scholarly journals Pore-Size Distribution Evolution of Intact, Compacted, and Saturated Loess from China during Consolidation and Shearing

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Ping Li ◽  
Shengjun Shao ◽  
Tao Xiao ◽  
Dandan Zhu
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Dominant Role ◽  
Confining Stress ◽  
Mechanical Responses ◽  
The Stability ◽  
Compacted Loess ◽  
Intact Loess

To examine the pore-size distribution (PSD) evolution of intact, compacted, and saturated loess during deformation associated with consolidation or shearing, nominally identical specimens were consolidated to different confining stresses or sheared to sequential axial strains under the same confining stress, and the PSD of each deformed specimen was characterized using the Mercury intrusion porosimetry (MIP) technique. The results show that the PSD evolution during consolidation is similar to that during shearing, suggesting that the PSD evolution depends mainly on whether the soil volume contracts or expands. The volumetric contraction results mainly from compression of interaggregate pores, and the intra-aggregate PSD or intra-aggregate pores are not affected. In compacted and saturated loess, interaggregate pores are compressed from the larger to the smaller, while in intact loess, the PSD evolution depends on whether the soil yields. This difference arises from different cementations that dominate particle associating in three soils. In intact loess, carbonate cementations that can be damaged by remolding and loading contribute greatly to particle associating. As a result, the stability of a pore is controlled not only by its size but also by carbonate cementations at surrounding particle contacts. Clay cementations that play the dominant role in particle aggregating in compacted loess are resistant to loading; thus, aggregates could not be destroyed by loading and the mechanical responses of compacted loess are in fact interactions among aggregates. Both carbonate and clay cementations can fail under the combined effect of loading and inundation, leading to disintegration of aggregates and turning of the loess structure from the double-structured to the uniform type.

scholarly journals Ink-bottle Effect and Pore Size Distribution of Cementitious Materials Identified by Pressurization–Depressurization Cycling Mercury Intrusion Porosimetry

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1454 ◽  
Author(s):  
Yong Zhang ◽  
Bin Yang ◽  
Zhengxian Yang ◽  
Guang Ye
Keyword(s):  
Pore Structure ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Cementitious Materials ◽  
Limestone Powder ◽  
Accurate Estimation ◽  
Mercury Intrusion ◽  
Pore Size Distributions

Capturing the long-term performance of concrete must be underpinned by a detailed understanding of the pore structure. Mercury intrusion porosimetry (MIP) is a widely used technique for pore structure characterization. However, it has been proven inappropriate to measure the pore size distribution of cementitious materials due to the ink-bottle effect. MIP with cyclic pressurization–depressurization can overcome the ink-bottle effect and enables a distinction between large (ink-bottle) pores and small (throat) pores. In this paper, pressurization–depressurization cycling mercury intrusion porosimetry (PDC-MIP) is adopted to characterize the pore structure in a range of cementitious pastes cured from 28 to 370 days. The results indicate that PDC-MIP provides a more accurate estimation of the pore size distribution in cementitious pastes than the standard MIP. Bimodal pore size distributions can be obtained by performing PDC-MIP measurements on cementitious pastes, regardless of the age. Water–binder ratio, fly ash and limestone powder have considerable influences on the formation of capillary pores ranging from 0.01 to 0.5 µm.

Hydraulic conductivity of clay mixed with nanomaterials

2015 ◽  
Vol 52 (6) ◽  
pp. 808-811 ◽  
Author(s):  
C.W.W. Ng ◽  
J.L. Coo
Keyword(s):  
Hydraulic Conductivity ◽  
Aluminum Oxide ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Flow Paths ◽  
Mercury Intrusion ◽  
Flexible Wall ◽  
Conductivity Behavior

The focus of this note is to investigate the hydraulic conductivity behavior of clay mixed with nanomaterials. Two different nanomaterials — namely, gamma-aluminum oxide powder (γ-Al2O3) and nano-copper oxide (CuO) — were selected and mixed with clay at different percentages (i.e., 2%, 4%, and 6%). Hydraulic conductivity tests were carried out in a flexible wall permeameter following the ASTM D5084 standard. Mercury intrusion porosimetry (MIP) tests were also carried out to determine the pore-size distribution. At 2% of γ-Al2O3 and nano-CuO, the hydraulic conductivity of clay decreased 30% and 45%, respectively. As the proportion of the nanomaterial increases, the reduction of hydraulic conductivity becomes less prominent as flow paths devoid of nanomaterials are unlikely. Reduction of hydraulic conductivity is due to the pores of clay being clogged by the nanomaterial. Pore-size distribution curves show that the largest pore size reduced by 20% when clay was mixed with 4% nano-CuO.

