• Title/Summary/Keyword: Consolidation Analysis

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An Implicit Stress Integration for the Constitutive Relationship of Clays (점토의 구성관계에 대한 내재적인 응력적분)

  • 오세붕
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.92-98
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    • 1998
  • Nonlinear finite element analyses of one dimensional consolidation problem were performed using an anisotropic hardening constitutive model. For the analyses, the anisotropic hardening elasto-plastic constitutive model based on the generalized isotropic hardening(GIH) rule was implemented into a nonlinear finite element analysis program, PLASTIC. In order to preserve the accuracy of the finite element solution for nonlinear problems, an implicit stress integration algorithm was employed. A consistent tangent moduli could also ensure the quadratic convergence of Newton's method. As a result, the nonlinear solution was accurately calculated and was converged to be asymptotically quadratic. In a consolidation problem, the relationship between load and settlement and between settlement and time vertical was analyzed comparing with results using the Cam-clay type model and the final consolidation settlement and the duration of primary consolidation could be evaluated rigorously using the GIH constitutive model.

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A Study of Three Dimensional Numerical Analysis on Vacuum Consolidation

  • Chung, Youn ln
    • Geotechnical Engineering
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    • v.13 no.3
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    • pp.5-20
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    • 1997
  • A governing equation of uncoupled three dimensional finite strain theory of consolidation is presented. This equation is suitable for relatively thick layers, possessing large strain, non-linear material property, and variable permeability. A special numerical solution procedure has to be adopted for the finite difference scheme because the solution is not stable in using Forward-Time Centered-Space (FTCS) method and the governing equation is highly non-linear. The solution is capable of predicting settlement with respect to time. The results predicted by the developed method of analysis have been compared with those of experimental tests on different types of highly compressible soils with vertical wick drain. The uncoupled three dimensional finite strain theory of consolidation appears to predict settlement behavior well. A detailed comparison shows good agreement in terms of total settlement, and reasonable agreement with respect to time.

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Application of Numerical Analysis for Sand Drain by the Multi-purpose Program of Soft Foundation Analysis (연약식반교양공법에 이용될 범용프로그램의 Sand Drain 공법에의 적용)

  • 박병기;정진섭
    • Geotechnical Engineering
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    • v.1 no.2
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    • pp.17-26
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    • 1985
  • This study was carried out for the purpose of comparing in reference to sand drain in the next three different cases. First, The case of drain material (sand pile) has some rigidity during embankment and consolidation. Second, In usual case of no rigidity as a paper drain without permeability during embankment and consolidation Third, Check up clay behavior when above the two cases carried out respectively. This FEM analysis is consisted with Biot's consolidation equation when it is used for Christian Boehmer's numerical technique. The main results are obtained from above the Analysis When sand drain has some rigidity, the lateral and vertical deformation of clay foundation is restrained considerable amount and .exhibited bearing capacity of load as a pile According to the foundation in drained condition and untrained condition, the results are much variable in this analysis method. Also, The behaviors of stress path and pore water pressure met our expectation during , consolidation. This analysis should be considered to put into use of sand drain and design in future.

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A Study on Self-Weight Consolidation Characteristics in Dredged and Reclaimed Clay (준설매립 점토의 자중압밀 특성에 관한 연구)

  • Lee, Song;Yang, Tae Seon;Hwang, Koou Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.4
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    • pp.953-963
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    • 1994
  • Treatment techniques of soft clay layers is needed sophisticated technology in civil engineering. Especially, dredged and reclaimed clay has high liquid limit and water content, so it is difficult to use. Now it comes to the applicability as good construction materials by predicting the behaviors. This paper is to evaluate the characteristics of sedimentation and self-weight consolidation of extremely soft clay, and is to find the way of applying model test result of reconstructing the in-situ condition to design. The consolidation properties of soft clay layers changing the size of the cell are investigated by large-scale consolidation test apparatus and the behaviors of self-weight consolidation are predicted by numerical analysis.

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Lexical Discovery and Consolidation Strategies of Proficient and Less Proficient EFL Vocational High School Learners

  • Chon, Yuah Vicky;Kim, You-Hee
    • English Language & Literature Teaching
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    • v.17 no.3
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    • pp.27-56
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    • 2011
  • The analysis on the use of lexical discovery and consolidation strategies that have been researched within the area of vocabulary learning strategies (VLS) have not sufficiently drawn the interest of EFL practitioners with regard to vocational high school learners. The results, however, are expected to have implications for the design of vocabulary tasks and instructional materials for EFL learners. The present study investigates EFL vocational high school learners' use of lexical discovery and consolidation strategies with questionnaires, where the use of the learners' lexical discovery strategies were further validated with the think-aloud methodology by asking samples of proficient and less proficient learners to report on their reading process while reading L2 texts that had not been exposed to the learners. The results indicated that there were significant differences between the two groups of learners in the employment of 11 of the strategies which were in the categories of determination, social, memory, and metacognitive strategies, but not for cognitive strategies. The pattern of strategies indicated that different lexical discovery and consolidation strategies were employed relatively more by one proficiency group than another. The study suggests some implications for how strategy-based instruction can be implemented in EFL classrooms.

