• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.181-191
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• 2004

For a rigid retaining wall with rough face, the magnitude and distribution of active earth pressure on the wall are affected by the shape of failure surface and arching effect developed in the backfill as well as internal friction angle of the backfill and wall friction angle. Therefore, the practical shape of failure surface and arching effect in the backfill must be considered to acquire accurate magnitude and non-linear distribution of active earth pressure acting on the rigid retaining wall. In this study, a new formulation for calculating the active earth pressure on a rough rigid retaining wall rotating about the top is proposed considering the practical shape of non-linear failure surface and arching effects. Accuracy of the proposed equation is checked through comparisons of calculations from the proposed equations with existing model test results. The comparisons show that the proposed equations produce satisfactory results.

• Journal of Sasang Constitutional Medicine
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• v.8 no.1
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• pp.319-335
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• 1996

연구 목적 : 복지부 발표 '1993년도 대한민국 국민들의 영양상태'보고서를 보면 1인당 섭취열량은 1969보다 257Kcal가 줄어든 것으로 나타났다. 그런데도 불구하고 일부의 사람들은 과도한 열량을 섭취하고 있기 때문에 비만인 사람이 점점 늘어나고 있다. 그렇다보니 신문이나 잡지에서는 거의 매일 살빼는 약이나 신종 다이어트방법에 대한 광고와 기사를 앞다투어 내보내고 있는 실정이다. 비만증은 근래에 발병률이 현저히 증가하면서 중풍, 당뇨병, 고혈압, 암, 간경화증, 당석증 등의 만성질환의 이환율을 증가시키고, 관절에 큰 부담을 주어 골관절염을 보다 빠르게 진전시키며, 사람들의 수명을 단축시키는 등 심각한 건강상의 문제를 일으키고 있다. 또한 비만증은 용모의 손상을 일으켜 정신적인 스트레스의 주요 인자로 등장하고 있기도 하다. 비만인이 증가하는 원인으로는 서구화된 음식습관으로 동물성 지방질과 단백질의 섭취증가, TV 자동차 세탁기 오디오 리모콘 등 생활이기의 사용으로 인한 운동부족, 체질과 질병 등이 재기되고 있다. 이제까지 비만을 치료하기 위한 많은 시도가 있었으나 주된 이론은 섭취음식의 절재와 운동량을 증가시키는 것이었으며, 체질적인 요소를 중심으로 비만증을 해결하려는 시도는 없었다. 이에 저자는 1992년 8월 20일부터 1995년 8월 19일까지 만 3년동안 상지대학교 부속한방병원 체질의학과에서 치료받는 461명의 환자를 대상으로 사상체질과 비만과의 상관성을 임상적으로 연구하고 그 효과를 보고하는 바이다. 연구 결론 : 상지대학교 부속한방병원에 내원치료를 받고 있는 비만증환자들을 대상으로하여 체질과 비만과의 관계를 연구한 결과는 다음과 같다. 1. 비만증 환자의 70.2%가 태음인이었다. 2. 치료결과 4주동안에는 $1.48{\pm}1.64kg$, 5주부터 8주동안에는 $2.05{\pm}2.10kg$, 9주부터 12주동안에는 $2.18{\pm}2.27kg$, 13주부터 16주동안에는 $2.08{\pm}2.88kg$이 감량되었다. 3. 체중감량에 있어 태음인이 가장 많은 감소를 보였다. 연령별로는 10대에서 가장 많은 감소를 보였다. 4. 비만환자의 혈액 가운데 총 콜레스테롤, 저밀도 지방단백이 높온 사람보다 유리지방산과 중성지방이 높은 경우가 대부분을 차지했다. 5. 비만인의 혈청지질에서는 FFA, TG가 높았다. 그 이유는 육식보다는 당질과 지방질의 섭취로 나타난 것이었다.

• Geotechnical Engineering
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• v.4 no.1
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• pp.7-16
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• 1988

The safety factor has been used widely and uniquely at present to check the safety of the structure . However, probability of failure would be logically attempted to check the reliability of the structure in future Coulomb's theory or Rankine's theory has been applied in practice to retaining earth structure in spite of the fact that the lateral earth pressure, which is the primary factor in the determination of wall structure, depends on the modes of wall movement . This study is concentrated on the two modes of , wall movement (active case rotation about bottom(AB) , active case rotation about top(AT)) of the overturning'failure of vertical wall with horizontal sand backfill . The static active earth pressure is determined by applying each of Coulomb's theory, Dubrova's redistribution theory and Chang's method The earthquake active earth pressure is determined by adding Seed and Whitman's earthquake pressure to the static earth pressure , On the condition that design variables are fixed with each of the above earth pressure, reliability is analyzed using the recently developed method of AFOSM (Advanced First Order Second Moment)

• Geotechnical Engineering
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• v.2 no.3
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• pp.27-36
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• 1986

To investigate the seepage effect on the compacted backfill of retaining walls, an expriment and an analytical study were carried out First, the expriment was performed with a two-way permeameter newly designed for the do- termination on the degree of permeability anisotropy of compacted soils. As a result, e-log(kz/ky) plot showed a linear relationship, where kz and ky were permeability coefficients for the normal and the parallel directions to the compaction. The degree of permeability anisotropy, kz/ky was 2 to 4 at Dr>90% for sands, regardless of the methods of compaction. The kz/ky of the fine sand was greater than that of the coarse sand. Second, the exprimental results were applied to the extention of Gray's theory for the investigation of the active thrust affected by the seepage of permeability anisotropy. The active thrust was decreased with the increase in the degree of permeability anisotropy, and it It.as a little effect on wall friction.

