Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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Seam Tensile Strength of Geotextile Mat and Stress Increment Analysis

지오텍스타일 봉합 인장강도와 지반의 응력증가분 해석

  • Chae, Yu-Mi (Department of Civil Engineering, Dongshin University) ;
  • Kim, Jae-Hong (Department of Civil Engineering, Dongshin University)
  • Received : 2018.10.30
  • Accepted : 2018.11.14
  • Published : 2018.12.30
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Abstract

In the west coast, south coast, and river basin, the use of geotextile mats has been increasing to improve the soft ground for making industrial facilities space and farmland. As an initial step to improve the vast and soft ground, the geotextile mats are laid and bonded to increase the bearing capacity of the wide ground for supporting construction equipment. Seam strength of geotextile mats exert a force only about 50% of the tensile strength of the fabric, which causes problems such as uplift and sinking in the soft ground. In this study, various types of geosynthetic matting techniques were investigated and the tensile strength of each method was compared and analyzed. Numerical analysis shows that stress increment in the ground due to the overburden load decreases when the seam strength of the geosynthetics mats is increased. When the seam strength was increased to 60, 70 and 80%, the bearing capacity of ground by geotextile mat was increased.

서해안과 남해안 그리고, 하천유역에는 연약지반을 개량하여 산업시설 공간과 농경지 확보를 위해 토목섬유매트 활용이 많아지고 있다. 광대한 연약한 지반을 개량하기 위한 초기단계로 장비 진입을 위해 토목섬유매트를 포설하고 접합하여 넓은 지반의 지지력을 증대시킨다. 토목섬유매트 봉합강도는 원단 인장강도의 50% 정도만 힘을 발휘하고 있어 장비주행성에 융기와 침하 등 지지력 저하의 문제들이 발생한다. 본 연구는 여러 가지 토목섬유매트 봉합기술들을 분석하고 각 방법들의 인장강도를 비교분석하였다. 또한 토목섬유매트의 봉합강도를 증가시켰을 때, 상재하중에 의한 지반내의 응력증가분이 감소하는 경향을 수치해석으로 확인하였다. 봉합강도를 60, 70, 80%으로 향상시켰을 때 토목섬유에 의한 지반의 지지력 증가를 확인할 수 있었다.

Keywords

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Fig. 1. Case of uplift and settlement in soft ground

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Fig. 2. Scheme of Yamanouchi method to calculate bearing capacity with geotextile tensile strength (Yamanouchi, 1985)

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Fig. 3. Scheme of Meyerhof method to consider inhomogeneous layer in soft soil (Meyerhof, 1974)

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Fig. 4. Boundary condition for stress increment in finite element analysis

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Fig. 5. Vertical strain by overburden load

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Fig. 6. Enlarged figure of Fig. 5 for stress

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Fig. 7. Stress increment by overburden load (without geotextile mat)

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Fig. 9. Stress increment by overburden load (inertia moment of geotextile mat = 20,000 m4)

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Fig. 8. Stress increment by overburden load (inertia moment of geotextile mat = 10,000 m4)

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Fig. 10. Stress increment by overburden load (inertia moment of geotextile mat = 40,000 m4)

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Fig. 11. Variation of stress increment by overburden load

Table 1. Punching shear factors with the soil friction angle (Meyerhof, 1974)

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Table 2. Geotextile Fabric Comparison (Gerard, 1994)

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Table 3. Physical parameters of materials

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References

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