Computers and Concrete

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Experimental, numerical and analytical studies on a novel external prestressing technique for concrete structural components

  • Lakshmanan, N. (SERC, CSIR, CSIR Campus) ;
  • Saibabu, S. (SERC, CSIR, CSIR Campus) ;
  • Murthy, A. Rama Chandra (SERC, CSIR, CSIR Campus) ;
  • Ganapathi, S. Chitra (SERC, CSIR, CSIR Campus) ;
  • Jayaraman, R. (SERC, CSIR, CSIR Campus) ;
  • Senthil, R. (Structural Engineering Department, Anna University)
  • Received : 2008.02.20
  • Accepted : 2009.02.04
  • Published : 2009.02.25
⟨ Previous Next ⟩

Abstract

This paper presents the details of a novel external prestressing technique for strengthening of concrete members. In the proposed technique, transfer of external force is in shear mode on the end block thus creating a complex stress distribution and the required transverse prestressing force is lesser compared to conventional techniques. Steel brackets are provided on either side of the end block for transferring external prestressing force and these are connected to the anchor blocks by expansion type anchor bolts. In order to validate the technique, an experimental investigation has been carried out on post-tensioned end blocks. Performance of the end blocks have been studied for design, cracking and ultimate loads. Slip and slope of steel bracket have been recorded at various stages during the experiment. Finite element analysis has been carried out by simulating the test conditions and the responses have been compared. From the analysis, it has been observed that the computed slope and slip of the steel bracket are in good agreement with the corresponding experimental observations. A simplified analytical model has been proposed to compute load-deformation of the loaded steel bracket with respect to the end block. Yield and ultimate loads have been arrived at based on force/moment equilibrium equations at critical sections. Deformation analysis has been carried out based on the assumption that the ratio of axial deformation to vertical deformation of anchor bolt would follow the same ratio at the corresponding forces such as yield and ultimate. It is observed that the computed forces, slip and slopes are in good agreement with the corresponding experimental observations.

Keywords

References

  1. Angel, C. Aparicio, Gonazalo Ramos and Juan R. Casas (2002). Testing of externally prestressed concrete beams. Eng. Struct. 24(1), 73-84. https://doi.org/10.1016/S0141-0296(01)00062-1
  2. Angel, C. Aparicio, Gonzalo Ramos, Juan R. Casas (2000). Externally prestressed high strength concrete viaduct, ASCE J. Bridge Eng., 5(4), 337-343. https://doi.org/10.1061/(ASCE)1084-0702(2000)5:4(337)
  3. ANSYS 6.0 Theory and Reference Manual, 2002.
  4. Ayaho Miyamoto Katsuji Tei, Hideaki Nakamura and John W. Bull (2000). Behavior of prestressed beam strengthened with external tendons. ASCE J. Struct. Eng. 126(9), 1033-1044. https://doi.org/10.1061/(ASCE)0733-9445(2000)126:9(1033)
  5. Bahaari, M.R. and Sherbourne, A.N. (2000). Behaviour of eight-bolt large capacity end plate connections. Comput. Struct. 77(3), 315-325. https://doi.org/10.1016/S0045-7949(99)00218-7
  6. Choy, S.C., Wong, Y.L., Chan, S.L. (2002). Shear strength of prestressed concrete encased steel beams with bonded tendons. Third International conference on Advances in Steel Structures, Hong Kong, China, 543-549.
  7. Christoph Czaderski and Masoud Motavalli (2007). 40-Year-old full-scale concrete bridge girder strengthened with prestressed CFRP plates anchored using gradient method. Composites: Part. B. Eng. 38(7-8), 878-886. https://doi.org/10.1016/j.compositesb.2006.11.003
  8. Fanning, P.J., Tucker, M. and Broderick, B.M. (2000). Non-linear finite element analysis of semi-rigid bolted end-plate connections, In: Proc Fifth International Conference on Computational Structures Technology, Civ. Compress, Edinburgh, UK, 397-403.
  9. Jung, J.W., Abolmaahi, Ali and Choi, Y. (2006). Finite element analysis of tapered steel and Fiber-Reinforced Plastic Bridge Camera Poles. ASCE J. Bridge Eng. 611-617.
  10. Kim, J., Yoon, J.-C. and Kang, B.-S. (2007). Finite element analysis and modeling of structure with bolted joints. Appl. Math. Model. 31, 895-911. https://doi.org/10.1016/j.apm.2006.03.020
  11. M.A. McNeff P.E. (1999). Calculating service moment capacity of anchor bolted connections. ASCE Practice periodical on Structural Design and Construction, 4CD: 33-35.
  12. Shiming Chen (2005). Experimental study of prestressed steel-concrete composite beams with external tendons for negative moments. J. Constr. Steel Res. 61(12), 1613-1630. https://doi.org/10.1016/j.jcsr.2005.05.005
  13. Tie-jiong, Lou and Yi-qiang Xiang (2006). Finite element modeling of concrete beams prestressed with external tendons. Eng. Struct. 28(14), 1919-1926. https://doi.org/10.1016/j.engstruct.2006.03.020
  14. Zhongguo (John) Ma, Mohsen A Saleh, Maher K Tadros (1999). Optimized post-tensioning anchorage in prestressed concrete I-beams. PCI J., 56-73.

Cited by

  1. Management and Maintenance Scheduling of Infrastructural Facilities: Road Map vol.26, pp.6, 2012, https://doi.org/10.1061/(ASCE)CF.1943-5509.0000283
  2. Development of Embedded EM Sensors for Estimating Tensile Forces of PSC Girder Bridges vol.17, pp.9, 2017, https://doi.org/10.3390/s17091989
  3. FBG Sensors Encapsulated into 7-Wire Steel Strand for Tension Monitoring of a Prestressing Tendon vol.15, pp.6, 2012, https://doi.org/10.1260/1369-4332.15.6.907
  4. Calculation of Incremental Force of External Steel in Simply Supported Externally Prestressed Beams vol.163-167, pp.1662-8985, 2010, https://doi.org/10.4028/www.scientific.net/AMR.163-167.1719
  5. Monitoring of tension force and load transfer of ground anchor by using optical FBG sensors embedded tendon vol.7, pp.4, 2009, https://doi.org/10.12989/sss.2011.7.4.303
  6. Friction element for non-linear analysis of friction effect in externally prestressed beams vol.173, pp.3, 2020, https://doi.org/10.1680/jstbu.18.00040