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.

Influence of bottom ash and red mud additions on self-leveling underlayment properties

“…All mortars produced showed high mechanical (flexural and compressive) strength, in accordance with the values defined in ASTM C1708 [10], at all ages tested. It is noteworthy that the compressive strength values obtained at 1 day of curing were higher compared to the values reported at 1 day of curing of PCbased SLUs [41], and close compared to the values reported at 7 days of curing of PC-based SLUs [42]. At the initial curing age (1d), the replacement of LF by BA and RM promoted an increase in the compressive strength values, mainly for higher addition contents.…”

“…At 28 days of curing, the highest drying shrinkage values shown in Fig. 8a (0.3_ RM) were close to the lowest values obtained in SLUs based on CAC/C$/PC system with high PC contents [2], and 10 times smaller compared to those obtained with selfleveling PC-based underlayments [41]. Mortars with 0.2 replacement of LF by BA and RM showed lower mass loss at the initial curing age (3d, Fig.…”

Influência da composição de agregado miúdo de rio e proveniente do processo de britagem em argamassas autoadensáveis

“…Para argamassas de assentamento/revestimento, WESTERHOLMet al [11] afirmam que, em termos de tensão de escoamento e viscosidade, as argamassas produzidas com agregados britados apresentem maiores valores, visto que o efeito da forma da partícula é preponderante, além da presença de finos.No entanto, SCOLARO e ROCHA [12] verificaram que a forma e a textura dos grãos da areia não afetam significativamente as propriedades das argamassas autoadensáveis, considerando agregados com granulometrias diferentes, e que a influência do fino presente na areia é mais significativa nas propriedades do estado fresco e na retração.…”