Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Geotechnical Society
Journal Basic Information
Journal DOI :
Korean Geotechical Society
Editor in Chief :
Volume & Issues
Volume 26, Issue 12 - Dec 2010
Volume 26, Issue 11 - Nov 2010
Volume 26, Issue 10 - Oct 2010
Volume 26, Issue 9 - Sep 2010
Volume 26, Issue 8 - Aug 2010
Volume 26, Issue 7 - Jul 2010
Volume 26, Issue 6 - Jun 2010
Volume 26, Issue 5 - May 2010
Volume 26, Issue 4 - Apr 2010
Volume 26, Issue 3 - Mar 2010
Volume 26, Issue 2 - Feb 2010
Volume 26, Issue 1 - Jan 2010
Selecting the target year
Shearing Characteristics of Aluminium Rods Using Plane Strain - Shear Box Test and Close Range Photogrammetric Technique
Lee, Yong-Joo ; Song, Ki-Jung ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 5~14
To simulate two-dimensional plane-strain conditions in the laboratory model test, the side frictional resistance between the soil and thick glass or plastic sheet of the soil container should be reduced as much as possible. However, in fact this side friction cannot be removed completely. In this paper, the ground model simulated as a multi-sized aluminium rod mixture was introduced to get rid of the side frictional resistance and applied to the laboratory shear box test. In addition, an application of the close range photogrammetric technique to the shear box test was validated. As a result, it was found that a mean value of dilation angle from the close range photogrammetry was close to the dilation angle defined by the curve of shear strain vs. volumetric strain.
Cone Resistivity Penetrometer for Detecting Thin-Layered Soils
Yoon, Hyung-Koo ; Jung, Soon-Hyuck ; Kim, Rae-Hyun ; Lee, Jong-Sub ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 15~25
The thin-layered sand seam in clay affects the soil behavior. Although the standard cone penetrometer (A:
) have been used to evaluate the thin-layered soil, the smaller diameter cone penetrometer have been commonly recommended because of the high resolution. The purpose of this study is the development and application of the Cone Resistivity Penetrometer (CRP), which detects qc, fs, and electrical resistivity at cone tip for the evaluation of thin layered soils. Two sizes of the CRP are developed for the laboratory and field test. The projected areas of CRP for the laboratory and field tests are
(d: 1.0 cm) and
(d: 1.5 cm), repectively. The length of friction sleeve is designed in consideration of ratio of the projected area to the friction sleeve area. The application tests are carried out by using the artificially prepared thin-layered soils in the laboratory. In addition, the field tests are conducted at the depth of 6 to 15 m in Kwangyang. In the laboratory test, the measured electrical resistivity and cone tip resistance detect the soil layers. Moreover, in the field test the CRP investigates the three thin-layered soils. This study suggests that the CRP may be a useful tool for detecting thin-layered in soft soils.
A Comparison of Bearing Capacity Equations for a Single Pile Considering Negative Skin Friction
Lee, Sung-June ; Jeong, Sang-Seom ; Ko, Jun-Young ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 27~37
Downdrag force develops when a pile is driven through a soil layer which will settle more than a pile. There is no obvious criterion for application of the current pile design method considering the negative skin friction. Therefore, in this study, numerical analyses were performed to investigate the behavior of a single pile subjected to negative skin friction and their results were used to determine the applicability of the current design method. Including three different sites in Song-do area and two different cases with friction pile and end bearing pile conditions, total six cases were considered. The load-settlement relationships and the neutral points were estimated for different end bearing conditions and the allowable bearing capacity of piles with negative skin friction was investigated through parametric studies. Based on the results showed that the negative skin friction made a major influence on the settlement of a pile and its stress. However the allowable bearing capacity may not be influenced by the negative skin friction. Compared with the allowable bearing capacity obtained from the ultimate bearing capacity with the safety factor of 3, the current design method with the safety factor of 3 underestimated the allowable bearing capacities regardless of the end bearing conditions. On the other hand, the current design method with the safety factor of 2 yielded reasonable results depending on the end bearing conditions.
Analysis of Mat Foundation by Considering Interface with Rock Mass
Lee, Jae-Hwan ; Cho, Jae-Yeon ; Lee, Sung-June ; Jeong, Sang-Seom ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 39~47
In recent days, the foundations of huge structures in general and mega foundations of grand bridges and high-rise buildings in particular are required in geotechnical engineering. This study described 3 dimensional behavior of mat foundation on soft rock based on a numerical study using 3D finite element method. A series of numerical analyses were performed for various soil conditions and mat rigidities under vertical loading. Based on the results of the parametric study, it is shown that the prediction of the settlement, cross sectional tensile stress and bending moments in the mat is overestimated in the analysis without considering interface behavior in comparison with the analysis considering interface between mat and rock mass.
