Friction Influence between Particles in the Behavior of Flow of Lime-Rendering Mortars

Abstract

The behavior and properties of rendering mortars, in the fresh state, are influenced primarily by particle grading, amount of water employed, and the shape and surface texture of particles. Production processes and application of rendering mortars demand an appropriate adjustment in their materials so that the plasticity and consistency need to be optimized allowing an appropriate execution of rendering. The friction between particles of sand is decisive in the rheological behavior of mortars. In this context, the present study evaluates the mortar flow behavior focusing on the influence of microfine content and grading of sands on friction angle of mortars. For experimental development, mortars that differ according to binder/aggregate ratios and aggregate grading distributions were used, in addition to using sands with different microfine contents. The mortar consistencies were established based on the cone penetration test. The mortars were tested to determine the internal friction angle using the direct shear test. The yield stress was obtained from the Vane test. The results indicate a relationship between the microfine content and the internal friction angle of the mortars, identifying a strong influences of friction under the behavior of flow of the rendering mortars.