An Investigation of Transfer Length In Pretensioned Concrete Using Photoelasticity

摘要

style="text-align: left;">One of the methods most commonly used to provide the required amount of prestress in prestressed concrete structures is the pretensioning method. In this method tendons are prestressed before the  concrete is placed by temporarily anchoring them against the stressing beds. After the concrete ha:s been placed  and reaches a desired strength, the tendons are released to Transfer their prestress force to the concrete beam. This transfer of stress implies the existence of bond between the tendons and the concrete. >References style="text-align: left;">1. Base, G. D. target="_blank" title=""Some Tests on Effect of Time on Transmission Length in Pretensioned Concrete"" href="http://dx.doi.org/10.1680/macr.1957.9.26.73 ">"Some Tests on Effect of Time on Transmission Length in Pretensioned Concrete", Magazine of Concrete Research, Vol. 9. No. 26. pp 73- 82. April 1957. style="text-align: left;">2. Base, G. D. "An Investigation of Transmission Length in Pretensioned Concrete", Report of Cement and Concrete Association. Report No. 5. August 1958. style="text-align: left;">3. Douglas D. J., and Trahair, N. S., target="_blank" title=""An Examination of the Stresses in the  Anchorage Zone of Post Tensioned Prestressed Concrete Beams"" href=" http://dx.doi.org/10.1680/macr.1960.12.34.9 ">"An Examination of the Stresses in the  Anchorage Zone of Post Tensioned Prestressed Concrete Beams". Magazine of Concrete Research. Vol. 12,March 1960. style="text-align: left;">4. Eastwood, W., "Resistance to Slip of Wires in Pretensioned Prestressed Concrete Girders", Review of Civil Engineering  and Public Works. P. 74. 1954. style="text-align: left;">5. Evans, R. H., and Ribinson, G. W., "Bond Stresses in Prestressed Concrete  from X-ray Photographs". Proceedings of Institution of Civil Engineers. Part 1. Vol. 4. No. 2. March 1955. style="text-align: left;">6. Evans, R. H., "Research and Development in Prestressing", Journal of the  Institution of Civil Engineers, Vol. 35. No. 4. P. 31. style="text-align: left;">7. Filon, L. N. G., "A Manual of Photoelasticity for Engineers", Cambridge University Press. London. 1936. style="text-align: left;">8. Frocht, M., "Photoelasticity", Vol. 1-2, John Wiley and Sons, Inc. New York, N.Y. 1957. style="text-align: left;">9. Guyon, Y., "Prestressed Concrete",  Vol. 1-2. Contractors Record Ltd. London. 1960. style="text-align: left;">10. Hognestad, E., and Janney, J. R., target="_blank" title=""The Ultimate Strength of Pretensioned Prestressed Concrete Failing in Bond"" href="http://dx.doi.org/10.1680/macr.1954.6.16.11 ">"The Ultimate Strength of Pretensioned Prestressed Concrete Failing in Bond",  Magazine of Concrete Research. June 1954. style="text-align: left;">11. Janney, J. R., target="_blank" title=""Nature of Bond in Pretensioned Prestressed Concrete"." href="http://dx.doi.org/10.14359/11790 ">"Nature of Bond in Pretensioned Prestressed Concrete". Journal American Concrete Institute. Vol. 50. P. 717 August 1954. style="text-align: left;">12. Jessop, H. T., and Harris, F. C., "Photoelasticity," Cleaver Hume Press Ltd.  London. 1949. style="text-align: left;">13. Lee, H. L., target="_blank" title=""An Introduction to Experimental Stress Analysis,"" href="http://dx.doi.org/10.1016/0016-0032(50)90713-7 ">"An Introduction to Experimental Stress Analysis," John Wiley and Sons, Inc., New York. 1959. style="text-align: left;">14. Lin, T. Y., "Design of Prestressed Concrete Structures," John Wiley and Sons, Inc. New York, New York, 1959. style="text-align: left;">15. Sethunarayanan, Rm., target="_blank" title=""UltimateStrength of Pretensioned I Beams in Combined Bending and Shear."" href="http://dx.doi.org/10.1680/macr.1960.12.35.83 ">"Ulti