Experimental Study on External Anchorage Technique for Strengthening of the Existing Bridges

Abstract:

Anchoring the external prestressing to the bridge end block is one of the key issues for strengthening of existing concrete bridges. This paper presents an innovative technique to fix steel brackets to the sides of the end block by two transverse pretensioned through-rods and three expansion bolts in both friction and shear pattern. In order to validate the technique, two steel reinforced concrete specimens (J1 and J2) fixed with experimental steel brackets are prepared and an experiment investigation has been carried out. Two sudden failures have been observed. The failure patterns of expansion bolts in J1 are pullout failure and shear failure, and two transverse pretensioned through-rods have large yield deformation. The failure patterns of expansion bolts in J2 are similar, but the failure patterns of two transverse pretensioned through-rods are shear fracture. The relationship of force and slip is linear but with two different slope when the load less than 2000kN in both J1 and J2.

• Periodical: Applied Mechanics and Materials (Volumes 351-352)
• Pages: 1499-1502
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.351-352.1499
• Online since: August 2013
• Authors: Yan Jun Hu, Yan Liang Du
• Keywords: Anchorage, Bridge, External Prestressing, Transverse Pretensioned Through-Rods

References

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[2] S. Saibabu1S: Practice Periodical on Structural Design and Construction14 (2) (2009)90-98.

[3] Screw-thread steel bars for the prestressing of concrete (GB/T 20065-2006) (in Chinese).