• Title/Summary/Keyword: post-tensioned concrete pavement

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Experimental Analysis of Prestressed Approach Slab Behavior (프리스트레스가 도입된 접속슬래브의 실험적 거동 분석)

  • Park, Hee-Beom;Eum, In-Sub;Kim, Seong-Min
    • International Journal of Highway Engineering
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    • v.12 no.4
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    • pp.157-164
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    • 2010
  • This research was conducted to analyze the behavior of Single-PTAS (Single Post-Tensioned Approach Slab) under tensioning and environmental loads by performing field tests when the demonstration Single-PTAS was being constructed. The temperature measurement sensors were installed at different depths, and the displacements in the approach slab under environmental loads and tensioning were measured using displacement transducers. As an experimental result, an abrupt change in the longitudinal displacement due to tensioning was not observed. The daily temperature change in the approach slab was negligible where the depth is over about 35cm. The temperature gradient in the approach slab adjacent to bridge was smaller than that adjacent to pavement. The patterns and magnitudes of vertical displacements were directly related to the temperature gradient at the measuring location. The behavior of Single-PTAS was very similar to that of concrete pavement. Therefore, a new design methodology for approach slabs is needed to include the pavement concept and to overcome drawback of current design procedures based on the simple beam concept.

Load Transfer Test for Re-tensioning Post-Tension Kit for Prestressed Concrete (프리스트레스트 콘크리트 부재용 재긴장 정착구 하중전달시험)

  • Hur, Jae-Hoon;Lho, Byeong-Cheol
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.5
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    • pp.8-14
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    • 2021
  • 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.