Análise da substituição parcial do agregado miúdo por resíduo de fibrocimento na produção de argamassa de assentamento

Abstract

The Civil Construction assumes a great importance in the Brazilian economy and is also responsible for high consumption of natural resources. Besides consuming a lot of raw materials taken from nature, the Civil Construction Waste (CCW) represent a huge volume When compared to the Solid Urban Waste (SUW). Thus, the environmental impacts are significant. And it is within this scenario that the present work aims to analyze the rheological and physical- mechanical behavior of mortar produced with treated fiber-cement artifacts waste as a partial substitute for fine aggregate. For this purpose, a comparison is made between the properties of conventional mortar and one with fiber-cement waste in the fresh (consistency) and in the hardened (flexural tensile strength, compressive strength and capillary absorption) states. For the processing of fiber-cement waste, a Los Angeles Abrasion equipment was used after cleaning the material and for the study of the rheological and physical-mechanical behavior the methodologies presented in NM 248 (ABNT, 2003), NBR 16541 (ABNT, 2016), NBR 13276 (ABNT, 2016), NBR 13279 (ABNT, 2005) and NBR 15259 (ABNT, 2005) were applied. The consistency studies indicated the need for the use of plasticizer admixture from 15% of substitution on. The natural fine aggregate and the fine aggregate from fiber-cement waste had their granulometric curves determined and compared. The flexural tensile and compressive strengths increased compared to the reference mixture from 15% of substitution on and the capillarity indexes were lower compared to the reference mixture also from 15% on. Although the results have been satisfactory, the processing time in the Los Angeles Abrasion Equipment and the high consumption of plasticizer admixture make the use of fiber cement waste unsatisfactory.