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Bending characteristics of Prestressed High Strength Concrete (PHC) spun pile measured using distributed optical fibre strain sensor

  • 투고 : 2020.04.12
  • 심사 : 2021.09.18
  • 발행 : 2022.02.25

초록

Pre-stressed concrete circular spun piles are widely used in various infrastructure projects around the world and offer an economical deep foundation system with consistent and superior quality compared to cast in-situ and other concrete piles. Conventional methods for measuring the lateral response of piles have been limited to conventional instrumentation, such as electrical based gauges and pressure transducers. The problem with existing technology is that the sensors are not able to assist in recording the lateral stiffness changes of the pile which varies along the length depending on the distribution of the flexural moments and appearance of tensile cracks. This paper describes a full-scale bending test of a 1-m diameter spun pile of 30 m long and instrumented using advanced fibre optic distributed sensor, known as Brillouin Optical Time Domain Analysis (BOTDA). Optical fibre sensors were embedded inside the concrete during the manufacturing stage and attached on the concrete surface in order to measure the pile's full-length flexural behaviour under the prescribed serviceability and ultimate limit state. The relationship between moments-deflections and bending moments-curvatures are examined with respect to the lateral forces. Tensile cracks were measured and compared with the peak strains observed from BOTDA data which corroborated very well. By analysing the moment-curvature response of the pile, the structure can be represented by two bending stiffness parameters, namely the pre-yield (EI) and post-yield (EIcr), where the cracks reduce the stiffness property by 89%. The pile deflection profile can be attained from optical fibre data through closed-form solutions, which generally matched with the displacements recorded by Linear Voltage Displacement Transducers (LVDTs).

