The Crack Development Mechanism of Prestressed Girder Influenced by Different Bond between Prestressed Tendons and Concrete

Abstract:

The paper deals with formation and development of cracks up to the failure of two span post-tensioned concrete girder. It is focused on influence of different bond between prestressing units and surrounding grout. Monitored and analysed phenomena affected by different bond are as follows: crack initiation, crack spacing and crack width of the prestressed girder. Sources of analysis are results from experimental program focused on influence of oil based corrosion protection agents on bond of prestressing units. Two span post-tensioned girders were subjected to the loading in laboratory till the bending failure has occurred. Girders were in two cases prestressed with bonded tendons. Other two girders were post-tensioned with unbonded tendons and two girders with tendons with decreased bond, due to corrosion protection coatings. Girders have demonstrated different behaviour by loading regarding to the bond level of prestressing units. Experimental results are faced with the results of the theoretical calculation of crack width according to European standards.

• Periodical: Key Engineering Materials (Volume 691)
• Pages: 309-320
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.691.309
• Online since: May 2016
• Authors: Viktor Borzovič*, Ján Laco, Miroslav Pecník, Peter Pažma
• Keywords: Bond of Prestressing Units, Crack Width, Experimental Research, Post-Tensioned Structures

References

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