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Load Transfer Test for Re-tensioning Post-Tension Kit for Prestressed Concrete

프리스트레스트 콘크리트 부재용 재긴장 정착구 하중전달시험

  • 허재훈 (상지대학교 건설시스템공학과) ;
  • 노병철 (상지대학교 건설시스템공학과)
  • Received : 2021.04.08
  • Accepted : 2021.09.02
  • Published : 2021.10.30

Abstract

Post-tensioned prestressed concrete members experience immediate prestress losses as well as time-dependent prestress losses such as creep, dry shrinkage and relaxation. In addition, the stress of the upper and lower parts of the member changes due to the change in dead load due to the replacement of the upper slab and/or pavement. Such changes in fiber stress may affect the safety of the member, and it is necessary to adjust the prestressing force. Therefore, in this study, a screw type of re-tensioning post-tension kit is proposed, and it is verified that the safety against load and the stability against strain are satisfied through the load transfer test specified in EAD160004 and KCI-PS101.

포스트텐션 프리스트레스트 콘크리트 부재는 즉시 손실 이외에도 크리프, 건조수축 및 릴렉세이션과 같은 시간적 손실이 발생한다. 아울러 상부 슬래브 또는 포장 등의 교체 등에 의한 고정하중 변동으로 인하여 부재 상하부의 응력이 변화하게 된다. 이러한 응력의 변화는 부재의 안전성에 영향을 줄 경우가 있으며, 이 경우 프리스트레스 힘의 조절이 필요하다. 따라서 이 연구에서는 나사를 적용한 새로운 유형의 재긴장 포스트텐션 정착구를 제안하고, EAD160004 및 KCI-PS101에 규정된 하중전달시험을 통하여 하중에 대한 안전성과 변형률에 대한 안정성을 만족함을 구명하였다.

Keywords

Acknowledgement

본 연구는 (주)한국PCS와 상지대학교 교내연구비의 지원으로 이루어진것으로 관계자 여러분께진심으로 감사드립니다.

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