Mechanical and Corrosion Investigations of Bond Behavior in Reinforced Concrete with Varying Parameters

The bond strength between reinforcing steel bars and cement concrete plays significant role in the structural performance for civil infrastructure. This work presents the bond performance of steel and concrete as interfacial shear strength, with the inclusion of effects of specimen diameter on embedment length, different aggregate grading and corrosion. The experimental procedure for proposed study includes a series of pullout tests on reinforced concrete cylindrical specimens with embedded steel bar. Cylindrical concrete specimens with varying specimen diameters with respect to different embedment lengths, changing the aggregate grading pattern, i.e., well and gap graded were casted and said effects on bond strength were evaluated through a pullout test. The corrosion effect is also studied through an accelerated corrosion process. The test results revealed that the diameter of the specimen and the embedment length substantially impact the bond strength between reinforcing bars and concrete. Due to the increasing surface area and mechanical interaction between the bar and the surrounding concrete, the bond strength increased as the diameter decreased. The bond performance of well-graded aggregates was effective compared to gap-graded aggregates. Moreover, the study found that as the number of corrosion days increased, the bond strength of corroded reinforcing bars considerably decreased. The results contribute essential insights to the field of reinforced concrete structures and can aid engineers and researchers in designing durable and reliable infrastructure systems.