Experimental Study on Mechanical Behavior of a New Backfilling Material: Cement-Treated Marine Clay

Backfilling mining method is an overlying strata control way, which is widely used in underground coal mine. This method is effective in preventing and controlling geological disasters such as surface subsidence, mine water inrush, rock burst, and other disasters. Cement-treated marine clay (CMC) is a typical porous media, which has abundant reserves and can be used as a new backfilling material. Therefore, the mechanical characteristics of CMC are very important for overlying strata control in coal mine. To investigate stress-strain behavior of CMC, isotropic consolidated drained (CID) triaxial test and isotropic compression test (ICT) were conducted with different confining pressures in the range of 50–800 kPa. Stress-strain behavior was found similar to those of the overconsolidated stress-strain behavior as well as the pore water pressure versus strain. Stress versus strain curves under lower confining pressure 50–250 kPa presented shear dilatancy. The result shows that the peak strength increased linearly with increasing confining pressure. The internal friction angle and cohesion are 48° and 590 kPa, respectively. Before the confining pressure reaches 727 kPa, which is the primary yielding point, the secant modulus E1 (the secant modulus at 1% axial strain) and the secant modulus E50 (corresponding to the 50% of the peak point) increase initially and decrease afterwards with the increasing of confining pressure. Afterwards, the two parameters increased with increasing confining pressure. The yielding stress occurred in the stage, generating a dramatic decrease in tangent modulus. This study can be a theoretical basis for engineering application of this new backfilling material.

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Effect of Variable Confining Pressure on Cyclic Triaxial Behavior of K0-consolidated Soft Marine Clay

Civil Engineering Journal ◽

10.28991/cej-0309130 ◽

2018 ◽

Vol 4 (4) ◽

pp. 755

Author(s):

Lei Sun

Keyword(s):

Pore Water ◽

Pore Water Pressure ◽

Axial Strain ◽

Water Pressure ◽

Confining Pressure ◽

Stress Path ◽

Cyclic Stress ◽

Marine Clay ◽

Stress Ratios ◽

Variable Confining Pressure

The effect of variable confining pressure (VCP) on the cyclic deformation and cyclic pore water pressure in K0-consolidated saturated soft marine clay were investigated with the help of the cyclic stress-controlled advanced dynamic triaxial test in undrained condition. The testing program encompassed three cyclic deviator stress ratios, CSR=0.189, 0.284 and 0.379 and three stress path inclinations ηampl=3,1 and 0.64. All tests with constant confining pressure (CCP) and variable confining pressure (VCP) have identical initial stress and average stress. The results were analyzed in terms of the accumulative normalized excess pore water pressure rqu recorded at the end of each stress cycle and permanent axial strain, as well as resilient modulus. Limited data suggest that these behavior are significantly affected by both of the VCP and CSR. For a given value of VCP, both of the pore water pressure rqu and permanent axial strains are consistently increase with the increasing values of CSR. However, for a given value of CSR, the extent of the influence of VCP and the trend is substantially depend on the CSR.

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Small-strain behavior of frozen sand in triaxial compression

Canadian Geotechnical Journal ◽

10.1139/t95-047 ◽

1995 ◽

Vol 32 (3) ◽

pp. 428-451 ◽

Cited By ~ 29

Author(s):

Glen R. Andersen ◽

Christopher W. Swan ◽

Charles C. Ladd ◽

John T. Germaine

Keyword(s):

High Pressure ◽

Strain Rate ◽

Yield Stress ◽

Axial Strain ◽

Triaxial Compression ◽

Strain Curve ◽

Confining Pressure ◽

Stress Strain ◽

Strain Behavior ◽

Frozen Sand

The stress–strain behavior of frozen Manchester fine sand has been measured in a high-pressure low-temperature triaxial compression testing system developed for this purpose. This system incorporates DC servomotor technology, lubricated end platens, and on-specimen axial strain devices. A parametric study has investigated the effects of changes in strain rate, confining pressure, sand density, and temperature on behavior for very small strains (0.001%) to very large (> 20%) axial strains. This paper presents constitutive behavior for strain levels up to 1%. On-specimen axial strain measurements enabled the identification of a distinct upper yield stress (knee on the stress–strain curve) and a study of the behavior in this region with a degree of precision not previously reported in the literature. The Young's modulus is independent of strain rate and temperature, increases slightly with sand density in a manner consistent with Counto's model for composite materials, and decreases slightly with confining pressure. In contrast, the upper yield stress is independent of sand density, slightly dependent on confining pressure (considered a second order effect), but is strongly dependent on strain rate and temperature in a fashion similar to that for polycrystalline ice. Key words : frozen sand, high-pressure triaxial compression, strain rate, temperature, modulus, yield stress.

