Journal of the Society of Disaster Information (한국재난정보학회 논문집)

The Korean Society of Disaster Information (한국재난정보학회)
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Stability Evaluation of Anchors Using Lift-off Field Test

리프트오프 현장시험을 이용한 앵커의 안정성 평가

  • Choi, Tae Sic (Department of Civil Engineering, Daejin University) ;
  • Yun, Jung Mann (Department of Civil Engineering, Shin Ansan University) ;
  • Kim, Yong Seong (Department of Regional Infrastructure Engineering, Kangwon National University) ;
  • You, Seung Kyong (Department of Civil Engineering, Myongji College) ;
  • Lee, Kang Il (Department of Civil Engineering, Daejin University)
  • Received : 2021.01.05
  • Accepted : 2021.02.23
  • Published : 2021.03.31
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Abstract

Purpose: This study examines the safety management of anchors that have already been constructed and evaluates the results of lift-off tests conducted at the site. The purpose of the project is to study countermeasures if necessary. Method: Compare the residual load gained after the lift-off test at 36 points behind the site with the preemptive load, allowable load, and design load. We also analyze stability through this and evaluate the stability of anchors. Results and Conclusion: The residual tension at 26 points remained stable. However, the residual load at 10 points was analyzed to be greater than the designed load and less than the allowable load, and it was evaluated as an instability that could cause fracture problems. Therefore, anchors with unstable conditions at 10 points should be monitored and monitored through periodic measurements and quality tests, and the anchor should be observed at the surrounding points as well as the relevant points to maintain stability.

연구목적: 본 연구는 기 시공된 앵커의 안전관리에 대하여 고찰을 실시하고 이를 통해 현장에서 실시한 리프트오프 시험결과를 평가한다. 또한 필요 시 대책공법에 대하여 연구하는 것을 목적으로 한다. 연구방법: 현장의 가시설 배면 36개의 지점에 리프트오프 시험을 수행한 후 얻어진 잔존긴장력에 대해 강연선항복하중, 허용긴장력 및 설계긴장력과 비교한다. 또한 이를 통해 안정성을 분석하고 앵커의 안정상태를 평가한다. 연구결과 및 결론: 시험결과 26개 지점의 잔존긴장력은 안정상태에 있었다. 그러나 10개 지점에서 잔존긴장력이 설계긴장력 보다 크고 허용긴장력 보다 작은 것으로 분석되었고 파단문제가 발생할 수 있는 불안정상태인 것으로 평가되었다. 따라서 10개 지점에서 나타난 불안정상태의 앵커는 주기적인 계측과 품질시험을 통한 관리 및 관찰을 수행해야 하며 해당 지점뿐 아니라 주변 지점에 대해서도 주기적인 관찰을 실시하여 안정상태를 유지시켜야 한다.

Keywords

References

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