Bond-slip behavior of self-consolidating rubberized concrete

A sustainable solution was found for the use of waste material such as used tires by partially replacing the natural aggregate in the concrete with recycled rubber particles. This resulted in improved ductility, but at the expense of reduced strength and stiffness. To further investigate the behavior of rubberized concrete, this paper investigates the bond-slip behavior of reinforcement in self-consolidating rubberized concrete. A total of 27 cubic specimens with reinforcement bars and embedded confinement were constructed. Two parameters affecting the bond-slip behavior were investigated: the reinforcement bar diameter (O12, O16, O20 mm), the content of rubber particles in the self-consolidating concrete (0%, 10%, 15%), and silica fume (0%, 5%). From the experimental results, it can be concluded that both a higher rubber content and a larger reinforcement diameter have a negative effect on the bond coefficient, reducing it by up to 28.87% and 18.78%, respectively, while the bond strength decreases by 33% for a rubber replacement of 15%. In the case of rubberized concrete, a more ductile behavior is observed due to the rubber content. Based on the obtained results, a parametric analysis was performed and an analytical prediction model was proposed.