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)
  • Received : 2010.11.13
  • Accepted : 2012.02.28
  • Published : 2012.04.10

Abstract

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.

Keywords

References

  1. Corven, J.A. (2001), Mid-Bay Bridge Post-tensioning Evaluation - Final Report, Florida Department of Transportation (FDOT), Corven Engineering Inc., Tallahassee, FL.
  2. FHWA (2004), Post-Tensioning Tendon Installation and Grouting Manual, Federal Highway Administration (FHWA), Washington, DC.
  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
  4. Im, S.B., Hurlebaus, S. and Trejo, D. (2010b), "Inspection of voids in external tendons of post-tensioned bridges", Transport. Res. Record: J. Tran. Res. Board, 2172, 115-122. https://doi.org/10.3141/2172-13
  5. O'Neil, E.F. and Schupack, M. (1997), "Steel post-tensioning tendon behavior - up to 35-year marine exposure", Proceedings of ASCE Structures Congress, 324-328.
  6. Park, R. (1975), "Post-tensioned tendons in prestressed concrete - to grout or not to grout?", New Zealand Eng., 30(11), 315-319.
  7. PCI (1997), Chapter 3: Fabrication and Construction, PCI Bridge Design Manual, Prestressed Concrete Institute, Chicago, IL.
  8. Pearson-Kirk, D. (2003), "The performance of post-tensioned bridge", Role of Concrete Bridges in Sustainable Development - Proceedings of the International Symposium, 129-140.
  9. Pielstick, B. (2002), "Grouting of segmental posttensioned bridges in America", Transport. Res. Record, 1813, 235-241. https://doi.org/10.3141/1813-28
  10. Pillai, R.G. (2009), "Electrochemical characterization and time-variant structural reliability assessment of posttensioned, segmental concrete bridges", Ph.D Dissertation, Texas A&M University, College Station, TX.
  11. Raiss, M. (1995), "Post-tensioned concrete bridges: the UK debate", Concrete Int., 29(2), 23-26.
  12. Schokker, A.J., Breen, J.E., and Kreger, M.E. (2001), "Grouts for bonded post-tensioning in corrosive environments", ACI Mate. J., 98(4), 296-305.
  13. Shoji, N., Noritaka, S., Yasushi, K. and Koichiro, S. (2003), "Development of repair method for poorly grouting of PC structures", Concrete J., 41(11), 31-43. https://doi.org/10.3151/coj1975.41.11_31
  14. Sprinkel, M. and Napier, C.S. (2008), "VDOT experience with grouted tendons in Varina-Enon precast segmental post-tensioned bridge", Virginia Concrete Conference.
  15. Trejo, D., Hueste, M.B., Gardoni, P., Pillai, R., Reinschmidt, K., Im, S.B., Kataria, S., Hurlebaus, S., Gamble, M. and Ngo, T. (2009a), Effect of Voids in Grouted Post-tensioned Concrete Bridge Construction, Vol. 2, Texas Department of Transportation (TxDOT), Austin, TX.
  16. Trejo, D., Im, S.B., Pillai, R., Hueste, M.B., Gardoni, P., Hurlebaus, S. and Gamble, M. (2009b), Effect of Voids in Grouted Post-Tensioned Concrete Bridge Construction: Inspection and Repair Manual for External Tendons in Post-tensioned Bridges, Texas Department of Transportation (TxDOT), Austin, TX.
  17. TxDOT (2004), Critical Evaluation and Condition Assessment of Post-Tensioned Bridges in Texas, Texas Department of Transportation (TxDOT), Austin, TX.
  18. VSL (2002), Grouting of Post - Tensioning Tendons. Report Series 5, VSL International Ltd., Lyssach, Switzerland.
  19. Woodward, R.J. and Miller, E. (1990), "Grouting post-tensioned concrete bridges: the prevention of voids", Highw. Transport., 37(6), 9-17.

Cited by

  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