• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1379-1385
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• 2007

In domestic transitional zone design, there is regulation to prevent generation of irregular substructure behaviors that negatively influence in prevention of plasticity settlement on approach section and contact section as well as relieve overall track rigidity by reducing sectional foundation and track stiffness difference, but design guideline that considers dynamic behavior of transitional track in actual service line is very insignificant. Therefore in this study, characteristics of transitional track dynamic behaviors by substructure stiffness are researched and measured dynamic response of transitional track by substructure stiffness in order to prove correlation between substructure and track and calculate elasticity(stiffness) and track load of transitional track by using measurement and formula to provide basic information for developing design guideline considering dynamic behavior of service line transitional track.

• Journal of Korean Philosophical Society
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• v.129
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• pp.111-140
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• 2014

In this paper, the main subjects with which I deal are as follows: (1) Is Distancing Philosophy from the real ruling power a way of practical-philosophical resistance, based on social reformation as a axiological directivity of Kim Tae-Gil's ethical thought, though it is negative type of resistance? Or is it a sort of transformed value-free opportunist behavior which allows antidemocratic ruling group to coerce the people into submission, assuming an uncompromising stand seemingly? (2) Is Kim's defense argument on the opening of the course of National Ethics and the all-out activation of National Ethics education under Park's Yushin Regime derived from his own philosophical belief? Or is it brought out from the external conditions and circumstances surrounding Kim Tae-Gil which forces him to participate in the national undertaking for the settlement of the course of National Ethics in the university? The 'provisional' answers about the two subjects are as follows: (1) Kim's Distancing Philosophy is a type of practical philosophical revolt against the dictatorship power under Yushin Regime, though it is negative form of resistance. We can accept this philosophical elucidation above all by confirming the fact that the reform of reality is the main ethical trait running through his entire ethical thought system. However distancing philosophy disclose the crucial limits to allow itself to boil to the philosophical practice compromising with real ruling power eventually, though it is intended upon its own social ethical directivity and conviction. (2) The primary factor which affects Kim to propose such an advocation argument on the course of National Ethics and the education of National Ethics is the external conditions and circumstances surrounding him, especially the power-relation between he and ruling group and intimate human relation between he and his superior philosophers who carries out the role of a ideologue for the Yushin Regime, rather than his own philosophical belief. But no matter what primary factor, Kim's action to make a advocating argument to support the course and the education of National Ethics is to blame, on that account that he cannot adequately his social responsibility and role given to him as a reformist moral philosopher who will pursue the realization of righteous democratic society. Along with that, It is not too enough to criticize him sharply for such defending action. The reason is that his supporting stance for National Ethics education is brought out, by not adhering closely to the philosophical way of distancing from the dictatorial power devoid of political legitimacy and moral justification.

• Geotechnical Engineering
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• v.7 no.3
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• pp.51-64
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• 1991

The reliable estimation of pile bearing capacity is essential for the improvement of the re- liability and the cost-effectiveness of the design. There have been numerous pile bearing capacity prediction methods proposed up to now, however, execpt for the estimation made from the result of the pile loading test, not one method is appropriate for the reliable prediction. Due to the considerable time and expenses required to carry out the pile loading test, the test has seldom been utilized. The development of Simple Pile Loading Test(SPLT) which utilizes the pile skin friction as the required reaction force to cause the pile tip settlement, provides a solution to perform more pile loading tests and consequently a more economical pile design is possible. The separate measurement of skin friction and tip resistance during the course of performing SPLT provides a better understanding of the pile behavior than the result of the conventional pile loading test where only the total resistance is measured. On the other hand, there are some points to be clarified in order to apply the test results of SPLT to practical problem. They are the direction of the applied load to mobilize the skin friction and the use of reduced sized sliding core. In this research, both the SPLT and the conventional pile loading test on 406mm diameter steel pipe pile have been performed. From the result, it would be safe to use the measured SPLT skin friction value directly in the design, since the value is somewhat lower than the value measured in the conventional test. It is further assumed that the tip resistance value of the reduced sized sliding core should properly be analysed by taking the incluonce of scale effect into consideration.

