Research on the particle characteristics of manufactured sands affecting the flow ability of fresh mortar

Abstract

This paper combined digital image processing (DIP) and discrete element method (DEM) to investigate the relationship between the particle characteristics of manufactured sand and the flow ability of mortar, and clarified the key characteristics parameters of particle shape influencing the flow ability of mortar. A method for batch calculation of shape characteristic parameters (elongation ne, angularity index na and fullness ratio nf) of aggregates based on DIP was proposed. The fluidity tests and corresponding simulations of mortar at different water-cement ratios were carried out respectively, and the results showed that the errors of simulated fluidity (fm) were around 7%. The simulation results demonstrated that the fm decreased with increasing content of large-size aggregates in the mortar. The augment of both ne and na reduced the flowability of mortar. The magnitude of rolling/sliding friction coefficients of aggregates are the important parameters that determine the flowability of mortar.