• Journal of the Korean GEO-environmental Society
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• v.20 no.12
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• pp.15-26
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• 2019

This study was conducted to characterize shearing strength of geotextile bag, connecting materials and gabion. A largescale shaking take tests were conducted to assess kinetic characteristics of gabion-geotextile bag retaining wall. Based on the results of large-scale shaking table test, dynamic characteristics of gabion-geotextile bag retaining wall structure against acceleration, displacement, and earth pressure were also analyzed. The increments of dynamic active earth pressure were determined to be (0.376-0.377)H at 1:0.3 slope and $(0.154-0.44)g_n$ earthquake acceleration, and (0.389-0.393)H at 1:1 slope, suggesting that the increments tend to rise as the slope decreases.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.2
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• pp.3-11
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• 2018

Korea has achieved a rapid economic development and with the increase in population and national income and the expansion of social and economic activities, energy consumption has rapidly increased too. Energy consumption per head has constantly increased and currently, power consumption per head is 7.5 times bigger than in 1985. Buildings occupy 25% of total energy consumption and especially, 50% of total energy is consumed for heating and cooling. In this situation, multi-family housing, which has constantly been increased, has an energy saving rate of 1.9%, which is the lowest level and this makes the government's energy policy for sustainable energy system development useless. Besides, energy consumption leads to secondary problems, such as air, water and marine pollution and heat pollution and wastewater/drainage and the increased use of fossil fuel is a fundamental reason for ozone layer destruction and global warming. Therefore, efficient energy consumption plans are required. This study aims to analyze energy performance in each block type of high-rise and diversified multi-family housing that accounts for 60% of all the housing forms, depending on the variations in stories through BIM-based energy simulation. For this study, four representative block types were selected, based on the multi-family floor plan, which is certified for energy performance evaluation and they were applied to the floor plan of a multi-family house that is scheduled to be built. Then BIM modeling was conducted from the fifth story to the 40th story at an intervals of 5 stories and based on the finding, energy characteristics of each block type and energy performance depending on the variations in stories were analyzed. It is considered that this would serve as objective data for block type and block story decision of energy performance-based multi-family housing.

• Journal of the Korean Geotechnical Society
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• v.22 no.2
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• pp.29-39
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• 2006

In the companion paper (Paik 2006), a new formulation for calculating the nonlinearly distributed active earth pressure acting on a caisson backfilled with crushed rock and sand is proposed, and it takes into account arching effects as well as difference in internal friction angles and unit weights between sand and crushed rock. In this study, in order to partially check the accuracy of the proposed equation, the results of the proposed equation are compared with the equation proposed by Paik (2003a) for caissons with rough surface and homogeneous backfill, and are compared with results of Rankine's theory for caissons with smooth surface and homogeneous backfill. In addition, a parametric study is performed to investigate the effect of $phi_{r}$, $phi_{s}$, $\delta_{r}$, $\gamma_{r}$, $\gamma_{s}$ and $\beta$ on the magnitude of active earth pressure acting on the caisson, and construction methods for minimizing active earth pressure on the caisson are also provided based on the results of a parametric study.

• Geotechnical Engineering
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• v.4 no.2
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• pp.25-32
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• 1988

This paper first presents the distributions of static lateral earth pressure in case of translational o.all movement (ATRA) , obtained respectively by the Dubrova method and by the method where Chang's idea is applied to the former, acting on the rigid retaining vertical wall with horizontal sand backfill. Total active resultant forces and the points of application of those forces, calculated results by the two methods, are compared with the experimental results recently published by Fang Y.S. and Ishibashi I. A comparative study about the distribution of static lateral earth pressurein each case of rotation about top(AT) and base (AB), on which the writer studied previously, is also conducted along with the above experimental results. The following results are obtained 1) In case of AT and ATRA, the experimental results are in good agreement with the calculated results by the Dubrova's method. 2) In case of AB, the results of the Dubrova's method are very inconsistent with those of model test, where as th method 9.here Chang's idea is applied, corresponds well, even though there is a small deviation.

• Geotechnical Engineering
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• v.3 no.3
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• pp.21-30
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• 1987

Some methods are presented to estimate the ultimate lateral resistance of single active piles subjected to lateral loads above the ground surface, considering the lateral soil reaction, the pile length and the fixity condition of a pile head. The lateral soil reaction acting on a single active pile embedded in soil due to pile movement can be estimated by use of a theoretical equation which is derived by considering especially the plastic state of ground surrounding the pile and the pile- section shape. The piles are named short or long depending upon the relative magnitude of the induced bending moment to the yielding moment. As for the fixity condition of a pile head, the free head and the unrotated head are considered. Comparison with other experimental results gives that the calculated ultimate lateral resistance obtained by the author's theory is closer to experimental results than the one obtained by Brom's theory.

• Cement Symposium
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• no.32
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• pp.222-227
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• 2005