文档介绍：外文文献:
Materials and Structures
© RILEM 2010
-010-9700-y
Original Article
Impact of crack width on bond: confined and unconfined rebar
David W. Law1 , Denglei Tang2, Thomas K. C. Molyneaux3 and a Gravina3
(1) 
School of the Built Environment, Heriot Watt University, Edinburgh, EH14 4AS, UK
(2) 
VicRoads, Melbourne, VIC, Australia
(3) 
School of Civil, Environmental and Chemical Engineering, RMIT University, Melbourne, VIC, 3000, Australia
David W. Law
Email: .******@
Received: 14 January 2010  Accepted: 14 December 2010  Published online: 23 December 2010
Abstract
This paper reports the results of a research paring the effect of surface crack width and degree of corrosion on the bond strength of confined and unconfined deformed 12 and 16 mm mild steel reinforcing bars. The corrosion was induced by chloride contamination of the concrete and an applied DC current. The principal parameters investigated were confinement of the reinforcement, the cover depth, bar diameter, degree of corrosion and the surface crack width. The results indicated that potential relationship between the crack width and the bond strength. The results also showed an increase in bond strength at the point where initial surface cracking was observed for bars with confining stirrups. No such increase was observed with unconfined specimens.
Keywords:  bond ;corrosion ; rebar ; cover ; crack width ; concrete
1   Introduction
The corrosion of steel reinforcement is a major cause of the deterioration of reinforced concrete structures throughout the world. In uncorroded structures the bond between the steel reinforcement and the concrete ensures that reinforced concrete acts in posite manner. However, when corrosion of the steel occurs posite performance is adversely affected. This is due to the formation of corrosion products on the steel surface, which affect the bond between the steel and the concrete.
The deterioration of reinforced concrete is characte