Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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Evaluation of Pullout Capacity of Anchors by Bonded Length through Model Test

모형시험을 통한 정착길이별 앵커의 인발저항력 평가

  • Han, Jae-Myoung (Dept. of Geotechnical Tunnel, Yongma Engineering) ;
  • Kim, Gyu-Hyeong (Dept. of Civil Engineering, Daejin University) ;
  • Woo, Jong-Tae (Dept. of Construction and Environmental Design, Kyungbok University) ;
  • Lee, Kang-Il (Dept. of Civil Engineering, Daejin University)
  • Received : 2017.08.06
  • Accepted : 2017.09.14
  • Published : 2017.09.30
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Abstract

A series of pullout tests to compression type anchors is conducted. The test is carried out on a couple of steel cables installed in sandy soil with 60% of relative density. The test is performed with 6 different bonded lengths, which are 1, 2, 3, 4, 5, 6 times longer than the initial bonded length (Lc =30 mm). A numerical analysis with the same condition as the test is also performed to compare each other. Finally, those results are compared with theoretical result by Oosterbaan and Gifford (1972). The result shows that the ultimate pullout capacity appears to increase with an increase of bonded length, and that the results of test, numerical analysis and theoretical approach have a good agreement in the ultimate pullout capacity at failure.

본 연구는 역학적으로 우수한 압축형 앵커를 모형토조 내에 2개의 강연선을 설치하고 상대밀도가 60%인 모래지반을 형성한 후 인발시험을 실시하였다. 인발시험은 정착길이(Lc=30mm)의 1, 2, 3, 4, 5, 6배로 무차원화 하여 6가지 경우로 나누어 실시하였으며, 그리고 앵커체는 2개를 동시(Pt-1, Pt-2)에 인장하는 경우에 대하여 실시하였다. 또한 모형시험과 동일 조건으로 유한 요소 수치해석을 실시하고, 두 경우의 변위에 따른 인발력을 비교평가 한 후 Oosterbaan and Gifford(1972)의 이론식과 비교하였다. 그 결과 앵커의 정착길이가 증가함에 따라 극한 인발력이 증가하는 양상을 보이고 있으며, 모형시험과, 수치해석 이론식 모두 파괴시점의 극한인발력은 서로 근접함을 확인할 수 있었다.

Keywords

References

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