• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.2
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• pp.67-76
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• 2017

In this study, the effect of caisson heel on the active earth pressure is investigated. Using limit analysis method, inclinations of slip surface developed above the heel with different lengths are analyzed. The shorter the heel length, the larger those of inside slip surface, however those of outside slip surface are not changed. According to the relative heel length, relationships of internal friction angle of backfill material - wall friction angle between caisson structure and backfill - friction angle acting on virtual section at the end of heel are presented. Earth pressures acting against caisson structure with relatively short heel are smaller than Rankine earth pressure but always greater than Coulomb earth pressure which does not consider the heel length.

• Journal of the Korean Geosynthetics Society
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• v.14 no.2
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• pp.23-33
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• 2015

The earth pressure acting on underground structure was measured by application of the instrumentation system in the subway construction site constructed by the method of cut-and-cover tunnel. The measured earth pressure was compared with the earth pressure obtained from the existed theoretical equation, and the actual earth pressure diagram acting on the underground structure was investigated. As a result of investigation, the vertical earth pressure is mainly affected by the embankment height, and the lateral earth pressure is significantly affected by whether the existence of earth retaining structures or not. The measured vertical earth pressure is very similar to the theoretical earth pressure proposed by Bierbaumer. The measured lateral earth pressure is closed to the active earth pressure proposed by Rankine rather than the earth pressure at rest. The coefficient of earth pressure in soil deposit layer is about 0.35, and the coefficient in soft rock deposit layer is about 0.21. For design and construction the underground structures, therefore, it is reasonable estimation that the lateral earth pressure acting on structures installed in soil deposit layers is an average value between active earth pressure and earth pressure at rest. In rock deposit layers, the lateral earth pressure acting on structure is an active earth pressure only.

• Journal of the Korean Geotechnical Society
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• v.20 no.4
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• pp.75-88
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• 2004

It is known that the earth pressure acting on the cylindrical retaining wall in cohesionless soils is small than that acting on the retaining wall in plane strain condition due to three dimensional arching effect. In this study, the earth pressure equation considering the earth pressure decrease by horizontal and vertical arching effects, overburden, wall friction, and failure surface slope is proposed. For the purpose of verifying the applicability of proposed equation, model test is performed with apparatuses that can control wall displacement, wall friction, and wall shape ratio. Influence of each factor on the active earth pressure acting on the cylindrical retaining wall is analyzed according to the model test in constant wall displacement condition. The comparison of calculated results with measured values shows that the proposed equations satisfactorily predict the earth pressure distribution on the cylindrical retaining wall.

• 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 GEO-environmental Society
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• v.7 no.4
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• pp.15-24
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• 2006

It is well known that earth pressure on the cylindrical open caisson and cylindrical retaining wall of a shaft is less than that at-rest and in plane strain condition because of the horizontal and vertical arching effects due to wall displacement and stress relief. In order to examine the earth pressure distribution of a cylindrical wall, model tests were performed in dry sand for the care of constant wall displacement with depth. Model test apparatus which can control wall displacement, wall friction, and wall shape ratio was developed. The effects of various factors that influence earth pressure acting on the cylindrical retaining wall of a shaft were investigated.

• Geotechnical Engineering
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• v.14 no.5
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• pp.17-28
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• 1998

The design of a ground anchor wall calculating the design anchor force and anchored walls depends primarily on the earth pressure acting on anchored w deflection of the wall, the wall stiffness, distribution exists for anchored walls. In the apparent earth pressure envelope design of anchored walls. In this study, full scale anchored w pressure distribution was obtained from function. Earth pressures obtained from pressure and with the apparent earth pre the anchored wall in sand. It is conclude is appropriate for the anchored wall design.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.175-187
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• 2003

The earth pressure acting on the cylindrical retaining wall in cohesionless soils is different from that on the retaining wall in plane strain condition due to three dimensional arching effect. Accurate estimation of earth pressure is required for the design of vertical cylindrical retaining wall. Failure modes of the ground behind vertical shaft are dependent on ground in-situ stress conditions. Failure modes are actually divided into two modes of cylindrical failure mode and funnel-shaped mode with truncated cone surface. Several researchers have attempted to estimate the earth pressure on cylindrical wall for each failure mode, but they have some limitations. In this paper, several equations for estimating the earth pressure on cylindrical wall in cohesionless soils are investigated and new formulations for two failure modes are suggested. It rationally takes into account the overburden pressure, wall friction, and force equilibriums on sliding surface.

• Journal of the Korean Geotechnical Society
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• v.25 no.1
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• pp.21-29
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• 2009

On plane strain condition, many researchers have investigated the earth pressure according to the shape of wall, and standardized method has been applied to the design of the retaining wall. But on cylindrical diaphragm wall, at-rest earth pressure has been generally used. Even though this method is on conservative side, it may lead to over-design. In this paper, the application of convergence confinement method to the calculation of the earth pressure acting on the cylindrical diaphragm wall of a shaft was suggested. In addition, a model test was carried out to investigate the distributions of earth pressure. Model test results show that the earth pressures of diaphragm wall are about 1.4 times larger than active earth pressure and about 0.8 times less than at-rest earth pressure.

• 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.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.