• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.2
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• pp.143-155
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• 2007

The earth pressure acting on a circular shaft wall is smaller than that acting on the wall in plane strain condition due to the three dimensional axi-symmetric arching effect. Accurate estimation of the earth pressure is required for the design of the shaft wall. In this study, the stress model considering the decrease of earth pressure due to the horizontal and vertical arching effect and the influence of shape ratio (shaft height/radius) is proposed. In addition, model test on the sandy soil is conducted and a comparison is made between the stress model and the test results. The comparison shows that the proposed stress model is in agreement with test results; decrease of shape ratio (increase of radius) leads to stress state equal to the plane strain condition and approximate stress distribution is found between stress model and model test results.

• Journal of the Korean Geotechnical Society
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• v.31 no.10
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• pp.49-60
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• 2015

Since previous studies on the 3-dimensional earth pressure have been conducted focusing on the stability of wall, it is very difficult to find a study on the load transfer to the adjacent ground induced by the 3-dimensional active displacement. Therefore, in this study, we tried to find out the load transfer to the adjacent ground induced by the 3-dimensional active displacement depending on the size of rectangular wall which was defined by the aspect ratio, that is, the ratio of the height to the width of the wall. 3-dimensional model tests were performed in order to measure the distribution and the magnitude of load transfer to surrounding grounds. The transferred load was 17.9~30.6% less than the difference between the 3-dimensional active earth pressure and earth pressure at rest. The transferred load of both vertical and horizontal was maximum at the boundary of the active wall. The load transfer range depended on the normalized height of the active wall, and it was 0.67~1.29w in horizontal direction and 1.0~3.0h in vertical direction. The transferred load in horizontal was maximum at the height of the wall. As the aspect ratio increases the location of the maximum transferred load points becomes higher. The ratio of the transferred load area of 56~79% at 0.25w in horizontal direction and 50~58% at 1.0~1.5 in vertical direction. Diagrams showing the distribution and the magnitude of the transferred load depending on the aspect ratio were suggested.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.193-203
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• 2004

Arching effects in backfill materials generate a nonlinear active earth pressure distribution on a rigid retaining wall with rough face, and arching effects on the shape of the nonlinear earth pressure distribution depends on the mode of wall movement. Therefore, the practical shape of failure surface and arching effect in the backfill changed with the mode of wall movement must be considered to calculate accurate magnitude and distribution of active earth pressure on the rigid wall. In this study, a new formulation for calculating the active earth pressure on a rough rigid retaining wall rotating about the base is proposed by considering the shape of nonlinear failure surface and arching effects in the backfill. In order to avoid mathematical complexities in the calculation of active earth pressure, the imaginary failure surface composed of four linear surfaces is used instead of the nonlinear failure surface as failure surface of backfills. The comparisons between predictions from the proposed equations and existing model test results show that the proposed equations produce satisfactory predictions.

• Journal of the Korean Geotechnical Society
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• v.40 no.4
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• pp.19-32
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• 2024

Dynamic earth pressure analysis is a key parameter in the seismic design of subterranean structures. However, existing solutions often lack a holistic approach, ignoring crucial elements like soil-structure interaction, the relative flexibility ratio (F) between the soil and a structure, the racking ratio (R) of a structure, and the structure aspect ratio (L/H). In this study, we conducted a thorough suite of dynamic numerical analyses on basements to understand how these factors influence seismic earth pressure. We found that structures with high aspect ratios and low flexibility were more susceptible to seismic pressure than those with lower aspect ratios and greater flexibility. Consequently, we recommend taking the aspect ratio and flexibility into account when estimating the seismic or dynamic earth pressure on basements and exercising caution when using traditional solutions proposed for retaining walls.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.191-199
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• 2003

It is known that the distribution of the active earth pressure against a rigid wall is not triangular, but nonlinear, due to arching effects in the backfill. In the farmer paper, a new formulation was proposed for the nonlinear distribution of active earth pressure on a translating rigid retaining wall considering arching effects. In this paper, parametric study is performed to investigate the effect of ${\phi}, {\delta}$ and wall height on the magnitude and distribution of active earth pressure calculated from the proposed equations. In order to check the accuracy of the proposed formulation, the predictions from the equation are compared with both existing full-scale test results and values from existing equations. The comparisons between calculated and measured values show that the proposed equations satisfactorily predict both the earth pressure distribution and the lateral active earth force on the translating wall. Simplified design charts are also proposed for the modified active earth pressure coefficient and fur the height of application of the lateral active force in order to facilitate the use of the proposed equation.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.181-189
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• 2003

