition Conditions of Polysaccharide-Based Hydrogels." International Journal of Molecular Sciences 22, no. 24 (December 8, 2021): 13208. http://dx.doi.org/10.3390/ijms222413208.

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Polysaccharide matrices formed via thermoinduced sol–gel phase transition are promising systems used as drug carriers and minimally invasiveness scaffolds in tissue engineering. The strong shear field generated during injection may lead to changes in the conformation of polymer molecules and, consequently, affect the gelation conditions that have not been studied so far. Chitosan (CS) and hydroxypropyl cellulose (HPC) sols were injected through injection needles (14 G–25 G) or sheared directly in the rheometer measuring system. Then the sol–gel phase transition conditions were determined at 37 °C using rheometric, turbidimetric, and rheo-optical techniques. It was found that the use of low, respecting injection, shear rates accelerate the gelation, its increase extends the gelation time; applying the highest shear rates may significantly slow down (HPC) or accelerate gelation (CS) depending on thixotropic properties. From a practical point of view, the conducted research indicates that the use of thin needles without preliminary tests may lead to an extension of the gelation time and consequently the spilling of the polymeric carrier before gelation. Finally, an interpretation of the influence of an intensive shear field on the conformation of the molecules on a molecular scale was proposed.

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A. BORISOV, I. BABIJ, S. KYRYLIUK, and L. LUKASHENKO. "PLANNING OF EXPERIMENTAL RESEARCHES ON DETERMINATION OF PROTECTIVE SCREEN CHARACTERISTICS." Bridges and tunnels: Theory, Research, Practice, no. 12 (May 21, 2019): 4–9. http://dx.doi.org/10.15802/bttrp2017/167347.

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Purpose. The purpose of this work is to develop a research methodology, on the basis of which it is possible to perform the selection of the composition of the solution with the determination of the physicomechanical characteristics of both the thixotropic and hardened solution, as well as to determine the effect of the number of individual components on the properties of the mortar mixture and the protective screen based on it. Methodology. The research method is to use an adapted plan of experimental-statistical modeling to solve specific problems, namely when creating a reliable, inclined filtering screen inside the sand massif under conditions when technological parameters change. Technological research method: analytical and experimental. Findings. To solve the problems of analysis and optimization of the factor systems under study, the theory of mathematical modeling was used in the work. At the same time, experimental-statistical regression models are considered, which show how the indicator under study (y) changes as the relevant factors change. Originality. According to the results of the work, a technique has been obtained that allows, with a minimum amount of materials and experiments, to obtain the physicomechanical indicators of solutions and a protective soil-concrete screen based on them.

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Poitou, A., G. Racineux, and N. Burlion. "Identification and measurement of pastes rheological properties – effects of water dissociation." Water Science and Technology 36, no. 11 (December 1, 1997): 19–26. http://dx.doi.org/10.2166/wst.1997.0389.

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Sewage sludges exhibit in most cases rheological properties which do not allow us to classify them either as simple fluids or as solids. On one hand, they are not simple fluids because of their non-Newtonian, shear-thinning and time-dependent (thixotropic or rheopectic) behaviour and because of the possibility for some of them of showing a yield stress. On the other hand, they can hardly be considered as solids, mostly because of their high sensitivity to velocity and because they are practically very often pumped as if they were fluids. This intermediate state sometimes referred to as paste state is in fact very common and is extensively studied, from a manufacturing point of view in areas like ceramics, food or polymer processing and from a civil engineering point of view in soil mechanics for the determination of clay rheology. Many experimental tests have already been designed for their characterisation. The aim of this presentation is to compare some of them and try to make a synthesis between the engineering rheology and soil mechanics approaches. For this purpose we show experimental results on the same material with different rheometric devices: viz (i) a tube (or capillary) ROSAND rheometer, (ii) a triaxial soil mechanics cell, (iii) an oscillatory, stress driven, plane and plane STRESSTECH rheometer, and (iv) a specific squeezing device which has been designed here following an idea introduced by Laun for polymers. The triaxial cell and the plane and plane rheometers are similar in the sense that they are supposed to allow for an homogeneous state of stress and strain (or rate of strain). In contrast, the tube or squeezing test does not allow for a homogeneous mechanical state. This means that the first two tests enable a real measure of the constitutive relation but in limited conditions while the two others provide a way to identify rheological parameters in flow conditions which are close to the process conditions. The main originalities of this presentation are (i) the balanced point of view between the fluid and the solid mechanics approach and (ii) the method by which the contact properties of the paste is measured with the tube and the squeezing rheometer, giving evidence of a water migration inside the paste.

