Comparison of the fracture process of the rubberized concrete and plain concrete under bending load

Acoustic emission (AE) technique is employed to investigate the damage process of the notched plain concrete and rubberized concrete specimens under 3-point bending load.AE signals in the fracture process of notched specimens are illustrated by analyzing the distribution of amplitude and hit rate of AE signals.AE signals in the rubberized concrete have lower activity and amplitude than in the plain concrete.By AE location analysis,it is found that the high energy events mainly are distributed near the notch tip.According to AE energy,the fracture process zone (FPZ) is determined.By comparing the FPZ of both concretes,it is found that the incorporation of rubber particles in concrete can greatly alleviate the damage process of concrete specimens and the damage zone in the rubberized concrete is much smaller than in the plain concrete.The moment tensor is also used to analyze the type of cracks and it is found that tensile cracks dominate the early period of loading,while shear cracks become dominant with propagation of cracks in late load period.