• The Journal of Engineering Geology
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• v.24 no.2
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• pp.227-235
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• 2014

The deformation modulus is one of the essential factors in determining ground behavior and safety during tunnel excavation. In this study, we conducted a back-analysis using crown settlements measured during tunnel excavation, using a horizontal inclinometer on a fault zone of pegmatite, and calculated the deformation modulus of the fault zone. This deformation modulus calculation was then compared with deformation moduli found through established relationships that use the correlation between RMR and the deformation modulus, as well as the results of pressure-meter tests. The deformation moduli calculated by back-analysis differs significantly from the deformation moduli determined through established relationships, as well as the results from pressure-meter tests conducted across the study area. Furthermore, the maximum crown settlements derived from numerical analysis conducted by applying deformation moduli determined by these established relationships and the pressure-meter tests produced noticeable differences. This result indicates that in the case of a weak rock mass, such as a fault zone, it is inappropriate to estimate the deformation modulus using preexisting relationships, and caution must be taken when considering the geological and geotechnical characteristics of weak rock.

• Journal of the Korean GEO-environmental Society
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• v.13 no.7
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• pp.19-29
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• 2012

For foundation of Port structure, it is essential geotechnical understanding about feature of ground and the geologic formation which is different to terrestrial ground. What is most important is the understanding of soft ground clay, which is much softer than terrestrial ground. To build foundation of a port structure which is mainly gravity based on the special geographical circumstance that is on the sea, the improvement method of foundation should be applied according to soft clay ground features. Therefore, in this study, the behaviors of improved materials with strength were analyzed on the soft clay foundation where suppose to be located the foundation of port structure. The laboratory model test has been conducted in 2 cases with unconfined compression strength of improved materials, 25kPa and 125kPa. Cement, water, and in-situ soft clay were combined at a fixed rate and made a shape of 5cm diameter ${\times}$ 70cm height column. Improved materials were located with replacement ratio(11%, 35% and 61%) in 38cm diameter ${\times}$ 80cm height cylinder. Finally, the stress distribution ratio on the improved materials and clay, settlement was analyzed by applying a load of 10kPa, 30kPa, and 50kPa.

• Journal of the Korean GEO-environmental Society
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• v.15 no.1
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• pp.53-62
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• 2014

In Korea, in general, separation distance between existing parallel tunnels was set at two to five times as distant as the diameter of the tunnels according to ground conditions. Recently, however, actual applicability of closely spaced parallel tunnels whose distance between tunnel centers was shorter than the diameter has increased due to environmental damages resulting from massive cutting, restriction in purchase of required land, and maintenance of linear continuity. In particular, when the pillar width of tunnel decreases, the safety of pillars affects behaviors of the tunnel and therefore the need for diverse relevant studies has emerged. However, research so far has been largely confined to analysis of behavior characteristics of pillars, or parameters affecting design, and actually applicable and quantitative data have not been presented. Accordingly, in order to present a stability evaluation method which may maximally reflect construction conditions of spots, this study reflected topographical and stratigraphic characteristics of the portal part with the highest closeness between the tunnels, simulated multi-layer conditions with rock mass and complete weathering, and assessed the degree of effect the stability of pillars had on the entire tunnels through numerical analysis according to changes in pillar width by ground strength. This study also presented composite analysis result on ground surface settlement rates, interference volume rates, and average strength to stress and a formula, which may be applicable to actual work, to evaluate safety rates of closely spaced parallel tunnel pillars and minimum pillar width by ground strength based on failure criteria by Hoek-Brown (1980).

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.1-13
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• 2019

The purpose of this study is to examine the effect of soft ground improvement by dynamic replacement with utilizing crushed rock. In order to understand the ground improvement effect when applying dynamic replacement method with crushed rock, the laboratory test and field test were performed. The internal friction angle and apparent cohesion were derived through direct shear test. The dynamic replacement characteristics were identified by analyzing the weight, drop, and number of blows needed for dynamic replacement. Through the field plate bearing test and density test, the bearing capacity and settlement of the improved ground were measured, and the numerical analysis were conducted to analyze the behavior of the improved ground. In this study, it proposes modified soil experimental coefficient(C_DR) to 0.3~0.5 in the dynamic replacement method with crushed rock. Also when applying the dynamic replacement method using crushed rock, the particle size range is less than 100 mm, D₉₀ is less than 80 mm and D₁₅ is more than 30 mm.

