An experimental method for evaluating reinforcement corrosion in cracked concrete

This technical note presents an experimental method for evaluating corrosion behavior of steel-reinforcement bars in cracked concrete members. The method utilizes a small (23.5 cm (9.25 in.) deep x 7.6 cm (3 in.) wide x 81.3 cm (32 in.) long) reinforced concrete beam specimen which is intentionally cracked through application of an eccentric posttensioning force. Because the posttensioning is applied using a threaded rod and turn-of-the-nut tightening, the width of the resulting flexural crack can be adjusted to a desired size. After the concrete is cracked, a chloride solution is introduced to accelerate corrosion, and electrochemical measurements of corrosion can be made. Simplicity of the specimen, adjustability of crack size and ability to create flexural cracks are the primary benefits of the method. Details of an ongoing test program are presented to demonstrate the application of the method. Alternative test methods reported in the literature are also briefly reviewed.