Characteristics of 1D-Consolidation for Soft Clay Ground Based on a Elasto-Viscous Model
Baek, Won-Jin ; Ha, Sung-Ho ; Lee, Kang-Il ; Kim, Jin-Young ; Kim, Ju-Hyun ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 49~58
In this study, in order to investigate the characteristics of secondary consolidation in the soft clay ground, oedometer tests were carried out in a normally consolidated condition, and the consolidation characteristics of the soft clay ground were examined by the Finite Difference Method (FDM) based on the Elasto-Viscous model proposed by Yoshikuni. The consolidation tests adjusted the consolidation load increment ratio(
) to 1.0 for the four cases with initial consolidation pressures of 0.8, 1.6, 3.2, and 6.4 kgf/
. The long-term consolidation tests were examined by the tests that changed the load increment ratio to clarify the effect of consolidation load increment. Although the numerical analysis was delayed in the primary consolidation process, from the result of the numerical analysis of the laboratory tests, the applicability of the Elasto-Viscous model was verified from the agreement of the secondary consolidation process. Based on the developing of model ground consist of general soft clay, influences of consoliation parameters on the consolidation characteristics were studied by the numerical analysis.
Numerical Study on the Prediction of the Depth of Improvement and Vibration Effect in Dynamic Compaction Method
Lee, Jong-Hwi ; Lim, Dae-Sung ; Chun, Byung-Sik ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 59~66
In this study, an applicability by using the FEM was investigated for the prediction of both the depth of improvement and the vibration effect when dynamic compaction method is applied. The region was modelled by the field conditions applying dynamic compaction method and the rigid body force was applied to the dynamic load model. Predicted depth of improvement calculated by the vertical peak particle acceleration was compared and analyzed with an existing empirical equation, and the effect of groundwave by deducing the peak particle velocity from vibration sources was compared and analyzed with the results of another existing empirical equation. The results showed that the prediction of the depth of improvement has similar tendency to practice, and the vibration effect has some differences in a particular section from existing equation, but it could predict the safety distance to some degree. The analyzed results are expected to be basic data for the development of reliability of dynamic compaction design with existing empirical method.
A Study on the Dynamic p-y Curves in Soft Clay by 1 g Shaking Table Tests
Han, Jin-Tae ; Yoo, Min-Taek ; Choi, Jung-In ; Kim, Myoung-Mo ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 67~75
In this study, a series of 1 g shaking table tests were carried out for a single pile in soft clay with various input acceleration amplitudes and frequencies. Based on the results, dynamic p-y curves were drawn and, in turn, the dynamic p-y backbone curve was formed by connecting the peak points, corresponding to the maximum soil resistance, of the dynamic p-y curves. In order to represent the p-y backbone curve numerically, Matlock's p-y formulations for clay was used to find the initial stiffness (
) and the ultimate capacity (
) of the clay, both of which are required to formulate the p-y backbone curve as a hyperbolic function. The suggested p-y backbone curve was verified through comparisons with currently available p-y curves as well as other researchers' centrifuge test results and numerical analysis results.
Evaluation of Dynamic Group Pile Effect in Sand by 1 g Shaking Table Tests
Yang, Eui-Kyu ; Choi, Jung-In ; Han, Jin-Tae ; Kim, Myoung-Mo ;
Journal of the Korean Geotechnical Society, volume 26, issue 8, 2010, Pages 77~88
In this study, 1 g shaking table group pile tests were performed for various conditions of subgrade and pile spacing. The pile spacing was changed from three to seven times of pile diameters. It could be confirmed that the dynamic p-y curves for the group pile observed as the results of a series of shaking table tests show difference according to the pile spacing, the pile location within the pile group, the relative density of subgrade and the excess pore pressure during earthquake. The dynamic p-multipliers were calculated by comparing the dynamic p-y backbone curves of a single pile suggested by Yang (2009) and dynamic p-y curves for the group pile. Dynamic p-multiplier values overall increase as the relative density of subgrade and amplitude of input acceleration increase. The dynamic group pile effect was neglected, if the pile spacing was seven times as large as pile diameters. It was found that the exisiting p-multiplier values suggested by various researchers for the static and dynamic loading, and the values recommended by globally used specifications show difference with the test results by up to 0.7 (approximately 70%). Therefore, the dynamic p-multipliers were newly suggested according to the pile spacing and the relative density of subgrade using the test results.