• Tunnel and Underground Space
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• v.25 no.3
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• pp.264-274
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• 2015

In this study, the applicability of geotextile mesh soil nails on slopes was evaluated by numerical analysis to reduce environmental problems which a general soil nailing might produce and to improve its economical efficiency and construction convenience. To this end, in situ pull-out tests were conducted for both general soil nail and geotextile mesh soil nail and their pull-out characteristics were analyzed. Also, finite difference method was used to verify the suitability of numerical simulation. Parameters for nail and ground conditions were selected and sensitivity analysis was performed for the evaluation of slope stability. In addition, analysis was performed by limit equilibrium method which is widely used for slope stability analysis in practice. As a result, if the nail diameter was same, there is no big difference between geotextile mesh soil nails and general soil nails in terms of slope stability. Therefore it can be expected that geotextile mesh soil nails could be effective for slope reinforcement since they could keep a slope as stable as general soil nails and give better economical efficiency and construction convenience than general soil nails.

• Journal of the Korean GEO-environmental Society
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• v.6 no.1
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• pp.73-82
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• 2005

Generally, to evaluate a slope stability of the geosynthetic reinforced soil slope, the modified version of limit equilibrium method can be used. In most cases, resisting effects of reinforcement are dealt with considering an increased shear strength on the potential slip surface. However, it is not clear that the methods satisfy all three equilibrium equations. In this study, the new slope stability analysis method in which not only reinforcing effects of geosynthetics can be considered but also all three equilibrium equation can be satisfied is proposed. A number of illustrative examples, including published load test of large-scale reinforced retaining wall and centrifuge model tests on the geotextile reinforced soil slopes, are also analyzed. As a result, it is shown that the newly suggested method produces a relatively accurate factor of safety.

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.107-116
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• 2005

Generally, when the stability of the geosynthetic reinforced soil slopes is analyzed, the required tensile forces of each reinforcement layers are calculated from total reinforcement forces which are necessary to retain the equilibrium state of slip mass in which the slip surfaces are assumed to be a linear or bilinear. It is assumed that the reinforcement forces are increased or constant with depth. However, according to the instrumented field data and laboratory model test results, the maximum tensile strain of reinforcement in a reinforced soil slope is developed in a certain elevation, not a bottom of the slope. In the concept of reinforced soil, postulated failure surfaces are the traces of the position in which the reinforcement tensile forces are maximum in the layer, and the reinforcement tensile forces are related to the stress state on the postulated failure surface. Therefore, in this study, based on the distribution of normal stress on the slip surface, a new method for the evaluation of required tensile forces is suggested and a number of the instrumented field data are analyzed by newly suggested method. As a result, it is shown that the newly suggested method produces relatively accurate reinforcement tension forces.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.348-351
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• 1998

토목 및 건설용으로 사용되는 토목섬유 중 지오그리드는 경사와 위사 방향으로 10~100mm 크기의 aperture가 형성된 격자 구조를 갖는 것을 지칭하며 1980년대에 개발되어 토목공사에 적용되어 왔으며, 강도가 요구되는 방향으로 높은 인장강도를 지님으로써 도로의 기초 지반과 포장층의 보강, 제방과 사면의 보강 및 보강토 옹벽공사용 둥에 사용되고 있다. (중략)

• Proceedings of the Korean Geotechical Society Conference
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• 1997.11a
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• pp.75-86
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• 1997

• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.753-760
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• 2006

This paper presents the procedure and results of the numerical modelling that was carried out to investigate the stability of reinforced soil slopes under dynamic railway load. The two-dimensional explicit dynamic finite element method (ABACUS) was used to carry out the numerical analyses. To simulate the railway load, the top surface of the embankment was excited by the uniform distributed load whose frequency and magnitude was estimated by the measured railway acceleration during train passing. The embankment displacements and geogrid axial forces were analyzed to evaluate the stability of reinforced soil slopes under the dynamic train load.

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.95-105
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• 2005

Generally, a modified version of limit equilibrium method can be used to evaluate a slope stability of the geosynthetic reinforced soil slopes. In most cases, resisting effects of geosynthetic reinforcement are dealt with considering an increased shear strength on the potential slip surface. However, it is not clear that the methods satisfy all three equilibrium equations. As we know, the pattern of normal stress distribution along the slip surface is the key factor in calculating the safety factor of slopes. In this study, the new slope stability analysis method in which not only reinforcing effects of geosynthetics can be considered but also all three equilibrium equations can be satisfied was proposed with assuming the normal stress distribution along the slip surface as quadratic curve with horizontal $\chi-coordinate$. A number of illustrative examples, including published slope stability analysis examples for the reinforced and unreinforced soil slopes, loading test of large scale reinforced earth wall and centrifuge model tests on the geotextile reinforced soil slopes, were analyzed. As a result, it is shown that the newly suggested method yields a relatively accurate factor of safety for the reinforced and unreinforced soil slopes.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.95-99
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• 2001

토목섬유 (Geosynthetics) 중에서 사면, 옹벽 및 도로 보강을 위하여 사용되는 지오그리드는 고강력의 강도 및 적절한 신도가 필요하다. PP 또는 HDPE 의 지오그리드 등도 사용되고 있으나 creep성이 커서 장기적인 보강을 위해서는 사용에 제약을 받기도 하며, 열에 의한 변형이 쉬워 도로 시공시 변형이 발생할 수도 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.420-423
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• 2001

토목합성재료(Geosynthetics) 중 직포매트는 i) 분리, ii) 보강/보호 등의 기능을 가지고 있으며 연약지반 보강, 도로포장, 간척지 지반 공사 및 해안지역 LNG 저장고 공사, 폐기물 매립지의 사면 및 저면 보호재 등 기초 보강재료로 널리 이용되고 있다. 그러나 현재 토목건설공사에 사용되고 있는 직포매트용 봉합사는 타이어 코드 제조용 폴리에스테르 고강력사이며, 봉합할 경우 원통형 관입에 의한 인장신도가 커지게 되어 변형에 의한 파괴가 쉽게발생한다. (중략)

• Proceedings of the Korean Geotechical Society Conference
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• 1998.06a
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• pp.183-196
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• 1998