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Troshchynska, Yana, Roman Bleha, Andriy Synytsya, and Jiří Štětina. "Chemical Composition and Rheological Properties of Seed Mucilages of Various Yellow- and Brown-Seeded Flax (Linum usitatissimum L.) Cultivars." Polymers 14, no. 10 (May 17, 2022): 2040. http://dx.doi.org/10.3390/polym14102040.

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When seeds sown in the soil become wet, their hulls secrete viscous matter that can retain water and thus support germination. Flaxseed mucilage (FSM) is an example of such a material and is attractive for food, cosmetic, and pharmaceutical applications due to its suitable rheological properties. FSM consists mainly of two polysaccharides, namely, arabinoxylan and rhamnogalacturonan I, and it also contains some proteins, minerals, and phenolic compounds. The genotype and the year of the flax harvest can significantly affect the composition and functional properties of FSM. In this work, FSM samples were isolated from flax seeds of different cultivars and harvest years, and their structural and rheological properties were compared using statistical methods. The samples showed significant variability in composition and rheological properties depending on the cultivar and storage time. It was found that the ratio of two polysaccharide fractions and the contribution of less-prevalent proteins are important factors determining the rheological parameters of FSM, characterizing the shear-thinning, thixotropic, and dynamic viscoelastic behavior of this material in aqueous solutions. The yield strength and the hysteresis loop were found to be associated with the contribution of the pectin fraction, which included homogalacturonan and rhamnogalacturonan I. In contrast, the shear-thinning and especially the dynamic viscoelastic properties depended on the arabinoxylan content. Proteins also affected the viscoelastic properties and maintained the elastic component of FSM in the solution. The above structural and rheological characteristics should be taken into account when considering effective applications for this material.

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Seul, Cyprian. "Warunki geologiczno-inżynierskie na obszarze strefy krawędziowej Wzgórz Warszewskich." Annales Universitatis Mariae Curie-Sklodowska, sectio B – Geographia, Geologia, Mineralogia et Petrographia 70, no. 2 (July 7, 2016): 9. http://dx.doi.org/10.17951/b.2015.70.2.9.

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<p>Development trends of the modern city imply a reduction in the number of inhabitants in its centre, and thus the construction of dormitory suburbs on the outskirts of the city. One of the potential areas for the development ofSzczecinis its northern part, i.e. the so-called Warszewo Hills. This area has both latitudinal and meridional extents of about 8 km, and is characterized by complicated engineering-geological conditions. It lies at altitudes ranging from the sea level (OdraRiver) to 130.9 m a.s.l. (Wielecka Góra), and has very varied relief. Its landscape consists of hills and flat plateaux, which are cut by deep small valleys, some of them with streams (e.g. the Warszewiec stream). Geological structure is characterized by the occurrence of glacitectonically disturbed moraine deposits mixed with the Tertiary sands and clays. Taking into account geodynamic processes and their intensity, the wide edge zone of the Warszewo Hills can be divided into three main parts: plateau with the upper edge of slope (area of precipitation infiltration), slope, which is cut by small erosion valleys in places (area of surface water and groundwater flow), slope foot (area of water flow and accumulation of slope deposits). One of the most important tasks of the design-investment process is to take action in such a way as to interfere as little as possible in the natural environment and at the same time to achieve the intended purpose. Predominant occurrence of cohesive deposits in the described area (Oligocene scaled clay mixed with moraine disturbed material) results in a high susceptibility of ground to moisture changes. Strength parameters of stable slopes built of clays considerably decrease under the influence of increasing moisture and thixotropy phenomenon. Then landslide processes are triggered, as well as very slow, hardly noticeable in a short time, soil creep. The complicated arrangement of deposit layers results in spatial variability of groundwater level, and proper design of building foundation is difficult, even in the case of a small, detached house. Too much interference in the landform features (through macro-levelling, construction of streets and routes in the area with steep slopes), the decrease of water retention and increase of surface runoff contribute to an intensification of some geodynamic processes. </p>

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Ledevin, M., N. Arndt, A. Davaille, R. Ledevin, and A. Simionovici. "The rheological behaviour of fracture-filling cherts: example of Barite Valley dikes, Barberton Greenstone Belt, South Africa." Solid Earth 6, no. 1 (February 20, 2015): 253–69. http://dx.doi.org/10.5194/se-6-253-2015.

