Physico-mechanical characterization of composite cementitious mortars modified by resin containing antifoam

Abstract

Nowadays, polymer-modified mortars (PMM) are generally used in the field of building as finishing materials. In general, The properties of the fresh and hardened PMC are affected by several factors that tend to interact each other: the nature of materials used as latex, cement and aggregates; the mix proportions (W/C, polymer/cement ratio, etc.); air content; type and amount of surfactants and anti-foaming; and curing methods. This present experimental work aims to study the influence of the rate of partial substitution of cement by resin containing anti-foaming on the properties of composite mortars in the fresh and hardened state particularly workability, tensile and compressive strengths at different times (3, 7 and 28 days) and module of static elasticity at 28 days. For that purpose, seven mortar combinations were developed from the various substitution percentages (0 to 15% by step of 2.5%). The treatment of the obtained results reveals that this partial replacement of the cement by resin improves, clearly, the workability of mortars and decreases the report W/C at the same time. Besides, the incorporation of resin affects significantly the mechanical strengths, and consequently, the addition by substitution of the polymer-latex improves, slightly, the mechanical behavior in tensile where the rates of increase range from 2.20% to 8.54% for replacement percentages of 2.5% and 15%, respectively. Furthermore, the compressive strengths of cement - resin composite mortars are lower compared to the reference mortar made with the cement Portland (CEM I). The notable decrease in compressive strength of polymer–modified mortars can be justified by the reduction of cementitious part, in hybrid materials, which is an indispensable and responsible part of improving compressive strength.