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Website Color for Brand Image Consolidation

  • Kim Soo-Jeoung;Huh Joo-Hee
    • Archives of design research
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    • v.19 no.3 s.65
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    • pp.31-44
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    • 2006
  • With 'the improvement of brand image through the consolidation of the online and offline brand images' as the goal, the focus of this study lies in brand color. In order to analyze the differences between the website and offline image of a brand, as felt by the consumers, a survey on color image was conducted. Using the results of the survey as the foundation, a comparative analysis of online and offline color images was conducted, and the discrepancies between the two specified. Furthermore, solutions in creating websites that cultivate brand consolidation through color consolidation are presented. Using the thesis 'Research on the Color Strategy of Brand-name Coffees,' as a guide, and supplementing it with necessary improvements, this study presents three areas to consider when designing or managing websites for offline brands. First of all, color image is not static but variable, meaning that it appeals to the consumers differently, depending on change in other brands, trends, consumer point of view, etc. Thus, color image must be flexible. Secondly, overall brand image can be improved by its offline color. However, it should be realized that identical colors could produce different results online and off. Lastly, in general, the online image falls behind the offline image, in regard to color strategy. Therefore, more meticulous and carefully planned color design is necessary, as is the consideration of the unique and distinctive qualities of the World Wide Web.

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A Study on Consolidation Characteristics by Considering the Initial Radial Compression at Sand Pile Adjacent Ground (샌드파일 주변지반에서 초기 방사방향 압축에 의한 압밀특성 연구)

  • 천병식;여유현
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.649-656
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    • 2000
  • Consolidation of the ground surrounding the sand piles is delayed by well resistance and smear effect. This study is executed to understand the factors that affect the characteristics of consolidation. This was accomplished by utilizing the estimated and measured values of the soil properties through the monitoring of the ground surrounding the sand piles. When it is assumed that the horizontal coefficient is equal to the vertical coefficient of consolidation, the estimated values is exceedingly similar to the measured values. The properties of the initially disturbed soil by the sand pile installation seemed to improve through the process of consolidation with the passage of time. From the results of the analysis of the settlement measurement, the measured values occurred about 60~90% of the predicted values. Considering the initial radical compression deformation, according to the theory of cavity expansion, the difference between the two appears to be in good agreement. In this study, to understand the behavioral characteristics of the ground surrounding the sand piles requires estimation through considering the initial radial compression as well as smear effect of the soil disturbance and well resistance.

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Undrained Shear Strength of Clay and Stability of Sub]marine Slope Undergoing Rapid Deposition (점토의 비배수 전단강도와 지적성퇴적에 의한 해저사면의 안정성)

  • 김승열
    • Geotechnical Engineering
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    • v.4 no.4
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    • pp.5-18
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    • 1988
  • A series of CU triaxial compression tests were conducted to investigate the variation of -untrained shear strength of underconsolidated clay at different degrees of consolidation. The soil samples were artificially made by one-dimensional consolidation using soft Bangkok Clay. The test results showed that the undrained shear strength of clay parabolically increased convoking downward with increasing degrees of consolidation. However, all the measured shear strength were unanimously related to the effective stress. These experimental results were used in the numerical analysis. A finite element computer program was developed to investigate the stability of submarine .slope undergoing rapid deposition taking into account the variation in soil compressibility and permeability during the consolidation process. The relationships of degree of consolidation with time as a function of rate of deposition and angle of slope were established. A method of predicting the time of slope failure and the volume of moving mass of soil was also made.

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Prediction of Final Settlement on Soft Ground (연약지반에서 최종침하량의 예측방법)

  • 임성훈;강예묵;이달원;김지훈
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1998.10a
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    • pp.449-454
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    • 1998
  • This study was performed of the research for accurate prediction of consolidation settlement at initial consolidation time. In order to analysis the program is developed which is able to analysis behavior of settlement caused by gradual load increment, and simulated consolidation using whole measured settlement data and that from beginning of embankment to end of it. The former result agrees with measured data and the latter it overestimated 13% larger than measured data. It was found the time which takes to be eliminated effect of gradual step load. This method is compared with the results from Asaoka, Hyperbolic and Tan's hyperbolic method respectively Asaoka and Tan's hyperbolic methods we in good agreement with this method. But classical hyperbolic method overestimated about 32%.

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Applicability of Cross Shaped Drain to Soft Clay Improvement (십자형 연직배수재의 점성토지반 개량에의 적용성)

  • 장연수;김영우;김수삼
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.09a
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    • pp.9-16
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    • 2000
  • Applicability of the cross shaped drain in a soft clay ground is examined using the laboratory discharge capacity test, column consolidation test and 3-D numerical flow analysis. The equivalent diameter of the tested drains is back-calculated from the laboratory experiment and compared with those calculated from the formula suggested in the literature. The effective range of the cross shaped drain about the discharge capacity and coefficient of permeability is analyzed. The results of numerical analysis show that the cross shaped drain which has a cross-sectional area twice of the band shaped drain can reduce the consolidation time by 30% from that for the band shaped drain in a soft clay ground that K is over 1${\times}$10$\^$-7/cm/sec

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