Structural Engineering and Mechanics

  • 제42권1호
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  • Pages.25-38
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  • 2012
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

Determination of the repair grout volume to fill voids in external post-tensioned tendons

  • Im, Seok Been (Bridge/Structure Part, Civil ENG Center, Samsung C&T) ;
  • Hurlebaus, Stefan (Zachry Department of Civil Engineering, Texas A&M University)
  • 투고 : 2010.11.13
  • 심사 : 2012.02.28
  • 발행 : 2012.04.10
⟨ 이전 논문 다음 논문 ⟩

초록

Recently, investigated failures of external post-tensioned (PT) tendons have called attention to the corrosion of strands in PT bridges, and the prevention of ongoing corrosion is required to secure their structural integrity. Since voids inside ducts can be a source for the ingress of water or deleterious chemicals, the vacuum grouting (VG) method and a volumeter for estimating amount of repair grouts were employed to fill voided ducts. However, the VG method is expensive and time-consuming for infield application because it requires an air-tight condition of entire ducts. Thus, latest research assessed three different repair grouting methods, and the pressure vacuum grouting (PVG) method was recommended in the field because it showed good filling capability in voided ducts and did not require an air-tight condition. Thus, a new method is required to estimate the volume of repair grouts because the PVG method is not applied in air-tight ducts. This research assesses the relationship between voided areas on ducts identified with soundings and required grout volume for repair using experimental results. The results show that the proposed equations and assumptions for estimating repair grout volume provide a sufficient amount of repair grouts for filling voided ducts.

키워드

참고문헌

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  3. Im, S.B., Hurlebaus, S. and Trejo, D. (2010a), "Effective repair grouting methods and materials for filling voids in external post-tensioned tendons", Transport. Res. Record: J. Tran. Res. Board, 2172, 3-10. https://doi.org/10.3141/2172-01
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피인용 문헌

  1. Electromagnetic characterization of grouting materials of bridge post tensioned ducts for NDT using capacitive probe vol.60, 2013, https://doi.org/10.1016/j.ndteint.2013.07.010
  2. Filtration-induced pressure evolution in permeation grouting vol.75, pp.5, 2012, https://doi.org/10.12989/sem.2020.75.5.571