Transfer Length of the Soil Nail Induced by the Shear Deformation

Min Ku You; Sang Duk Lee

doi:10.7843/kgs.2018.34.6.61

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2018 Vol.34, Issue 6 Preview Page

Research Article

Transfer Length of the Soil Nail Induced by the Shear Deformation 전단변형에 따른 쏘일네일의 전이길이

30 June 2018. pp. 61-73

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Abstract

When the shear deformation occurs on the slope reinforced with soil nail, a passive earth pressure is induced on the ground around the soil nail and the increase of shear deformation causes the earth pressure variation of the ground and the deformation and member force change of the soil nail. In this study, the shear behavior of the soil nail was analyzed experimentally by inducing the shear deformation in the vertical direction of the soil nail using a large-scale direct shear test equipment and it was verified through numerical analysis. The shear test was performed on the bonded length (6D, 8D, 10D and 12D) of the soil nail separated from the shear surface. As a result, it was observed that the continuous increase of the shear deformation caused the damage of the grout and the effect according to the bonded length was analyzed. Through the model test and the numerical analysis, it was confirmed that the transfer length of the soil nail was 0.2～0.22m, which is larger than 0.1m suggested in the previous study, and the shear zone was in the range of 0.6m from the shear surface.

Keywords

Soil nail

Shear behavior

Transfer length

Large-scale direct shear test

쏘일네일 보강지반에 전단변형이 발생하면 쏘일네일 주변지반에는 수동토압이 유발되고, 전단변형의 증가는 주변지반의 토압 변화와 쏘일네일의 변형 및 부재력 변화를 야기한다. 본 연구에서는 대형 직접전단시험기를 이용하여 쏘일네일의 수직방향으로 전단변형을 유발하면서 쏘일네일의 전단거동을 실험적으로 분석하였으며, 수치해석을 통해 검증하였다. 전단면에서 이격된 쏘일네일의 정착부 길이(6D, 8D, 10D, 12D) 변화를 변수로 전단시험을 실시하였다. 연구결과, 전단변형의 지속적인 증가는 그라우트의 손상을 유발함을 확인하였으며, 정착부 길이변화에 따른 영향을 확인하였다. 모형시험과 수치해석을 통해 분석된 쏘일네일의 전이길이는 0.2～0.22m로 기존 연구에서 제시한 0.1m 보다 크게 증가하였으며, 전단영역은 전단면에서 0.6m까지의 범위로 확인되었다.

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Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 34
No :6
Pages :61-73
Received Date : 2018-04-30
Revised Date : 2018-05-28
Accepted Date : 2018-06-04
DOI :https://doi.org/10.7843/kgs.2018.34.6.61

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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