Mechanical and permeability characteristics of rock under hydro-mechanical coupling conditions

Wang, Lu; Liu, Jianfeng; Pei, Jianyong; Xu, Hongwu; Yu, Bo

doi:10.1007/s12665-015-4190-4

Cited by 59 publications

(29 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hydrostatic or confined compression usually makes the mudstone more compact and less permeable. However, many CTC tests on sandstone [26][27][28][29][30][31][32][33], granite [34][35][36], limestone [33,37,38], etc. have revealed that the permeability of the sample gradually increases until failure after the initial reduction during compression, and the formation of faults leads to a jump in the permeability magnitude; the variation in mudstone permeability shows the same trend during compression with a relatively low effective confining pressure [28,39,40].…”

Section: Introductionmentioning

confidence: 99%

Investigation of the Effect of Confining Pressure on the Mechanics-Permeability Behavior of Mudstone under Triaxial Compression

et al. 2019

View full text Add to dashboard Cite

Injecting CO 2 into a reservoir disturbs the geostress field, which leads to variations in the permeability of caprock and affects its sealing performance. In this paper, the evolution characteristics of the permeability of Yingcheng mudstone were experimentally studied during deviatoric compression under different confining pressures. As the confining pressure increased, the strength of the mudstone increased bilinearly, the angle between the fault and the maximum principle stress increased, and the fault became flatter. During compression, the permeability of mudstone first decreased and then increased and the turning point of the permeability was between the onset of dilatancy and the turning point of volumetric strain; when the fault formed, the permeability increased sharply and the fault-induced increment was reduced exponentially with increasing confining pressure. In addition, the mudstone transformed to the ductile failure mode when the effective confining pressure was greater than 35 MPa, which means that the permeability did not jump within a small strain. Finally, a practical strain-based model of permeability evolution that separately considers compaction and dilatancy was proposed, and the predicted permeability values were in good agreement with the experimental results. This study revealed the effect of confining pressure on permeability evolution during compression and can help evaluate the sealing ability of mudstone caprock.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigation of the Effect of Confining Pressure on the Mechanics-Permeability Behavior of Mudstone under Triaxial Compression

et al. 2019

View full text Add to dashboard Cite

show abstract

“…In order to study the evolution of permeability of coal measured rock under different stress states and levels, lots of experiments are conducted to study the mechanism of permeability, especially focused on the relation between permeability and stress-strain curve, as well as the relation between permeability and confining pressure. Permeability tests of coal measured rock during the whole stress-strain process were conducted by scholars [9][10][11][12][13][14][15] indicating that permeability decreased slightly in the initial stage with the increase of axial strain, which was caused by the closure of primary cracks. Then, permeability increased slowly with the increase of axial strain due to initiation of new cracks and expansion of original cracks.…”

Section: Introductionmentioning

confidence: 99%

Study on the Permeability Evolution and Its Formation Mechanism of Xiaojihan Aquifer Coal Seam under Plastic Flow

Guo

Liu

et al. 2020

Geofluids

View full text Add to dashboard Cite

Study on permeability evolution of an aquifer coal seam in Western China is of great significance for preventing water inrush disaster and realizing water-conserving coal mining. The permeability evolution of an aquifer coal seam is related to a loading path closely under plastic flow. In this work, permeability variations of the Xiaojihan water-bearing coal seam and Longde nonwater coal seam are researched using a transient method under plastic flow. The experiment results indicated the following: (1) Under the same axial strain, the permeability, relative residual strain, and confining pressure influence coefficient of Xiaojihan coal specimens all decrease in plastic flow with the increase of loading-unloading times and confining pressure, while the permeability recovery coefficient increases during this process. (2) The permeability of Xiaojihan water-bearing coal specimens decreases with the growth of axial strain in plastic flow, resulting in the increase of relative residual strain and reinforcement of plasticity. Besides, the confining pressure influence coefficient decreases and the permeability recovery coefficient decreases slightly with the axial strain. (3) Finally, the permeability of Xiaojihan coal specimens is greater than that of Longde coal specimens, while the confining pressure influence coefficient and permeability recovery coefficient of Longde coal specimens are greater than those of Xiaojihan coal specimens. The closure rate of internal cracks of the water-bearing coal specimen is lower than that of the nonwater coal specimen, which is beneficial for water storage and transport.

show abstract

“…In addition, the researches show that the variation law and sensitivity of permeability under different external loads are different [11][12][13]. By analyzing the stress-strain-permeability curves, the relationship between rock deformation mechanism and permeability is obtained, which indicates that permeability is controlled by crack characteristics [14,15].…”

Section: Introductionmentioning

confidence: 99%

Permeability Characteristic and Failure Behavior of Filled Cracked Rock in the Triaxial Seepage Experiment

Liu

Zhu

Liu

2019

Advances in Civil Engineering

View full text Add to dashboard Cite

Filling is commonly found in natural cracked rock mass. As the weakest part of the rock, the filling properties directly affect the rock deformation and strength, permeability, and so on and affect the safety and stability of the rock mass engineering. In this study, a single slit has been preset in sandstones and filled with different physical properties materials. Based on the laboratory triaxial seepage test, the permeability and strength characteristics of filled cracked sandstones are analyzed, and the failure modes are obtained. The main findings of this study are as follows: (1) The permeability coefficient peak value of the filled cracked rock appears before the stress peak. (2) At the same confining pressure growth rate, the peak stress growth rate of the filled cracked rock is generally higher than that of the intact rock and the strength growth rate of the cracked rock increases with the length of the fracture. The strength characteristics of the filling in the uniaxial compression tests and triaxial seepage tests are significantly affected by the hydraulic properties. (3) The strength and permeability coefficients of cracked rock filled with cement mortar are more sensitive to the change of confining pressure, while under the same condition, the ones of cracked rock filled with gypsum mortar are stable. (4) According to the failure mechanism, under the seepage stress, the secondary cracks can be divided into 3 types and the failure modes can be divided into 2 types.

show abstract

Mechanical and permeability characteristics of rock under hydro-mechanical coupling conditions

Cited by 59 publications

References 25 publications

Investigation of the Effect of Confining Pressure on the Mechanics-Permeability Behavior of Mudstone under Triaxial Compression

Investigation of the Effect of Confining Pressure on the Mechanics-Permeability Behavior of Mudstone under Triaxial Compression

Study on the Permeability Evolution and Its Formation Mechanism of Xiaojihan Aquifer Coal Seam under Plastic Flow

Permeability Characteristic and Failure Behavior of Filled Cracked Rock in the Triaxial Seepage Experiment

Contact Info

Product

Resources

About