Non-linear creep damage model of sandstone under freeze-thaw cycle

Using the fast freeze-thaw test method, we tested the loss modulus and compressive strength of steel slag-limestone powder concrete after 0,25 times,50 times,75 times,100 times freeze-thaw cycle,studied the mechanical properties and frost resistance performance after the freeze-thaw cycle. The results showed that adding a certain amount of steel slag-limestone powder does not affect the anti-frost property of concrete; established different dosage of steel slag concrete freeze-thaw damage model: y = a + bx + cx2, degree of fitting is better; large quantity of steel slag used in concrete shall be a wider range of research.

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Experimental investigation on combined modification for micro physicochemical characteristics of coal by compound reagents and liquid nitrogen freeze-thaw cycle

Fuel ◽

10.1016/j.fuel.2021.120287 ◽

2021 ◽

Vol 292 ◽

pp. 120287

Author(s):

Weibo Han ◽

Gang Zhou ◽

Junpeng Wang ◽

Wenjing Jiang ◽

Qian Zhang ◽

...

Keyword(s):

Experimental Investigation ◽

Liquid Nitrogen ◽

Physicochemical Characteristics ◽

Freeze Thaw ◽

Thaw Cycle ◽

Freeze Thaw Cycle

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The effect of freeze–thaw cycle on the low-temperature properties of asphalt fine aggregate matrix utilizing bending beam rheometer

Cold Regions Science and Technology ◽

10.1016/j.coldregions.2016.02.008 ◽

2016 ◽

Vol 125 ◽

pp. 101-107 ◽

Cited By ~ 20

Author(s):

Xiangbing Gong ◽

Pedro Romero ◽

Zejiao Dong ◽

Daniel Scott Sudbury

Keyword(s):

Low Temperature ◽

Fine Aggregate ◽

Bending Beam Rheometer ◽

Freeze Thaw ◽

Thaw Cycle ◽

Freeze Thaw Cycle ◽

Fine Aggregate Matrix

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Effect of freeze–thaw cycle on physical and mechanical properties and damage characteristics of sandstone

Scientific Reports ◽

10.1038/s41598-021-91842-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Longxiao Chen ◽

Kesheng Li ◽

Guilei Song ◽

Deng Zhang ◽

Chuanxiao Liu

Keyword(s):

Mechanical Properties ◽

Shear Failure ◽

Triaxial Compression ◽

Physical And Mechanical Properties ◽

Freeze Thaw ◽

Damage Characteristics ◽

Large Pore ◽

Natural Rock ◽

Thaw Cycle ◽

Freeze Thaw Cycle

AbstractRock deterioration under freeze–thaw cycles is a concern for in-service tunnel in cold regions. Previous studies focused on the change of rock mechanical properties under unidirectional stress, but the natural rock mass is under three dimensional stresses. This paper investigates influences of the number of freeze–thaw cycle on sandstone under low confining pressure. Twelve sandstone samples were tested subjected to triaxial compression. Additionally, the damage characteristics of sandstone internal microstructure were obtained by using acoustic emission (AE) and mercury intrusion porosimetry. Results indicated that the mechanical properties of sandstone were significantly reduced by freeze–thaw effect. Sandstone’ peak strength and elastic modulus were 7.28–37.96% and 6.38–40.87% less than for the control, respectively. The proportion of super-large pore and large pore in sandstone increased by 19.53–81.19%. We attributed the reduced sandstone’ mechanical properties to the degenerated sandstone microstructure, which, in turn, was associated with increased sandstone macropores. The macroscopic failure pattern of sandstone changed from splitting failure to shear failure with an increasing of freeze–thaw cycles. Moreover, the activity of AE signal increased at each stage, and the cumulative ringing count also showed upward trend with the increase of freeze–thaw number.

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An improved nonlinear damage model of rocks considering initial damage and damage evolution

International Journal of Damage Mechanics ◽

10.1177/1056789520909531 ◽

2020 ◽

Vol 29 (7) ◽

pp. 1117-1137 ◽

Cited By ~ 3

Author(s):

Wenlin Feng ◽

Chunsheng Qiao ◽

Shuangjian Niu ◽

Zhao Yang ◽

Tan Wang

Keyword(s):