• Journal of the Korean Society of Food Culture
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• v.19 no.3
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• pp.295-312
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• 2004

This study is to investigate the trend of researches on food and culture from 1990 to 2003. With a literary approach, this paper analyzes how many papers were published and what was the major research subject. We classified the journals published during this time into 10 different categories and we are to grasp a research trend. 1) Historical approach on the traditional food and food habit; 2) Globalization of Koran food; 3) Use and preparation for traditional food; 4) Table setting and table manner; 5) Provincial cuisine; 6) Traditional festive food or celebratory meal; 7) Religious food; 8) Fusion food; 9) Food and culture in foreign countries and food habit of Korean people living abroad; 10) Studies related with satins out. It was revealed that 268 papers(=ps) were published. Eating out was the most frequently reported subject(100 ps), followed by provincial cuisine(54 ps), use and preparation for traditional food(49 ps), food habit for foreign people and Korean people living abroad(22 ps). Researches on these 4 topics have been accelerated since the late half of 1990s. This reflects the social factors such as rapid growth of food service industry, settlement of local autonomy, popularization of leisure activities and accelerated introduction of foreign food and culture. Half of the studies on the eating out dealt with eating out behavior. And 30 papers were reports on the food service industry situations. More than half of the studies on the provincial cuisine(26 ps) were concentrated on digging out recipes. Studies on the use and preparation for traditional food were mainly about what kind of food and how often the food is used(17 ps). Kimchi was the most frequently studied food. There were 11 papers regarding food and culture in foreign countries. Most of the authors were historians or linguists. Food habit of Korean people living abroad were investigated in 7 papers. There was few studies on fusion food, table setting and table manner. This doesn't meet with increasing demand for specialized information in then fields. Researches on the traditional festive food or celebratory meal(5 ps) and religious food(9 ps) were negligible. Papers on the historical approach to the traditional food and food habit were limited(12 ps). Moreover, most of them were patchwork of existing literatures. Continuous researches to exploit the historical facts based on literary proof should be tried with patience. Otherwise, the papers will copy the hackneyed knowledge repeatedly. Globalization of Korean food means the development of Korean food for foreign people and export of them worldwide. Only 16 papers were reported on this subject, 14 of them were published after 2000, 8 of them were surveys on the foreigners' food preference. In order to get practical informations on what we develope and how we sell for the foreign customers, profound research on their food habit should be done.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.295-307
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• 2002

In the Nakdong River plain a very thick clayey soils are covered widely. Since the early 1990's, some huge reclamation projects have been performed for the development of industrial and residential complexes and so on. Despite a large number of soil investigations have been carried out for the projects, the geotechnical properties have never been elucidated well, so that the settlements of the ground due to the mischaracterized properties were greatly underestimated. Therefore, it has been needed to evaluate definitely the characteristics of the clayey soils, particularly for the compressibility characteristics to help understand the settlement behavior. For the compressibility characteristics of the Pusan clays, physical index and consolidation tests were conducted on the reconstituted and undisturbed samples. Using the result of physical index, the Pusan clays could be divided into two different units, which have different depositional environments. According to the concepts of Burland (1990) and Nagaraj et. al. (1990), the intrinsic state line and field compression curve of the Pusan clays could be established. It could be found from their concepts that the Pusan clays are under the cemented and young normally consolidated state and largely consisted of two units. The cementation of the clays was as well identified by compression index ratio (Tsuchida et. al.,1991) and sensitivity (Leroueil et. al.,1983).

• Tunnel and Underground Space
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• v.18 no.6
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• pp.491-502
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• 2008

A certain range of the original ground around the tunnel should be preserved to ensure structural safety of the tunnel when other structures are made around the tunnel, and thus this range is defined as safety zone of the tunnel. The main points to ensure the stability of an existing tunnel when constructing a new tunnel in an inter-crossing area are distance between two tunnels, size of the new tunnel, excavation method for the new tunnel, ground condition around the tunnel, and lining type of the existing tunnel etc. When the new tunnel is excavated above the existing tunnel, the existing tunnel is likely to suffer deformation at a crown zone, damage of arching effect, and live load of the new tunnel etc. On the other hand, when the new tunnel is excavated below the existing tunnel, the existing tunnel is likely to be damaged due to settlement. This study has been made on the behavior of the existing tunnel by means of model test and numerical analysis when the new tunnel is excavated below the existing tunnel. Safety zone of the tunnel was estimated by the results of strength/stress ratio obtained from numerical analysis, and the movement of ground was estimated by the model test. The results of earth pressure, ground displacements, and convergence of the tunnel obtained from model test were compared with those of numerical analysis, and show a similar trend.