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Abstract. In the Barberton Greenstone Belt, South Africa, a 100–250 m thick complex of carbonaceous chert dikes marks the transition from the Mendon Formation to the Mapepe Formation (3260 Ma). The sub-vertical- to vertical position of the fractures, the abundance of highly shattered zones with poorly rotated angular fragments and common jigsaw fit, radial structures, and multiple injection features point to repetitive hydraulic fracturing that released overpressured fluids trapped within the shallow crust. The chemical and isotopic compositions of the chert favour a model whereby seawater-derived fluids circulated at low temperature (< 100–150 °C) within the shallow crust. From the microscopic structure of the chert, the injected material was a slurry of abundant clay-sized, rounded particles of silica, carbonaceous matter and minor clay minerals, all suspended in a siliceous colloidal solution. The dike geometry and characteristics of the slurry concur on that the chert was viscoelastic, and most probably thixotropic at the time of injection: the penetration of black chert into extremely fine fractures is evidence for low viscosity at the time of injection and the suspension of large country rock fragments in the chert matrix provides evidence of high viscosity soon thereafter. We explain the rheology by the particulate and colloidal structure of the slurry, and by the characteristic of silica suspensions to form cohesive 3-D networks through gelation. Our results provide valuable information about the compositions, physical characteristics and rheological properties of the fluids that circulated through Archean volcano-sedimentary sequences, which is an additional step to understand conditions on the floor of Archean oceans, the habitat of early life.

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Al-Rubaiee, Abdul-Kareem H., and Rand S. Al Salami. "Determination of the Sensitivity and Thixotropic Effects of Clay Soil for Selected Sites in Diwaniya City - Iraq." Journal of Southwest Jiaotong University 55, no. 2 (2020). http://dx.doi.org/10.35741/issn.0258-2724.55.2.58.

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This paper is conducted to determine the sensitivity and thixotropic effects of clay soil for selected sites in Diwaniya city which are: (Dawr Aldubbat, Al-Zawra square, 14 Ramadan square, Al'iiskan Alaqadim and Military square). The main aim of this investigation is to study the sensitivity and thixotropy of clay soil, and determination and classification of soils to (Insensitive), (slightly to very sensitive) and (slightly to extra quick)) relying on special test methods in sensitivity and thixotropic phenomena. The experimental tests that were done including geotechnical, chemical and mineralogical tests to natural soils and special tests were for the identification and classification of sensitivity of soils. The results of sensitivity of soils test displayed low to medium for all the types of the soils in the study area. The results of the thixotropic strength ratio test showed a small increase in thixotropic strength ratio values with time. The results of Atterberg limits test indicated that increasing the proportion of the clay causes an increase in the plasticity index of the soil. While the results of the liquidity index varied from 0.24 to 0.70, which reflects the low sensitivity of the clay soil in the study area.

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Tang, Bin, Liang Xie, Wei Wang, Biaohe Zhou, and Yanxia Gong. "Unconfined compressive strength and pore structure evolution law of structural clay after disturbance." Frontiers in Earth Science 10 (August 12, 2022). http://dx.doi.org/10.3389/feart.2022.932621.

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The clay in the Zhanjiang Formation has thixotropic properties, which has greatly influenced the foundation engineering in the Zhanjiang area. The evolution law of macroscopic strength and clay microstructure during thixotropy can be used to explain the practical engineering problems caused by thixotropy. For undisturbed and reconstituted soil curing for a different period, unconfined compressive strength test, scanning electron microscopy, and mercury injection porosimetry test were carried out to obtain the unconfined compressive strength and pore structure evolution law in the thixotropic process. The results indicate that the Zhanjiang Formation structural clay is very sensitive to disturbance and its unconfined compressive strength decreases from 180.29 to 11.73 kPa after the natural structure is completely destructed. After 300 d of curing, the unconfined compressive strength of clay increased from 11.73 to 53.43 kPa because of thixotropy, which increased by 3.55 times. The stacking flaky flocculation structure of the undisturbed soil is destructed by reconstituting, turning to flaky flocculation structure, and the large pores are homogenized, the small pores develop into medium pores, and there is a decrease in soil strength. In the process of thixotropy, the soil particles gradually coagulate and form an aggregates flocculation structure, and the strength of clay increases with the increase in the degree of cementation. Based on the results, the thixotropic pattern of clay was established and its thixotropic mechanism was explained.

