• Geotechnical Engineering
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• v.6 no.2
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• pp.35-46
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• 1990

An analytical solution method is described to estimate the developed static and dynamic horizontal earth pressures behind a vertical or inclined rigid wall experiencing outward toranslational movement. The results predicted by the developed method of analysis are compared with chose from the experimental model testg on sandy. The comparisons show good agreements at various stases of wall movement. When the wall i9 inclined with a certain angle in the direction of the supported strand sass, the effects of reduction in developed static and dynamic horizontal earth pressures are also analyzed. Finally, results of analytical parametric study are presented to demonstrate the effects of various parameters, such as wall friction angle and internal strand friction angle.

• International Journal of Highway Engineering
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• v.10 no.1
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• pp.41-48
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• 2008

This paper deals with the characteristics of earth pressure to the debris-fall prevention walls which usually are installed in front of steep slope. Such walls have narrow backfill width where the active soil wedge can not be developed fully. The earth pressure to such walls ue affected by the movement of wall and arching effects due to the friction developing on the surface of adjacent ground slope and wall and therefore cannot be analyzed and calculated reliably. The study is carried out through laboratory model tests using centrifuge test. Test results reveal that the earth pressure to the debris-fall prevention wall depends largely on the inclination angle of the ground slope and the wall movement. The earth pressure reduction due to wall movement was observed at the upper half of wall, while the arching effect was significant at the lower half especially in the case of steep ground slope. It can be said that from the result of this study in the design of a debris-fall prevention wall the earth pressure should be determined considering the inclination of ground slope and the condition of wall movement during and after construction.

• Journal of the Korean Geotechnical Society
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• v.17 no.3
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• pp.83-94
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• 2001

본 연구에서는 상.하단으로 구분된 2개의 동일한 보강토옹벽에 대해서 상호 이격거리에 따른 수치해석을 수행하여 전면벽체의 수평변위, 전면벽체 배면의 수평토압, 보강토체 배면의 수평토압 그리고 보강재의 최대인장력 분포 및 크기변화 양상 등 다단식 보강토옹벽의 거동을 살펴보았다. 또한, 하단 옹벽에 증가되는 응력을 산정하고자 중첩의 원리를 적용한 2:1 응력분포법을 제시하였다. 수치해석 결과 이격거리가 증가함에 따라 상단옹벽이 하단옹벽에 미치는 영향이 감소하였으며 하단 옹벽 높이의 두배 이상 이격시, 상호 거동은 독립옹벽으로 거동하였다. 하단 옹벽내 응력 산정방법에 있어서 NCMA의 방법이 가장 보수적인 결과를 보였으며 본 연구에서 제시한 2:1 응력분포법중 주동파괴면을 고려하지 않은 방법이 수치해석 결과와 가장 유사하게 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.2
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• pp.65-76
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• 1991

A numerical solution method for the evaluation of the static and dynamic horizontal active thrusts exerted by a backfill, consisting of two or three layers of different properties, on a retaining wall is proposed in the present study based on the Mononobe-Okabe analysis. Using the proposed method, the efficient type in forming a backfill with two layers of different properties is analyzed. In addition, for the design examples of a backfill made up of two or three layers of different properties, the static and dynamic horizontal active thrusts computed using the soil property of each layer are compared with those obtained from the proposed method, and also the problems expected in design are presented based on the comparisons.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1107-1112
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• 2004

For a rigid retaining wall with rough face, 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.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.443-450
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• 2002

It is known that the distribution of the active earth pressure against a translating rigid wall is not triangular, but nonlinear, due to arching effects in the backfill. In the present paper, a new formulation for calculating the active earth pressure on a rigid retaining wall undergoing horizontal translation is proposed. It takes into account the arching effects that occur in the backfill. 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 total active earth force on the translating wall.

• Geotechnical Engineering
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• v.6 no.4
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• pp.7-18
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• 1990

To deal with the case of a rigid retaining wall built close to a stable rock face with cohesionless backfill, analytical solution methods Proposed by Spangler- Handy and Sokolovskii are modified. The modified solution methods, taking into account different friction angles along the wall and the rock face, can estimate the developed static or dynamic horizontal earth pressures behind vertical retaining walls experiencing various types of outward wall movements. The range of application of each proposed method, which is represented by the ratio of the distance between the wall and the rock face to the height of the wall, is compared with each other and also is examined for different wall friction angles as well as soil friction angles. Further, the result predicted by the modified Spangler - Handy solution method is compared with that from the experimental model test on sand. The comparison shows in general good agreements at various stages of retaining wall rotation about its toe. Finally results of analytical parametric study, together with the design charts, are presented to demonstrate the effects of wall friction angles and horizontal acceleration coefficients.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.267-281
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• 2015

The ground movement and changes in earth pressure due to the consecutive construction of retaining wall and underground space were studied experimentally. A soil tank having 160 cm in length and 120 cm in height, was manufactured to simulate the vertical excavation like retaining wall by using 10 separated right side walls and underground space excavation like tunnel by using 5 separated bottom walls. The variation of earth pressure and surface settlement were measured according to the excavation stages. The results showed that the decrease of earth pressure due to the wall movement can cause the increase of earth pressure of the neighboring walls proving the arching effect. Experiments simulating continuous construction sequence also identified arching effect, however only 50% of earth pressure was restored on the 10th right side wall due to the movement of 1st bottom side wall unusually.

• Journal of the Korean Geotechnical Society
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• v.29 no.4
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• pp.33-44
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• 2013

Mononobe-Okabe (M-O) theory is widely used for evaluating seismic earth pressure of retaining wall. It was originally developed for gravity walls, which have rigid behavior, retaining cohesionless backfill materials. However, it is used for cantilever retaining wall on the various foundation conditions. Considering only inertial force of the soil wedge as a dynamic force in the M-O method, inertial force of the wall does not take into account the effect on the dynamic earth pressure. This paper presents the theoretical background for the calculation of the dynamic earth pressure of retaining wall during earthquakes, and the current research trends are organized. Besides, the discrepancies between real seismic behavior and M-O method for inverted T-shape retaining wall with 5.4m height subjected to earthquake motions were evaluated using dynamic centrifuge test. From previous studies, it was found that application point, distribution of dynamic earth pressure and M-O method are needed to be re-examined. Test results show that real behavior of retaining wall during an earthquake has a different phase between dynamic earth pressure and inertial force of retaining wall. Moreover, when bending moments of retaining wall reach maximum values, the measured earth pressures are lower than static earth pressures and it is considered due to inertial effects of retaining wall.

• Journal of the Korean Geotechnical Society
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• v.20 no.2
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• pp.87-96
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• 2004

Application of the soil nailing method is continuously extending in maintaining stable excavations and slopes. However, ground anchor support system occasionally may not be used because of space limitations in urban excavation sites nearby the existing structures. In this case, soil nailing system with relatively short length of nails could be efficiently adopted as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then could play important roles to reduce deformations mainly in an upper part of the nailed-soil excavation system as well as to improve local stability. In this study, a newly modified soil nailing technology named as the PSN (Pretension Soil Nailing) is developed to reduce both facing displacements and ground surface settlements in top-down excavation process as well as to increase the global stability. Up to now, the PSN system has been investigated mainly focusing on an establishment of the design procedure. In the present study, laboratory model tests are carried out to investigate the failure mechanism and behavior characteristics of the PSN system. Various results of model tests are also analyzed to provide a fundamental basis for the efficient design.