Analysis of strain anisotropy and hydroscopic property of clay and claystone

Ponomaryov, Andrey; Sychkina, E. N.

doi:10.1016/j.clay.2015.05.023

Cited by 7 publications

(5 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Claystone refers to a fine-grained clastic sedimentary rock resulting from the transformation of weakly consolidated clay under moderate geologic influences, such as dehydration, recrystallization, and cementation [6,7]. The content of clay grains in claystone is usually greater than 50%, and the particle size is below the range of 0.005~0.0039 mm.…”

Section: Introductionmentioning

confidence: 99%

Effect of Freeze–Thaw Cycles on Microstructure and Hydraulic Characteristics of Claystone: A Case Study of Slope Stability from Open-Pit Mines in Wet Regions

Liu,

Xiang,

Liu

et al. 2024

Water

View full text Add to dashboard Cite

The action of freeze–thaw (F–T) cycles of claystone exerts a profound impact on the slope stability of open-pit mines in water-rich regions. Microstructural changes are observed as a crucial factor in determining the hydraulic characteristics and mechanical behaviors of claystone. The present work integrates a micro-X-ray computed tomography (Micro-CT) scanner, equipped with image processing and three-dimensional (3D) reconstruction capabilities, employed to observe the microstructure of claystone under varying numbers of F–T cycles (0, 10, 20, 30, and 50). Furthermore, seepage numerical simulations based on Micro-CT measurements are conducted to evaluate the hydraulic characteristics. Through meticulous microscopic observation and mechanical analysis, the damage mechanism induced by F–T cycles is revealed and the evolutionary characteristics are analyzed. The two-dimensional (2D) images of 3D reconstructed models unveil the gradual initiation propagation and coalescence of an intricate fissuring network in claystone during the F–T cycles. As the number of F–T cycles increases from 0 to 50, the 3D porosity exhibits exponential growth. Additionally, the influence of F–T cycles substantially enhances the connectivity of fissures. The seepage numerical simulations demonstrate that the evolutionary progression of fissures substantially augments the number of flow paths and enhances permeability. The increase in permeability follows an exponential trend, reflecting the distribution and evolution of fissures under F–T cycles. The impact on permeability arises from a combination of micromechanical properties and the microstructure of claystones. The present research tries to elucidate the microscopic evolution of fissures and their corresponding hydraulic properties in water-saturated claystone, offering significant insights for investigating the slope stability of open-pit mines in regions.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of Freeze–Thaw Cycles on Microstructure and Hydraulic Characteristics of Claystone: A Case Study of Slope Stability from Open-Pit Mines in Wet Regions

Liu,

Xiang,

Liu

et al. 2024

Water

View full text Add to dashboard Cite

show abstract

“…it is an <end-bearing pile=. Large areas of Russia [4,5], Europe [6], China -Suxin et al 2006 and of many other countries of the world are characterized by the spread of ancient hard clay. These deposits can be represented by claystones and their varieties weathered to clays, loams and crushed stones.…”

Section: Introductionmentioning

confidence: 99%

Effect of clay compaction around driven pile and prediction of pile settlement

Ponomaryov

Sychkina

2022

E3S Web Conf.

Self Cite

View full text Add to dashboard Cite

In the article the problem of geotechnical application of clay nd claystone as a base of driven pile foundations has been considered. When using these foundations, a compaction zone is formed in the clay space around the pile. The purpose of this research is to analyze the influence of compaction zones on the results of analytical and numerical calculations for predicting the settlement of a driven pile in layered clay soils. The following tasks were solved: 1) The existing investigations of pile settlement in layered clay soils were analyzed; 2) The characteristics of experimental sites and the parameters of numerical modeling were, methods for testing single field piles in layered clay soils were described; 3) Calculation of single pile settlement was performed carried out by numerical methods with the use of Plaxis 2D software package and by an analytical method; 4) The experimental data were compared with the results of calculations by analytical and numerical methods. The developed calculation scheme with two compaction zones around driven piles can provides reasonable estimates of vertical displacements of the clay base. Based on the results obtained, the authors recommend using the analytical method with due regard for compaction zones in clays and claystones around the driven pile.

show abstract

“…В работах [1][2][3][4] было доказано, что механические свойства грунта основания фундамента определяются особенностями его формирования. В данном исследовании рассмотрены результаты численного моделирования работы забивных свай на грунтовом основании, сложенном аргиллитоподобными глинами пермского возраста, имеющими широкое распространение в европейской и южной части России, странах Западной Европы и Центральной Азии [5,6]. Под действием нагрузки от фундамента в аргиллитоподобных глинах формируется особое напряженно-деформированное состояние (НДС), отличное от НДС в современных глинистых грунтах.…”

Section: Introductionunclassified

“…В отличие от дисперсных грунтов аргиллитоподобные глины имеют цементационные связи. Результаты исследований [6][7][8][9] свидетельствуют о том, что выветривание аргиллитоподобных глин может приводить к снижению несущей способности и увеличению осадки фундамента. Во многом эта неустойчивость к механическим и температурным воздействиям обусловлена наличием у данных грунтов слабого глинистого, железистого и карбонатного цемента.…”

Section: Introductionunclassified

Numerical investigations of work of driven pile on claystones

2019

View full text Add to dashboard Cite

Introduction. Reviewed the features of the work of the pile on Permian claystones with the help of numerical and field experiments, analytical calculations. Materials and methods. Numerical modeling was performed in the Plaxis 3D and Midas GTS NX software packages. Full-scale tests of driven piles are made in accordance with the requirements of GOST 20276-2012. The obtained results are compared with the results of analytical calculations according to SP 24.13330.2011. Results. The scientific novelty of the investigation consists in a comparative analysis of the results of numerical modeling of the interaction of a driving pile with claystones with the results of field tests and analytical calculations. Finite element analysis in software package Plaxis 3D using Hardening Soil model shows higher values of settlement (up to 6 times) in relation to stabilized settlement of full-scale pile tests. Calculations in the software package Midas GTS NX showed overestimated values of pile settlements in relation to full-scale pile tests (13-24 times). Analytical calculations in accordance with SP 24.13330.2011 also showed overestimated (up to 3 times) values of the maximum pile settlement in relation to the stabilized settlement during full-scale pile tests. Conclusions. The calculations by the finite element method in the package Plaxis 3D and Midas GTS NX, by the analytical method according to SP 24.13330.2011, show overestimated values of settlement in relation to the stabilized settlement of piles on claystones. Using the Linear-Elastic model for claystones in numerical calculations in Plaxis 3D provides a value close to the settlement of full-scale pile. However, the use of this model is not fully justified for claystones due to the presence of residual deformations and the nonlinear character of pile settlement during loading. Necessary to correct the existing numerical and analytical methods for calculating pile foundations on claystones. It is necessary to continue the work on the further generalization of the experience of arranging piles on weathered claystones in order to evaluate the long-term work of not only a single pile, but also a pile foundation.

show abstract

Analysis of strain anisotropy and hydroscopic property of clay and claystone

Cited by 7 publications

References 9 publications

Effect of Freeze–Thaw Cycles on Microstructure and Hydraulic Characteristics of Claystone: A Case Study of Slope Stability from Open-Pit Mines in Wet Regions

Effect of Freeze–Thaw Cycles on Microstructure and Hydraulic Characteristics of Claystone: A Case Study of Slope Stability from Open-Pit Mines in Wet Regions

Effect of clay compaction around driven pile and prediction of pile settlement

Numerical investigations of work of driven pile on claystones

Contact Info

Product

Resources

About