scholarly journals Pore Size Distribution of Rocks Determined by Mercury Intrusion Porosimetry

2016 ◽  
Vol 57 (5) ◽  
pp. 201-212 ◽  
Author(s):  
Weiren LIN ◽  
Manabu TAKAHASHI ◽  
Daisaku SATO ◽  
En-Chao YEH ◽  
Yoshitaka HASHIMOTO ◽  
...  
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Mercury Intrusion

scholarly journals Physical parameters of Fluvisols on flooded and non-flooded terraces

2017 ◽  
Vol 31 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Milena Kercheva ◽  
Zofia Sokołowska ◽  
Mieczysław Hajnos ◽  
Kamil Skic ◽  
Toma Shishkov
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Water Retention Curve ◽  
Anthropogenic Factors ◽  
Physical Parameters ◽  
Water Desorption ◽  
Mercury Intrusion ◽  
The Impact

Abstract The heterogeneity of soil physical properties of Fluvisols, lack of large pristine areas, and different moisture regimes on non-flooded and flooded terraces impede the possibility to find a soil profile which can serve as a baseline for estimating the impact of natural or anthropogenic factors on soil evolution. The aim of this study is to compare the pore size distribution of pristine Fluvisols on flooded and non-flooded terraces using the method of the soil water retention curve, mercury intrusion porosimetry, nitrogen adsorption isotherms, and water vapour sorption. The pore size distribution of humic horizons of pristine Fluvisols on the non-flooded terrace differs from pore size distribution of Fluvisols on the flooded terrace. The peaks of textural and structural pores are higher in the humic horizons under more humid conditions. The structural characteristics of subsoil horizons depend on soil texture and evolution stage. The peaks of textural pores at about 1 mm diminish with lowering of the soil organic content. Structureless horizons are characterized by uni-modal pore size distribution. Although the content of structural pores of the subsoil horizons of Fluvisols on the non-flooded terrace is low, these pores are represented by biopores, as the coefficient of filtration is moderately high. The difference between non-flooded and flooded profiles is well expressed by the available water storage, volume and mean radius of pores, obtained by mercury intrusion porosimetry and water desorption, which are higher in the surface horizons of frequently flooded Fluvisols.

Chloride Permeability Of Concrete Containing A Flyash And A Blastfurnace Slag

1988 ◽  
Vol 137 ◽  
Author(s):  
Mitsunori Kawamura ◽  
Kazuyuki Torii
Keyword(s):  
Portland Cement ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Chloride Permeability ◽  
Curing Conditions ◽  
Mercury Intrusion ◽  
Blastfurnace Slag ◽  
Low Humidity

AbstractThe effects of curing conditions on the chloride permeability of concrete with various replacements of Portland cement by a flyash and a blastfurnace slag was investigated. In order to relate the porosity and pore size distribution of concretes to their chloride permeability, mercury intrusion porosimetry measurements were also conducted. The results showed that exposure of concretes to a relatively low humidity at early ages increased their chloride permeability. It was also found that the chloride permeability of concrete increased proportionally with increasing volume of pores larger than 0.1 μm in diameter.

scholarly journals POROSITY AND PORE SIZE DISTRIBUTION OF RECENT AND ANCIENT BURIED PHOEBE ZHENNAN WOOD DETERMINED BY MERCURY INTRUSION POROSIMETRY

Wood Research ◽  
2021 ◽  
Vol 66 (2) ◽  
pp. 277-284
Author(s):  
Jialin Zhang ◽  
Hui Xiao ◽  
Yuzhu Chen ◽  
Jinqiu Qi ◽  
Jiulong Xie
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Pore Diameter ◽  
Mercury Intrusion Porosimetry ◽  
Sorption Behaviour ◽  
Mercury Intrusion ◽  
Pore Area ◽  
Phoebe Zhennan ◽  
Ancient Buried Wood

The porosity and pore size distribution of recent and ancient buried Phoebe zhennan are studied in this paper by means of mercury intrusion porosimetry. The results show that the micropore and mesopore diameters of recent and buried wood are mainly distributed in range of 40.3 nm and 183.1 nm respectively, while the macropore in 45276.6 nm and 3503.9 nm separately. For both samples, the pores with diameters below 349.9 nm account for about 60% of the total intrusion volume, and contribute more than 98% of the surface area. The cumulative pore area of recent wood is slightly greater and the pore diameter ranges from 50.3 nm to 349.9 nm. While the cumulative pore area of buried wood is significantly larger than and the pore diameter ranges until 50.3 nm. These results can provide information for further investigations on the sorption behaviour and the liquid permeability of ancient buried wood.

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