Motive Characteristics and Adhesion-Rebound Mechanism of Single Aggregate Based on Shotcrete

Abstract

The theory of viscoelastic collision mechanics is used to explore the rebound and adhesion mechanisms of single aggregates in shotcrete at the meso-level in this study. Abrasive balls with different radiuses were used, fully considering the characteristics of the aggregates and the sprayed wall, to build multifactor physical models for the shotcrete rebound of the aggregate. The movement trajectories, velocities, and energy dissipations of abrasive balls are analyzed, and the shotcrete-rebound mechanical model of a single aggregate based on wet-mix shotcrete is proposed. The results of the study show that there are obvious differences in the rebound velocity of the aggregate in different collision forms, and the viscoelastic properties of aggregates affect the jet stability of wet-mix shotcrete. According to the quantitative and qualitative analyses, the energy loss during the collision-rebound of the aggregate is inversely proportional to the rebound velocity and proportional to the rebound resistance. The functional relationship between the resistance F and the particle radius R during the rebound and adhesion of aggregate can be expressed as F=CR1/5, where C is a constant.