Avaliação de casos de retração em argamassas de revestimento devido ao uso de "cal líquida"

Abstract

This article evaluates the measure of mortar retraction with plasticiser additive, well-known as “liquid-lime”, based on 1:1:6 (cement:lime:sand) very used in coatings at the city of Uberlândia-MG. Because the retraction is a phenomenon originated by the mix of dry materials with water and occurs with the mortar in fresh and hardened states, this article’s aim is to compare two segments in lab, with a) a minute after modelling, until 24 hours; b) 48 hours after modelling, until 28 days. In fresh state, the properties were evaluated as texture, plasticity and workability, and in the hardened state, the proof-bodies utilized were modelling for different ages (24 hours, 7 days, and 28 days), which are prismatic proof-bodies of 4x4x16cm for bending traction trial and cylinders of 5x10cm for compression trials, and also plates of 50x50cm with thickness of 1,5cm (representing a rate of the thickness used in the region) for adherence trials, and permeability evaluation through the pipe's method.