• Journal of the Korean Society for Railway
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• v.3 no.2
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• pp.68-76
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• 2000

Such traditional construction methods as the interchange or improvement of railway subbase maintenance and reinforcement have many problems in the matters of construction period, constructive and economical efficiency aspects. This paper will describe the alternative railway subbase reinforcement method based on geosynthetics system. It is presently very popular in Germany and Japan. In summary it is to say, that geosynthetics used at fine grained subsoils to a strong improvement of the whole railroad system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.6
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• pp.51-60
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• 2015

This study conducted shear strength test and plate bearing test to look into the characteristics of bearing capacity using geosynthetics case on forest road surface. The shear strength test showed that the internal friction angle at the time when geosynthetics was used was measured larger on average than that in the unreinforced case. Therefore, using geosynthetics case produced more bearing capacity reinforcement effect. The result from the comparison test of internal friction angle by geosynthetics type revealed that the internal friction angle at the time when geotextile case was used was measured larger. That was attributable to the difference between the area of the total cross section of geotextile made in type of non-woven fabric and its material. Plate bearing test showed that the settlement at the time when geosynthetics was used was measured smaller than that in the unreinforced case. Therefore, using geosynthetics produced more bearing power reinforcement effect. The result from the comparison test showed that geogrid case was measured smaller than geotextile case. Henceforth, It is seemed that it will be necessary to keep studying the reinforcement engineering and process of forest road surface which fits the characteristics and conditions of geosynthetics to prevent forest road demage.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.119-127
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• 2017

This paper presents a study of reinforced earth model wall reinforced by geosynthetics subjected to vertical surcharge. 7 types of reinforced earth model wall were constructed in the model box($100cm{\times}140cm{\times}100cm$) to assess the deformation and stress behavior of model walls according to different tensile strength and laying number of reinforcement and surcharge pressures. 3 types of geosynthetics that have different tensile strength were used as reinforcement. The test was carried out by changing the number of reinforcement to 5, 7, 9, and surcharge pressure to 50, 100, 150, 200, 250 kPa. The model test found that the maximum lateral displacements occurred at the 0.7 H (H : Wall height) position from the bottom of the model wall and vertical stress was low in the smaller surcharge pressure and the larger tensile strength of reinforcement.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.232-239
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• 2005

Recently geosynthetics that can be constructed on soft ground have been used for reinforcement and separation in various ways. Through laboratory model tests and numerical analysis, in this study, estimated the suitability of cable elements and appropriate input factors considering loading effect in modeling of geosynthetics. First, in laboratory model tests, geosynthetics were constructed on the clay, and covered with the thickness, 7.5cm of sand mat. And then static and dynamic model tests were performed measuring loading, settlement, ground lateral displacement, and displacements of geosynthetics, but, for cyclic loading, bearing capacity increased linearly with stiff slop because cyclic loading with constant cyclic pressure compacted the ground. Numerical analysis were performed with FLAC 4.0 2D using Mohr-Coulomb and Modified Cam-Clay models, and they compared with the results of model tests. Cable elements of FLAC in modeling geosynthetics couldn't consider the characteristics of geosynthetics that increase shear strength between geosynthetics and clay according to the loading increase. Therefore, in this study, appropriate equation that can consider loading effects in Cable elements was proposed by Case Study.

• Journal of the Korean Geosynthetics Society
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• v.4 no.3
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• pp.21-33
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• 2005

This paper presented a mechanism of the soil structure reinforced by geosynthetics, in which the reinforcing mechanism is treated as the effect arising from the reinforcement process to prevent the dilative deformation of soil under shearing. A full-scale in-situ model test was carried out by introducing the prestress method to enhance the geosynthetic-reinforcement, and the prestress effect through the FEM is also examined. The elasto-plastic model and the initial parameters needed in the FEM are presented. Moreover, the theoretical prediction is compared with the experimental results, which were obtained by a full-scale in-situ model test.

• Journal of the Korean Geosynthetics Society
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• v.2 no.2
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• pp.33-38
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• 2003

Polyester woven geotextiles to be bonded with nonwovens were manufactured for reinforcement and the allowable strength of these were obtained by the results of creep tests. Long-term design strength were calculated in consideration with factors of safety for design and construction and the long-term behaviors of geogrids were compared to those of composite woven geotextiles to examine the reinforcement function. From the experimental results, it was confirmed that these woven composite geotextiles could have the sufficient performance as an alternative geosynthetics instead of geogrids and the further study will be continue to confirm the possibility of woven composite geotextiles as the excellent reinforcing material.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.333-336
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• 2002

Geosynthetics 제품에는 각각의 구조나 물리적 또는 화학적 특성에 기인한 봉합방법이 적용되고 있으며, 특히, 보호/보강용 geosynthetics 제품의 봉합강도는 봉합방법에 크게 영향을 받는다. 일반적으로 봉합부위는 하중전달 시 응력집중현상이 발생되는 부위이며, 보호/보강용 geosynthetics 제품인 부직포 지오텍스타일의 경우 중량이 커질수록 두꺼워져 기존의 봉합용 재봉기를 이용하기 어렵기 때문에 새로운 봉합기술의 연결재를 이용한 봉합에 문제가 발생하게 된다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.21-22
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• 2003

4 types rubber related geosynthetics were manufactured to examine the performance to for applications to the civil and geotechnical fields, especially to the road construction. Reinforcement and water barrier function of these geosynthetics were interpreted as the important properties. Fiber glass mat based and geogrid based geosynthetics showed the excellent mechanical properties as. Also elastomeric bitumen based geosynthetic showed the highest permittivity. From this, it i s thought that this geosynthetic is suitable for water barrier under specific load condition.

• Journal of the Korean Geosynthetics Society
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• v.18 no.1
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• pp.25-37
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• 2019

This study confirms reinforcing effect of geosynthetics in the use of soil at higher water contents as a compaction material on compaction tests, field compaction tests, and numerical analysis. To verify a confined effect, a large mold(area ratio of rammer / mold = 0.19) larger than D compaction mold(area ratio of rammer / mold = 0.33) was performed for compaction. It showed that in the D compaction test, dry density were 0.5~0.6% increases and in the compaction test using the large mold, it were 2.4~3.7% increases at high water contents. It shows that when the area of compacted area is large enough, a confined effect could be arising from the reinforcement of geosynthetics even at high water contents. As a result of analyzing of compaction effects according to 'depth(z/B) from compacted surface' in the field, when not reinforced, the compaction state deteriorated due to the over-compaction and the compaction did not work well. However, when reinforcement of geosynthetics, restraint effect by geosynthetics occurs, it is confirmed that the compaction energy is effectively transferred to the compaction layer and the dry density is increased. Also, through the conceptual model of the behavior of geosynthetic and soil layer, the mechanism in the ground due to reinforcement of geosynthetics is presented and it is verified through finite element analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.12a
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• pp.57-72
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• 1998