Abstract:

The bond strength between steel bars and rubberized concrete is crucial for the engineering application of rubberized concrete. To investigate the bonding properties under various loading rates, center pull-out tests were conducted under a range of loading rates (0.01 mm/s to 1 mm/s). The impacts of loading rate, rubber replacement ratio, and steel bar diameter on the bonding performance and the failure mode were examined. Results indicate that steel bar diameter significantly influences the failure mode of the pull-out specimens: specimens with 18 mm diameter bars exhibited split failures, while those with 14 mm diameter bars experienced pull-out failures. Additionally, loading rate markedly affects key parameters in the bond stress-slip curve. Based on theoretical analysis, a new model for the bond-slip relationship between steel bars and rubberized concrete under varying loading rates was proposed. Model evaluation demonstrates that predictions from this model align well with experimental results, which manifests the model’s applicability to predicting the bond stress-slip relationship between steel bars and rubberized concrete across different loading rates.

Key words: rubberized concrete, steel bar, pull-out test, loading rate, bonding performance