Damage Evolution ◽

Least Squares Method ◽

Damage Model ◽

Creep Damage ◽

Secondary Creep ◽

Nonlinear Creep ◽

Creep Failure ◽

Initial Damage ◽

Nonlinear Damage Model ◽

Creep Damage Model

The experimental results show that the creep properties of the rocks are affected by the initial damage, and the damage evolution also has a significant impact on the time-dependent properties of the rocks during the creep. However, the effects of the initial damage and the damage evolution are seldom considered in the current study of the rocks' creep models. In this paper, a new nonlinear creep damage model is proposed based on the multistage creep test results of the sandstones with different damage degrees. The new nonlinear creep damage model is improved based on the Nishihara model. The influences of the initial damage and the damage evolution on the components in the Nishihara model are considered. The creep damage model can not only describe the changes in three creep stages, namely, the primary creep, the secondary creep, and the tertiary creep, but also reflect the influence of the initial damage and the damage evolution on creep failure. The nonlinear least squares method is used to determine the parameters in the nonlinear creep damage model. The consistency between the experimental data and the predicted results indicates the applicability of the nonlinear damage model to accurately predict the creep deformation of the rocks with initial damage.

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Strength and Microscopic Damage Mechanism of Yellow Sandstone with Holes under Freezing and Thawing

Advances in Civil Engineering ◽

10.1155/2020/5921901 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Huren Rong ◽

Jingyu Gu ◽

Miren Rong ◽

Hong Liu ◽

Jiayao Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Pore Size ◽

Power Function ◽

Damage Mechanism ◽

Uniaxial Compression Test ◽

Freezing And Thawing ◽

Freeze Thaw ◽

Thaw Cycle ◽

Freeze Thaw Cycle ◽

Microscopic Damage

In order to study the damage characteristics of the yellow sandstone containing pores under the freeze-thaw cycle, the uniaxial compression test of saturated water-stained yellow sandstones with different freeze-thaw cycles was carried out by rock servo press, the microstructure was qualitatively analyzed by Zeiss 508 stereo microscope, and the microdamage mechanism was quantitatively studied by using specific surface area and pore size analyzer. The mechanism of weakening mechanical properties of single-hole yellow sandstone was expounded from the perspective of microstructure. The results show the following. (1) The number of freeze-thaw cycles and single-pore diameter have significant effects on the strength and elastic modulus of the yellow sandstone; the more the freeze-thaw cycles and the larger the pore size, the lower the strength of the yellow sandstone. (2) The damage modes of the yellow sandstone containing pores under the freeze-thaw cycle are divided into five types, and the yellow sandstone with pores is divided into two areas: the periphery of the hole and the distance from the hole; as the number of freeze-thaw cycles increases, different regions show different microscopic damage patterns. (3) The damage degree of yellow sandstone is different with freeze-thaw cycle and pore size. Freeze-thaw not only affects the mechanical properties of yellow sandstone but also accelerates the damage process of pores. (4) The damage of the yellow sandstone by freeze-thaw is logarithmic function, and the damage of the yellow sandstone is a power function. The damage equation of the yellow sandstone with pores under the freezing and thawing is a log-power function nonlinear change law and presents a good correlation.

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Studies the Properties of Polyaspartic Polyurea Coated Concrete under Coaction of Salt Fog and Freeze-Thaw

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.455-456.781 ◽

2012 ◽

Vol 455-456 ◽

pp. 781-785

Author(s):

Ping Lu ◽

Xin Mao Li ◽

Xue Qiang Ma ◽

Wei Bo Huang

Keyword(s):

Elastic Modulus ◽

Frost Resistance ◽

Dynamic Elastic Modulus ◽

Freeze Thaw ◽

Decrease Rate ◽

Thaw Cycle ◽

Freeze Thaw Cycle ◽

Salt Fog

. This paper mainly studied the properties of PAE polyurea coated concrete under coactions of salt fog and freeze-thaw. After exposed salt fog conditions for 200d, T3, B2, F2 and TM four coated concrete relative dynamic elastic modulus have small changes, but different coated concrete variation amplitude is different. T3 coated concrete after 100 times of freeze-thaw cycle the relative dynamic elastic modulus began to drop, 200 times freeze-thaw cycle ends, relative dynamic elastic modulus variation is the largest, decrease rate is 95%, TM concrete during 200 times freeze-thaw cycle, relative dynamic elastic modulus almost no change, B2 concrete and F2 concrete the extent of change between coating T3 and TM. After 300 times the freeze-thaw cycle coated concrete didn't appear freeze-thaw damage phenomenon. Four kinds of coating concrete relative dynamic elastic modulus variation by large to small order: T3 coated concrete > B2 coated concrete >F2 coated concrete > TM coated concrete, concrete with the same 200d rule. Frost resistance order, by contrast, TM coated concrete > B2 coated concrete > F2 coated concrete > T3 coated concrete.

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