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참고문헌

  1. Abendroth, R.E., Greimann, L.F. and LaViolett, M.D. (2007), "An Integral Abutment Bridge with Precast Concrete Piles", IHRB Project TR-438, Iowa Highway Research Board & Iowa Department of Transportation, USA.
  2. Abu-Farsakh, M.Y., Haque, M.N. and Tsai, C. (2017), "A full-scale field study for performance evaluation of axially loaded large-diameter cylinder piles with pipe piles and PSC piles", Acta Geotech., 12(4), 753-772. https://doi.org/10.1007/s11440-016-0498-9
  3. Aso, T., Miura, F., Inoue, T. and Yamamoto, M. (2004), "Non-linear bending characteristics of PHC piles under varying axial load", Proceedings of the 13th World Conference on Earthquake Engineering, WCEE, in CD-ROM, 1-9.
  4. Avent, R.R. and Mukai, D.J. (1998), "Investigation of Cracks in Cylindrical Spun-Cast Concrete Piles in a Marine Environment", Louisiana Transportation Research Center, LA-98/320.
  5. Bao, Y., Tang, F., Chen, Y., Meng, W., Huang, Y. and Chen, G. (2016), "Concrete pavement monitoring with PPP-BOTDA distributed strain and crack sensors", Smart Struct. Syst., Int. J., 18(3), 405-423. http://doi.org/10.12989/sss.2016.18.3.405
  6. Chow, C.C. and Tan, Y.C. (2010), "Performance of jack-in pile foundation in weathered granite", Proceedings of the 17th SEA Geotechnical Conference, Taipei, Taiwan, pp. 1-4.
  7. Feng, X., Wu, W., Li, X., Zhang, X. and Zhou, J. (2015), "Experimental investigations on detecting lateral buckling for subsea pipelines with distributed fiber optic sensors", Smart Struct. Syst., Int. J., 15(2), 245-258. http://doi.org/10.12989/sss.2015.15.2.245
  8. Goldfeld, Y. and Klar, A. (2013), "Damage identification in reinforced concrete beams using spatially distributed strain measurements", J. Struct. Eng., 139(12), 04013013. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000795
  9. Hartman, J.J., Castelli, R.J. and Malhotra, S. (2007), "Design and Installation of Concrete Cylinder Piles", In: Contemporary Issues in Deep Foundations, (in W. Camp, R. Castelli, D.F. Laefer and S. Paikowsky eds.), American Society of Civil Engineers.
  10. Hong, W.P., Kim, J.H. and Hong, S. (2019), "Role of piles in mitigating the movement of pipes in soft grounds during embankment loading", Mar. Georesources Geotechnol., 37(9), 1019-1031. https://doi.org/10.1080/1064119X.2018.1523973
  11. Huang, X., Yang, M., Feng, L., Gu, H., Su, H., Cui, X. and Cao, W. (2017), "Crack detection study for hydraulic concrete using PPP-BOTDA", Smart Struct. Syst., Int. J., 20(1), 75-83. https://doi.org/10.12989/sss.2017.20.1.075
  12. Joen, P.H. and Park, R. (1990), "Flexural strength and ductility analysis of spirally reinforced prestressed concrete piles", PCI J., 35(4), 64-83. https://doi.org/10.15554/pcij.07011990.54.83
  13. Joint ACI-ASCE Committee 423 (2016), ACI PRC-423.10-16 Guide to Estimating Prestress Losses, American Concrete Institute, Farmington Hills, MI, USA.
  14. Kesavan, K., Ravisankar, K., Parivallal, S. and Sreeshylam, P. (2005), "Applications of fiber optic sensors for structural health monitoring", Smart Struct. Syst., Int. J., 1(4), 355-368. https://doi.org/10.12989/sss.2005.1.4.355
  15. Kim, S.T., Park, Y., Park, S.Y., Cho, K. and Cho, J.R. (2015), "A sensor-type PC strand with an embedded FBG sensor for monitoring prestress forces", Sensors, 15(1), 1060-1070. https://doi.org/10.3390/s150101060
  16. Liew, S.S., Lee, S.T. and Koo, K.S. (2010), "Failure Investigation of Piled Reinforcement Soil Wall & Excessive Movements of Piled Embankment at Soft Ground, Malaysia", Proceedings of the 17th Southeast Asian Geotechnical Conference, Taipei, Taiwan, 3P-191.
  17. Liu, H.B., Zhang, Q. and Zhang, B.H. (2017), "Structural health monitoring of a newly built high-piled wharf in a harbor with fiber Bragg grating sensor technology: design and deployment", Smart Struct. Syst., Int. J., 20(2), 163-173. https://doi.org/10.12989/sss.2017.20.2.163
  18. Lu, Y., Shi, B., Wei, G.Q., Chen, S.E. and Zhang, D. (2012), "Application of a distributed optical fiber sensing technique in monitoring the stress of precast piles", Smart Mater. Struct., 21(11), 115011. https://doi.org/10.1088/0964-1726/21/11/115011
  19. Mohamad, H., Soga, K. and Amatya, B. (2014), "Thermal strain sensing of concrete piles using Brillouin optical time domain reflectometry", Geotech. Test. J., 37(2), ASTM, 333-346. https://doi.org/10.1520/GTJ20120176
  20. Mohamad, H., Tee, B.P., Ang, K.A. and Chong, M.F. (2016), "Characterizing anomalies in distributed strain measurements of cast-in-situ bored piles", Jurnal Teknologi, 78(8-5), 75-82. https://doi.org/10.11113/jt.v78.9626
  21. Mohamad, H., Tee, B.P., Chong, M.F. and Ang, K.A. (2017), "Investigation of shaft friction mechanisms of bored piles through distributed optical fibre strain sensing", Proceedings of the 19th International Conference on Soil Mechanics and Geotechnical Engineering, ISMGE, pp. 2829-2832.
  22. Mohamad, H., Tee, B.P., Chong, M.F., Ang, K.A., Rashid, A.S.A. and Abdullah, R.A. (2019), "Instrumented laterally loaded pile test using distributed fibre optic sensor", Geotech. Eng., 50(2), 36-42.
  23. MS1314: Part 2 (2004), Precast Concrete Piles: Part 2: Method for Determination of Bending Strength of Precast Concrete Piles (Bend Test), Malaysian Standard, Department of Standards Malaysia.
  24. Ni, P., Mangalathu, S., Mei, G. and Zhao, Y. (2017), "Compressive and flexural behaviour of reinforced concrete permeable piles", Eng. Struct., 147, 316-327. https://doi.org/10.1016/j.engstruct.2017.06.007
  25. Pelecanos, L., Soga, K., Elshafie, M.Z.E.B., Battista, N., Kechavarzi, C., Gue, C.Y., Ouyang, Y. and Seo, H.J. (2018), "Distributed fiber optic sensing of axially loaded bored piles", J. Geotech. Geoenviron. Eng., 144(3), 04017122. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001843
  26. Rausche, F. and Webster, S. (2007), "Behavior of cylinder piles during pile installation", In: Contemporary Issues in Deep Foundations, (in W. Camp, R. Castelli, D.F. Laefer and S. Paikowsky eds.), American Society of Civil Engineers.
  27. Vitharana, N. (1997), "Rational prediction of lateral behaviour of concrete piles incorporating pile (concrete) non-linearity", Proceedings of the 14th International Conference on Soil Mechanics and Foundation Engineering, Recent developments in foundation techniques, pp. 915-920.
  28. Volgyi, I., Farkas, G. and Nehme, S.G. (2010), "Concrete strength tendency in the wall of cylindrical spun-cast concrete elements", Period Polytech.-Civil, 54(1), 23-30. http://dx.doi.org/10.3311/pp.ci.2010-1.03
  29. Whiting, W.A. (1952), "Reinforced concrete pipe", U.S. Patent, No. 2,602,469, 8 Jul. 1952.
  30. Zou, L., Bao, X., Yang, S., Chen, L. and Ravet, F. (2006), "Effect of Brillouin slow light on distributed Brillouin fiber sensors", Opt. Lett., 31(18), 2698-2700. http://dx.doi.org/10.1364/OL.31.002698