The effect of repairs on the corrosion of reinforcing bars in concrete was studied on concrete slabs containing a rectangular recess to facilitate the development of corrosion macrocells. These slabs were initially exposed to ponding and drying in the form of wet-dry cycles with each cycle consisting of 4 days of ponding and 10 days of drying in order to allow the steel in the recessed area to corrode preferentially. They were subsequently repaired and re-exposed to wet-dry cyling to examine the effect of the repair. Since the repaired slabs containded a repaired portion and an unrepaired portion, increased galvanic action was possible. After a number of wet-dry cycles following the repair, the bars in the slabs were exposed to observe the condition of the steel. The steel bars exhibited a variety of conditions ranging from clean to severely corroded. While it is difficult to assess the exact contribution of the repair to the subsequent corrosion which resulted, it is clear that the repaired area behaved in a different manner than the remaining bars. In some cases, a visible barrier had developed around the steel portion that was repaired. This served to protect that portion of the bar from further deterioration.

Subject
Steel structures, Concrete repair, Materials, Photography, Wiring, Slabs, Repair, Steel, Rust, Corrosion protection, Half cell potential, Drying, Concrete
© 1991 Association for Materials Protection and Performance (AMPP). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without the prior written permission of AMPP. Positions and opinions advanced in this work are those of the author(s) and not necessarily those of AMPP. Responsibility for the content of the work lies solely with the author(s).
1991
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.