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Stress-strain behavior of remoulded cement-treated Singapore marine clay

Geomechanics and Geotechnics ◽

10.1201/b10528-31 ◽

2010 ◽

pp. 177-182 ◽

Cited By ~ 2

Author(s):

Huawen Xiao ◽

Fook Lee

Keyword(s):

Marine Clay ◽

Stress Strain ◽

Strain Behavior

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Normalized Stress-Strain Behavior of Yingkou Clay

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.838-841.47 ◽

2013 ◽

Vol 838-841 ◽

pp. 47-52

Author(s):

Fu Yi ◽

Hong Yu Wang

Keyword(s):

Strain Hardening ◽

Principal Stress ◽

Soft Soil ◽

Confining Pressure ◽

Stress Strain ◽

Strain Behavior ◽

Strain Relationship ◽

Relationship Of ◽

Is Strain

In order to systemic study the normalized stress-strain relationship behavior of Yingkou clay. By the consolidated undrained triaxial sherar test of Yingkou clay, obtaining that stress-strain relationship is strain hardening under different confining pressures.A kind of cementation structure in the soil directly affects soft soil strength.And the paper contrast four kinds of normalized factors to study stress-strain characteristics,which are confining pressurethe average consolidation pressureand the ultimate value of principal stress.The results indicate that the normalized degree is more accurate when used value of principal stress and as normalized factor. Meanwhile the normalized stress-strain relationship of Yingkou clay under consolidated undrained condition is established,which can well predict the stress-strain relationship under different confining pressure.

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Effects of Confining Pressure and Pore Water Pressure on the Strain Behavior and Deformation Property of Aji Granite under Triaxial Compression Test

The Journal of the Geological Society of Japan ◽

10.5575/geosoc.2016.0041 ◽

2016 ◽

Vol 122 (11) ◽

pp. 603-615 ◽

Cited By ~ 4

Author(s):

Kazuki Sawayama ◽

Ikuo Katayama

Keyword(s):

Pore Water ◽

Compression Test ◽

Deformation Property ◽

Pore Water Pressure ◽

Water Pressure ◽

Triaxial Compression ◽

Confining Pressure ◽

Triaxial Compression Test ◽

Strain Behavior

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Behavior of Weakly Cemented Rock with Different Moisture Contents under Various Tri-Axial Loading States

Energies ◽

10.3390/en12081563 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1563

Author(s):

Honglin Liu ◽

Dongsheng Zhang ◽

Hongchao Zhao ◽

Mingbo Chi ◽

Wei Yu

Keyword(s):

Residual Stress ◽

Moisture Content ◽

Water Conservation ◽

Peak Stress ◽

Confining Pressure ◽

Geological Condition ◽

Stress Strain ◽

Strain Behavior ◽

Moisture Contents ◽

Sandy Mudstone

To better understand the physical and mechanical behavior of weakly cemented rock with different moisture contents for the success of water-preserved mining, this paper presents the systematic tri-axial compression tests on three typical rock samples (i.e., mudstone, sandstone, and sandy mudstone) sampled from Ili mining area, where the environmental requirements for water conservation are significantly strict. Both the influences of moisture content and confining pressure on the failure mode and the stress-strain behavior of weakly cemented rock have been discussed and compared with each other. Test results showed that: (1) compared to sandstone and sandy mudstone, both the peak stress and residual stress of the weakly cemented mudstone are much more sensitive to confining pressure and moisture content. In detail, the peak stress is very relevant to moisture content, whereas, the residual stress is more sensitive to the confining pressure, (2) with the increase of moisture content, both the yield and ductility of weakly cemented mudstone have been significantly enhanced. However, a similar experimental observation has been found for sandstone and sandy mudstone, and (3) the microstructure and the mineral component are believed to be the two main factors leading to the scatter in terms of the stress-strain behavior for different weakly cemented rocks. Experimental results and discussions presented in this paper can provide the guideline for further research on the application of water-preserved mining in other coal mines with a similar geological condition.

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