• Structural Engineering and Mechanics
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• v.33 no.5
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• pp.635-647
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• 2009

For the calculation of foundation settlement it is recommended to take into account so called influence zone inside the subsoil bellow the foundation structure. Influence zone inside the subsoil is the region where the load has a substantial influence on the deformation of the soil skeleton. The soil skeleton is pre-consolidated or over consolidated due to the original geostatic stress state. An excavation changes the original geostatic stress state and it creates the space for the load transferred from upper structure. The theory of elastic layer in Westergard manner is selected for the vertical stress calculation. The depth of influence zone is calculated from the equality of the original geostatic stress and the new geostatic stress due to excavation combined with the vertical stress from the upper structure. Two close formulas are presented for the influence zone calculation. Using ADINA code we carried out several numerical examples to verify the proposed analytical formulas and to enhance their use in civil engineering practice. Otherwise, the FEM code accuracy can be control.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.1
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• pp.89-96
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• 2008

The study, with regard to unsymmetrically inclined backfilled wall, was intended to estimate the lateral earth pressure, develop the equation for lateral earth pressure and eventually identify the mutual behavior, based on the modified Kellogg theory, while changing the width between the walls, wall angle, relative density and wall friction angle. To verify the geostatic pressure obtained from the study, the results in the wake of 62 kinds of model tests performed were compared and evaluated with the behaviors based on theoretical equations. As a result, the wall inclination angle was found to be the factors affecting the earth pressure the most, when both walls were inclined unsymmetrically. And the narrower the backfill space and the larger the wall inclination angle to the horizontal level, the greater the effect of the wall friction. The equation considering the wall friction reaction indicated the value, which was closer to the actually-measured earth pressure, and when the width between the warts was narrow, the arching effect appeared to be great, thereby indicating the difference between the measured earth pressure, theoretically calculated earth pressure and the geostatic pressure proved to be insignificant.

• Journal of the Korean Geotechnical Society
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• v.17 no.5
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• pp.147-155
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• 2001

좁은 되메움 공간의 벽체가 연직 또는 한쪽 벽체만이 경사진 경우 수평토압에 관한 연구는 국내외에서 상당히 진전되어 왔으나, 대칭으로 경사진 경우의 연구는 미흡한 실정이다. 본 연구는 되메움 공간의 벽체가 대칭으로 경사지고 벽체간 하부폭이 다를 때 발생되는 수평토압에 관한 거동을 구명하기 위하여 시도되었다. 이를 위하여 모형토조를 사용하여 되메움 공간의 벽체가 대칭으로 경사진 경우 벽체의 경사각, 하부폭, 벽마찰각, 상대밀도를 변화시켜 총 24종류의 모형실험을 수행하였고, 이 결과를 Kellogg(1993)제안식, 벽면경사를 고려한 수정 제안식 및 벽면마찰반력으로부터 구한 수평토압과 비교, 분석하였다. 연구 결과 벽면마찰반력을 고려한 경우 평균연직토압을 적용하였음에도 Arching 효과가 발휘된 실험결과와 가장 근소한 차이를 나타내었다.