Flowability of multi-sized mixed particles based on shotcrete aggregates

In the shotcrete construction process, the calculation and prediction of the flowability of multi-sized mixed aggregates is essential. Based on shotcrete aggregates, the bulk density, tapped density, and flowability evaluation parameters such as Hausner ratio (HR) and angle of repose (AoR) were measured for multi-sized mixed spherical and non-spherical particles. Mono-sized spherical and non-spherical particles were also used as a control. The results show that the particle bulk density, tapped density, and flowability for a mono-sized can be described as a function of particle size and Archimedes number (Ar). In addition, the particle size distribution of shotcrete aggregates is quantitatively described using the gradation equation, obtaining the functional relationship between the multi-sized mixed particles parameters and the Splog, which is defined based on span function and gradation equation. Compared to HR, AoR enables a more detailed flowability classification of shotcrete aggregates.