The active earth pressure against a rigid retaining wall has been generally calculated using either Rankine's or Coulomb's formulation. Both assume that the distribution of active earth pressure exerted against the wall is triangular. However, many experimental results show that the distribution of the active earth pressure on a rigid rough wall is nonlinear. These results do not agree with the assumption used in both Rankine's and Coulomb's theories. The nonlinearity of the active earth pressure distribution results from arching effects in the backfill. Several researchers have attempted to estimate the active earth pressure on a rigid retaining wall, considering arching effect in the backfill. Their equations, however, have some limitations. In this paper, a new formulation for calculating the active earth pressure on a rough rigid retaining wall undergoing horizontal translation is proposed. It takes into account the arching effects that occur in the backfill.

• Journal of the Korean Geotechnical Society
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• v.22 no.1
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• pp.63-72
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• 2006

Coulomb's theory has traditionally been used for the estimation of active earth pressure acting on rigid walls. However, many experimental data show that active earth pressures on rough, rigid walls are nonlinearly distributed. This is due to the arching effects produced by friction between the wall and backfill materials when the wall translates away from the backfill. Although there are analyses that take arching into consideration f3r a horizontal backfill surface and a vertical rigid wall, these analyses were derived for homogeneous backfill. Therefore, it is not possible to use these analyses for a caisson backfilled with crushed rock and sand, a common type of rigid wall for harbor structures. In this study, a new formulation for calculation of the nonlinear active earth pressure acting on a caisson backfilled with crushed rock and sand is proposed considering both internal friction angles and unit weights of the crushed rock and sand.

• Journal of the Korean Geotechnical Society
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• v.31 no.9
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• pp.69-78
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• 2015

If an active displacement occurs on a wall with finite size, the ground behind the wall forms shapes of 3-dimensional wedges and 3-dimensional active earth pressure are applied on the wall. In the previous studies, shapes of 3-dimensional wedges were measured and the resultant of 3-dimensional active earth pressure has been calculated. In this study, the magnitude and the distribution of 3-dimensional active earth pressure depending on the size of a rectangular wall, which was defined by the aspect ratio (h/w), that is, the ratio between the height and the width of wall, were measured and compared with previous 3-dimensional models. The result shows that, the horizontal displacement (S) of the wall is approx 0.12% of the height of wall (h). The resultant 3-dimensional active earth pressure is similar to that of Karstedt (1982). The distributions of earth pressures on the wall are parabolic shape. The peak earth pressure was measured at the 0.5~0.55 depth from the ground surface. The reduction factor of 3-dimensional active earth pressure against the 2-dimensional earth pressure (${\alpha}$) depending the aspect ratio (h/w) is presented by the diagram.

• 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.

• Geotechnical Engineering
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• v.13 no.4
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• pp.135-148
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• 1997

Coulomb's theory has been usually used in practice to obtain lateral earth pressure against retaining wall. Such theory is based in the assumption that the lateral pressure is a tai angular distribution, since the point of applying the lateral thrust cannot be obtained by using it. However, the results of laboratory and field tests showed that the lateral pressure was not a triangular but a nonlinear distribution. To overcome the drawback of the Coulomb's theory, the different theoretical approaches(Handy, 1985. Kingsley, 1989 : Kellogg, 1993, Chung et at,1993, 1996a) were performed for gravity wall backfilled by cohesionless soil. On the other hand, for retaining wall backfilled by ,cohesive soil, theoretical analyses were carried out only on the basis of the Rankine's or Coulomb's concepts, but the equations showed different results. Here was newly derived the equations of lateral pressures under undrained condition against gravity wall backfilled by cohesive soil. They were based on the Coulomb's wedge, adopted the arching concept. Some of the equations were derived by neglecting tension crack, while the others by considering it. Comparative results for applying different examples showed that the equation considering tension crack might be reasonable.