Acoustic emission characteristics of fatigue failure process of self-compacting rubberized concrete pavement slabs

Abstract

ABSTRACT To explore the fatigue characteristics of self-compacting rubberized concrete (SCRC) pavement, notched slabs with a 10% rubber content were fabricated. Monotonic and fatigue tests were carried out, including incremental amplitude tests controlled by crack mouth opening displacement (CMOD), load, and alternative constant and incremental amplitude loads. Meanwhile, the fracture process was dynamically monitored with acoustic emission (AE), and the failure characteristics were analyzed based on AE parameters. Under monotonic loads, cracks mainly develop along with the interface between aggregates or rubber particles and cement. The cumulative ring counts and damage evolution show a three-stage distribution. The b-value fluctuates dramatically initially and less in the middle and later stages under monotonic tests. Under fatigue loads, brittle fractures are significant and fatigue life increases. Only one inflection point appears in the cumulative ringing counts curve and damage evolution curve, the critical damage is lower. The fluctuation range of the b-value are higher. The cumulative ringing counts, AE signal intensity, damage parameter based on AE energy, and b-value can dynamically reflect the crack growth and damage evolution of SCRC slabs. The fracture mode analysis based on AF-RA manifests cracks are mainly tensile, and the fracture mode is the type I.