Influence of the physical characteristics of sand and the crushed filler content on the properties of self-leveling mortars

Abstract

The properties of self-leveling mortars (SLMs) in the fresh and hardened state are strongly affected by their formulation. In this study, the influence of three different quartz sands (different physical characteristics) was investigated in SLMs, as well as the replacement of these sands by crushed basalt filler. The tests performed were: spreading, density in the hardened state, absorption by immersion, flexural strength, compressive strength, dynamic modulus of elasticity, water capillary absorption, and drying shrinkage. The results obtained show that the particle size distribution (PSD) of sand influenced most of the properties. The shape and texture of the sand grains did not seem to have much influence on the properties of SLMs when the PSD was different. The powdery (fine) material content of sand seemed to affect most notably properties in the fresh state and shrinkage. The increase in the content of sand replacement by filler decreased the workability of SLMs, however, it may improve the initial flexural and compressive strengths and reduce the drying shrinkage.

Keywords:
self-leveling mortar; quartz sand; crushed filler; mechanical strength; drying shrinkage