• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.365-368
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• 2002

This paper considers transference number in calculating diffusion coefficient of chloride ions of concrete and mercury intrusion porosimetry to investigate the volume and distribution of pore size, respectively, analyzing and discussing the property of resistance to chloride ion of concrete with granulated blast furnace slag. The experimental results show that the diffusion coefficient of chloride ion decreases with the rise of quantity of granulated blast furnace slag and pore structure of concrete with granulated blast furnace slag is different from that of OPC concrete. And from the results of regression analysis, the result showed that the diffusion coefficient of chloride ions is affected by capillary pore above 50nm.

• Composites Research
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• v.31 no.2
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• pp.76-81
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• 2018

In this study, the elemental mercury removal behaviors of silver-plated porous carbons materials were investigated. The pore structures and total pore volumes of the hybrid materials were analyzed by $N_2$ adsorption/desorption analysis at 77 K. The pore structures and surface morphologies of the hybrid materials were characterized by XRD and SEM, respectively. The elemental mercury adsorption capacities of all silver-plated porous carbons hybrid materials were higher than those of the as-received samples, despite the fact that the specific surface areas and total pore volumes decreased with increasing metal loading time. It was found that silver nanoparticles showed excellent elemental mercury removal behaviors in carbonaceous hybrid materials.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.107-110
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• 1999

The objective of this study is to obtain characteristics of early age pore-structure and carbonation of concrete using ground granulated blast furnace slag (GGBFS). The durability of GGBFS concrete should be evaluated for wide use of the GGBFS. As for that evaluation, an analysis on early age pore-structure characteristics of GGBFS concrete are very important, Carbonation depths of GGBFS concrete, which are known to be larger than that of OPC, are different according to replacement ratios and fineness of slag. Because sea sand as fine aggregate is much used recently, it is also necessary to analyze characteristics of carbonation of GGBFS concrete. In this study, The micro-pore structure formation characteristics of GGBFS concrete are obtained through the test of GGBFS mortars with different fineness and replacement ratio of GGBFS. The carbonation of GGBFS concrete is also investigated by acclerated carbonation test for early age GGBFS concrete.

• Geotechnical Engineering
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• v.6 no.4
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• pp.65-74
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• 1990

This paper presents triaxial test (CIVC and CKOUC) results on normally consolidated deep sea clay samples. Based on the test results the pore pressure-strain relations for both isotropicaly and anisotropicaly consgidated samples are expressed with hyperbolic functions of the major princpal strain. The analysis of the difference in pore pressure behavior due to the anisotropy in consolidation stress is carried out with the effective stress pathos of CIVC and CKOUC and finds a factor which correlates the pore pressure of two types of test.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.273-278
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• 1993

Using water vapor (de)sorption isotherm, pore structure analyses were performed for hardened cement pastes by a combination of the "MP-method" for the micropores and the "corrected modelless method" for the wide pores. This work was carried out to investigate the pore structure and to understand the microstructural basis of alumina cement developing much higher strength than Portland cement. Alumina cement shows extremely low microporosity and its wide pores are also composed mainlyof pores with very small radii. And the pore structure analysis results are consistent with the high strength property of alumina cement.y of alumina cement.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.188-193
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• 2003

To predict changes in biomechanical parameters such as intradiscal pressure, and the shock absorbing mechanism in the spinal motion segment under different impact duration/loading rates, a three dimensional L3/L4 motion segment finite element model was modified to incorporate the poroelastic properties of the motion segment. The results were analyzed under variable impact duration for normal and degenerated discs. For short impact duration and a given maximum compressive force, relatively high cancellous pore pressure was generated as compared with a case of long impact duration, although the amount of impulse was increased. In contrast relatively constant pore pressure was generated in the nucleus. Disc degeneration increased pore pressure in the disc and decreased pore pressure in the cancellous core, which is more vulnerable to compressive fracture compared with intact case.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.2
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• pp.37-44
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• 2008

A theoretical equation was proposed to consider the effect of ponding for the excess pore water pressure in agricultural reservoir on soft clay ground. The value of excess pore water pressure predicted using the proposed equation was compared to those predicted with the Terzaghi's method and the finite difference method(FDM), respectively, for the purpose of verification. The degree of consolidation according to ponding predicted by applying the proposed equation was close to the observed degree of consolidation on the double drainage condition(at DP-3) but it was less than the observed degree of consolidation on the single drainage condition(at DP-5). The equation was very applicable to practice because the analysis result by the equation was close to the observed data.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.201-208
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• 2000

In this study, the behavior of saturated sandy soils under dynamic loads - pore water pressure and effective stress - was investigated using Disturbed State Concept(DSC) model. The model parameters are evaluated from laboratory test data. During the process of loading and reverse loading, DSC model is utilized to trace strain-hardening and cyclic softening behavior. The procedure of back prediction proposed in this study are verified by comparing with laboratory test results. From the back prediction of pore water pressure and effective mean pressure under cyclic loading, excess pore water pressure increases up to initial effective confining pressure and effective mean pressure decrease close to zero in good greement with laboratory test results. Those results represent the liquefaction of saturated sandy soils under dynamic loads. The number of cycles at initial liquefaction using the model prediction is in good agreement with laboratory test results. Therefore, the results of this study state that the liquefaction of saturated sandy soils can be explained by the effective tress analysis.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.3
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• pp.104-110
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• 2010

Cyclic deformations of polymer foam film are simulated using the finite element method. Material of polymer foam film is polypropylene (PP). The calculated polymer foam film is micro-scale thin film has cellular structure. The polymer foam film is used in ferro-electret applications. The polymer foam film is idealized to one cell structure as lens shaped stretched truncated octahedron model. Cyclic deformation is performed by uniaxial stretching. Stretching direction is perpendicular to plane of cellular film. Various cyclic strain amplitudes, pore wall thicknesses, pore shape are investigated to find deformation tendency of cellular structure. Consequently, cellular structure has various macroscopic stresses on cyclic deformation with various pore thickness and pore shape.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.162-163
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• 2017

This study investigated the properties of lightweight foamed concrete by using synthetic foaming agent and artificial lightweight aggregate. The effects of artificial lightweight sizes on the compressive strength, density and pore structure of the concrete were investigated. The samples were assessed by MIP analysis and simultaneous SEM was used to study their pore distribution. This study showed the improvement of important properties of lightweight foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. This is for the purpose of providing basic data for the use of lightweight foamed concrete through improvement on the problem such as unstability, falling in fluidity and the strength of existed foaming agent.