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"Thixotropic soils of the Tyumen region." International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 29, no. 2 (March 1992): A86. http://dx.doi.org/10.1016/0148-9062(92)92237-7.

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Tuebue, J. C. Fopoussi, S. D. Basga, P. Tematio, and J. P. Nguetnkam. "Organisation of Soils along the Sides of Interfluves in the Western Highlands of Cameroon: Case Study of an Andosolic Toposequence on Trachyte in the Upper Part of the Southern Limb of Bambouto Mountains." Asian Journal of Soil Science and Plant Nutrition, October 12, 2019, 1–19. http://dx.doi.org/10.9734/ajsspn/2019/v5i130058.

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The acquisition of knowledge on soils tells how to use them sustainably. So, the organization of soils along the sides of interfluves in the western highlands of Cameroon was put into relief in order to understand their genesis, organization, and evolution. Field work and lab analysis helped to reach the focuses. These soils are thin, highly differentiated, with many local specificities. Their organization and their thickness vary from up to downhill. Vertically, they include: An isalteritic horizon; a yellow vague polyhedral horizon; a red distinct polyhedral horizon; a discontinuous breastplate with two facies; a porous vague crumby dark reddish brown horizon; and a strongly dark grey, porous, thixotropic and crumby superficial horizon. The pedon/alterite ratio is about 2/1, and the hardened level/alterite ratio is 1/4. The alteritic level represents about 1/3 of the whole soil profile. Microscopically, these soils lack plasmic separations. Plasmas are respectively isotic in the dark reddish brown and strongly dark grey horizons, clayey asepic in the yellow and red polyhedral horizons, cristic in the isalteritic horizon, cristic and locally isotic in the discontinuous breastplate. Gibbsite, halloysite, kaolinite and allophane are the main minerals; goethite, quartz, hematite and rutile are also present. Geochemically, aluminum is the main chemical component in the deepest horizons, while in those at the top of the soil profile, silicon and aluminum has quite similar concentrations. Others specificities include their low bulk density (0.6 to 0.9 gcm-3), the abundance of clayey particles at the bottom of the soil profile, sand and silt at its summit. Ferrallitic and andosolic characteristics coexist in the studied soils. This ambivalence makes them to be simply «andic ferallitic, desaturated, humic and strongly rejuvenated soils».

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"Microstructural changes associated with thixotropic phenomena in clay soils." International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 22, no. 1 (February 1985): A8. http://dx.doi.org/10.1016/0148-9062(85)92657-9.

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Bailey, J. K., T. Nagase, G. A. Pozarnsky, and M. L. Mecartney. "Vanadium Pentoxide Gels: Structural Development and Rheological Properties." MRS Proceedings 180 (1990). http://dx.doi.org/10.1557/proc-180-759.

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ABSTRACTCryogenic transmission electron Microscopy (cryo-TEM) and rheological characterization were conducted in order to understand structural development of vanadium pentoxide gels during processing. Sols were prepared by ion exchange from sodium metavanadate solutions. Cryo-TEM revealed that fine threads about 1.5nm wide initially form and grow into ribbons approximately 25nm wide and at least 1000nm long. The threads appear to self assemble into the ribbons. During this structural development, the dynamic viscosity increased. Upon steady shearing of the sols, the system exhibited thixotropy, i.e. the viscosity decreased with time under constant shear stress and subsequently rheopexy, the viscosity increased with time. Comparison of the structure before and after shearing indicated that during the rheological experiments aggregation of small particles or fragments was occurring.

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Alam, Md Kausar, Azmayeen Rafat Shahriar, Mohammad Shariful Islam, Naveel Islam, and Md Zoynul Abedin. "Experimental Investigation on the Strength and Deformation Aspects of Thixotropic Aging in Reconstituted Clays." Geotechnical and Geological Engineering, November 18, 2020. http://dx.doi.org/10.1007/s10706-020-01639-1.

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Journal articles on the topic 'Soils Thixotropy'

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