Mechanical and Vibration Properties of Self-compacting Rubberized Concrete Beams with Silica Fume Enhancement

Incorporating rubber into concrete aligns with sustainable development goals, making the mechanical evaluation of structural rubber concrete beams crucial for design purposes and assessing the seismic vulnerability of rubberized concrete structures. This study focuses on the experimental evaluation of the mechanical behavior of self-compacting concrete beams containing rubber particles and assesses the effects of silica fume to counterbalance the reduced strength of rubberized concrete. The experiments determined the load-deformation curve, load capacity, crack patterns and propagation, frequency, and damping ratio of the beams. The results indicate that while the compressive and tensile strengths of the beams can decrease by up to 70% due to the incorporation of rubber particles, the addition of silica fume significantly enhances these strengths by up to 60% and 66%, respectively. Although rubber particles reduce the ultimate load-bearing capacity of the beams, they help limit crack depth and increase the number of cracks along the beam's length. As a result, the inclusion of rubber particles improves the inherent damping ratio and displacement ductility of the beams. The frequency of the beams decreases by up to 10%, while their damping ratio increases by as much as 2.7 times with the incorporation of rubber particles.